https://www.coastalwiki.org/w/index.php?title=Fluid_mud&feed=atom&action=history
Fluid mud - Revision history
2024-03-29T11:36:34Z
Revision history for this page on the wiki
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https://www.coastalwiki.org/w/index.php?title=Fluid_mud&diff=80619&oldid=prev
Dronkers J at 17:30, 12 January 2024
2024-01-12T17:30:48Z
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 17:30, 12 January 2024</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l48" >Line 48:</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Buoyancy suppresses turbulent exchange between layers of different density,</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Buoyancy suppresses turbulent exchange between layers of different density,</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>stimulating the formation of a lutocline - a <del class="diffchange diffchange-inline">usually sharp interface </del>between <del class="diffchange diffchange-inline">layers </del>with <del class="diffchange diffchange-inline">different </del>suspended sediment concentrations, see Fig. 2.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>stimulating the formation of a lutocline - a <ins class="diffchange diffchange-inline">thin transition layer </ins>between <ins class="diffchange diffchange-inline">an upper and a lower layer </ins>with <ins class="diffchange diffchange-inline">low and high </ins>suspended sediment concentrations <ins class="diffchange diffchange-inline">respectively</ins>, see Fig. 2.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The density difference between the layers is thereby further increased as an auto-enhancing process.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The density difference between the layers is thereby further increased as an auto-enhancing process.</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>According to Winterwerp<ref>Winterwerp, J.C. 2001. Stratification effects by cohesive and non-cohesive sediments. J.Geophys.Res. 106: 22559-22574</ref>, the density increase may finally exceed the sediment carrying capacity of the lower layer, leading to the collapse of this layer and the formation of a mud bed.  </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>According to Winterwerp<ref>Winterwerp, J.C. 2001. Stratification effects by cohesive and non-cohesive sediments. J.Geophys.Res. 106: 22559-22574</ref>, the density increase may finally exceed the sediment carrying capacity of the lower layer, leading to the collapse of this layer and the formation of a mud bed. <ins class="diffchange diffchange-inline">Observations in a turbid shallow macrotidal estuary show that unstable shear-induced wave motions on the lutocline (so-called [https://en.wikipedia.org/wiki/Kelvin%E2%80%93Helmholtz_instability Kelvin-Helmholz instability]) can oppose stratification by enhancing vertical mixing<ref>Tu, J., Fan, D., Lian, Q., Liu, Z., Liu, W., Kaminski, A. and Smyth, W. 2020. Acoustic observations of Kelvin‐Helmholtz billows on an estuarine lutocline. Journal of Geophysical Research: Oceans 125, e2019JC015383</ref>.  </ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>For further details on mud transport, mud bed formation and destruction see [[Dynamics of mud transport]].</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>For further details on mud transport, mud bed formation and destruction see [[Dynamics of mud transport]].</div></td></tr>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Sediment deposition and erosion processes]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Sediment deposition and erosion processes]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Flocculation cohesive sediments]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Flocculation cohesive sediments]]</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">:[[Estuarine turbidity maximum]] </ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Coastal and marine sediments]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Coastal and marine sediments]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Mud]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Mud]]</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">:[[Estuarine turbidity maximum]] </del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Characteristics of muddy coasts]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Characteristics of muddy coasts]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Coastal mud belt]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Coastal mud belt]]</div></td></tr>
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Dronkers J
https://www.coastalwiki.org/w/index.php?title=Fluid_mud&diff=80615&oldid=prev
Dronkers J at 09:08, 5 January 2024
2024-01-05T09:08:44Z
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 09:08, 5 January 2024</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l6" >Line 6:</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Fluid mud composition==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Fluid mud composition==</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Fluid mud is composed mainly of water and clay- and silt-sized particles. The solid content is dominated by clay minerals with a smaller proportion of silt size minerals such as micas (see [[Coastal and marine sediments]]). The mineral composition is location dependent. The fraction organic matter in marine mud is generally very small, especially in comparison with fresh water environments. The water fraction is very high, more than 90% up to 99.5%. At densities above 1150-1200 kg/m3 (gelling point) the fluidity disappears.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Fluid mud is composed mainly of water and clay- and silt-sized particles. The solid content is dominated by clay minerals with a smaller proportion of silt size minerals such as micas (see [[Coastal and marine sediments]]). The mineral composition is location dependent<ins class="diffchange diffchange-inline">. Cohesiveness is due to electrochemical interparticle bonds and EPS, extracellular polymeric substances exuded by organisms</ins>. The fraction <ins class="diffchange diffchange-inline">of </ins>organic matter in marine mud is generally very small, especially in comparison with fresh water environments. The water fraction is very high, more than 90% up to 99.5%. At densities above 1150-1200 kg/m3 (gelling point) the fluidity disappears.  </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Formation fluid mud layer==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Formation fluid mud layer==</div></td></tr>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Fluid mud can easily slide down a sloping bottom. A slope of about 1% is sufficient. But sliding down an even gentler slope is also possible. This is the case if sufficient external energy is supplied to maintain the mud in colloidal suspension. This could be surface wave energy absorbed in the fluid mud layer, as described above. Fluid mud flows that are maintained in this way are called wave-supported turbidity flows. They can occur during outflow of wave-dominated river deltas into the sea. At tide-dominated deltas, gravity mud flows onto the shelf can occur that remain suspended by tidal energy<ref name=M07/>.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Fluid mud can easily slide down a sloping bottom. A slope of about 1% is sufficient. But sliding down an even gentler slope is also possible. This is the case if sufficient external energy is supplied to maintain the mud in colloidal suspension. This could be surface wave energy absorbed in the fluid mud layer, as described above. Fluid mud flows that are maintained in this way are called wave-supported turbidity flows. They can occur during outflow of wave-dominated river deltas into the sea. At tide-dominated deltas, gravity mud flows onto the shelf can occur that remain suspended by tidal energy<ref name=M07/>.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>With insufficient slope or lack of external energy supply, the fluid mud layer collapses; the mud layer consolidates and becomes part of the soil substrate. Sedimentation is a slow process with a time scale approximately proportional to the square of the layer thickness. Mud gravity flows that feed by taking up sediment from the seafloor are called autosuspended turbidity currents. The density of these mud flows then increases and so does their speed. This type of mud flows can convey mud from shallower to deeper estuarine regions and cause silting up of artificially deepened navigation channels and harbors.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>With insufficient slope or lack of external energy supply, the fluid mud layer collapses; the mud layer consolidates and becomes part of the soil substrate. Sedimentation is a slow process with a time scale approximately proportional to the square of the layer thickness. Mud gravity flows that feed by taking up sediment from the seafloor are called autosuspended turbidity currents. The density of these mud flows then increases and so does their speed. This type of mud flows can convey mud from shallower to deeper estuarine regions and cause silting up of artificially deepened navigation channels and harbors<ins class="diffchange diffchange-inline"><ref name=M07/></ins>.</div></td></tr>
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Dronkers J
https://www.coastalwiki.org/w/index.php?title=Fluid_mud&diff=80614&oldid=prev
Dronkers J at 11:15, 4 January 2024
2024-01-04T11:15:30Z
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 11:15, 4 January 2024</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l3" >Line 3:</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>| definition = Fluid mud is a high-concentration colloidal suspension of fine cohesive sediment particles (< 63 µm with a high percentage of clay particles < 2 µm). }}</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>| definition = Fluid mud is a high-concentration colloidal suspension of fine cohesive sediment particles (< 63 µm with a high percentage of clay particles < 2 µm). }}</div></td></tr>
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<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">==Fluid mud composition==</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">Fluid mud is composed mainly of water and clay- and silt-sized particles. The solid content is dominated by clay minerals with a smaller proportion of silt size minerals such as micas (see [[Coastal and marine sediments]]). The mineral composition is location dependent. The fraction organic matter in marine mud is generally very small, especially in comparison with fresh water environments. The water fraction is very high, more than 90% up to 99.5%. At densities above 1150-1200 kg/m3 (gelling point) the fluidity disappears.</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Formation fluid mud layer==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Formation fluid mud layer==</div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l11" >Line 11:</td>
<td colspan="2" class="diff-lineno">Line 15:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The concentration of fine cohesive sediments in suspension can become very high <del class="diffchange diffchange-inline">close </del>to the seabed. <del class="diffchange diffchange-inline">Processes </del>that contribute to the formation of fluid mud <del class="diffchange diffchange-inline">are</del><ref>McAnally, W.H., Friedrichs, C., Hamilton, D., Hayter, E., Shrestha, P., Rodriguez, H., Sheremet, A. and Teeter, A. 2007. Management of Fluid Mud in Estuaries, Bays, and Lakes. I: Present State of Understanding on Character and Behavior. J. Hydr. Eng. 133: 9-22</ref></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The concentration of fine cohesive sediments in suspension can become very high <ins class="diffchange diffchange-inline">due to </ins></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">#Convergence </del>of <del class="diffchange diffchange-inline">residual fine </del>sediment <del class="diffchange diffchange-inline">transport related to [[Tidal asymmetry </del>and <del class="diffchange diffchange-inline">tidal basin morphodynamics|tidal asymmetry]] and [[estuarine circulation]]. These processes are a major cause of the formation of a turbidity maximum in estuaries (see [[Estuarine turbidity maximum]]). </del></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">*Erosion of (partially) consolidated mud deposits by the combined action of strong waves and currents (storm, springtide conditions).</ins></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">#Stirring of partially consolidated mud deposits subject </del>to <del class="diffchange diffchange-inline">wave-induced pressure variations</del>. <del class="diffchange diffchange-inline">Once formed, the </del>fluid mud layer <del class="diffchange diffchange-inline">is maintained by absorbing part of the wave energy. As a consequence, wave action </del>can be <del class="diffchange diffchange-inline">strongly damped by absorption of wave energy in </del>the <del class="diffchange diffchange-inline">fluid mud layer. The strong wave damping observed at muddy coasts (for example the coasts of Guiana and Surinam, see [[Coastal mud belt]]) is caused by the presence of extensive fluid mud banks</del><ref><del class="diffchange diffchange-inline">Traykovski</del>, <del class="diffchange diffchange-inline">P</del>., <del class="diffchange diffchange-inline">Trowbridge</del>, J. <del class="diffchange diffchange-inline">and Kineke</del>, G. <del class="diffchange diffchange-inline">(2015) Mechanisms of surface wave energy dissipation over a high-concentration sediment suspension</del>. <del class="diffchange diffchange-inline">J</del>. <del class="diffchange diffchange-inline">Geophys</del>. <del class="diffchange diffchange-inline">Res</del>. <del class="diffchange diffchange-inline">Oceans 120</del>: <del class="diffchange diffchange-inline">1638–1681</del></ref>.  </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">*Convergence of residual fine sediment transport related to [[Tidal asymmetry and tidal basin morphodynamics|tidal asymmetry]] and [[estuarine circulation]]. These processes are a major cause of the formation of a turbidity maximum in estuaries (see [[Estuarine turbidity maximum]]).</ins></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">#Settling of mudflocs into the near-bottom suspended layer, see [[Flocculation cohesive sediments]].</del></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">Through these processes fine sediments become trapped in a colloidal suspension, called fluid mud.</del></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Settling of fine cohesive sediments is mainly due to floc forming processes, see [[Flocculation cohesive sediments]]. A fluid mud layer is formed when flocs of fine cohesive particles settle </ins>to the seabed <ins class="diffchange diffchange-inline">in sufficiently high concentration. This occurs under quiet hydrodynamic conditions (small waves and currents, e.g., neap tide, slack water)</ins>. <ins class="diffchange diffchange-inline"> </ins></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">This occurs, for example, in periods around neap tide and near the seawater intrusion limit in turbid estuaries.</del></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Stirring of unconsolidated mud deposits by wave-induced pressure variations is another process </ins>that <ins class="diffchange diffchange-inline">can </ins>contribute to the formation of fluid mud<ref <ins class="diffchange diffchange-inline">name=M07</ins>>McAnally, W.H., Friedrichs, C., Hamilton, D., Hayter, E., Shrestha, P., Rodriguez, H., Sheremet, A. and Teeter, A. 2007. Management of Fluid Mud in Estuaries, Bays, and Lakes. I: Present State of Understanding on Character and Behavior. J. Hydr. Eng. 133: 9-22</ref><ins class="diffchange diffchange-inline">. The high stresses needed in case </ins>of <ins class="diffchange diffchange-inline">advanced consolidation will more likely lead to </ins>sediment <ins class="diffchange diffchange-inline">erosion </ins>and <ins class="diffchange diffchange-inline">suspension rather than </ins>to <ins class="diffchange diffchange-inline">fluidization</ins>. <ins class="diffchange diffchange-inline">A </ins>fluid mud layer can be <ins class="diffchange diffchange-inline">formed when </ins>the <ins class="diffchange diffchange-inline">suspended sediment settles</ins><ref><ins class="diffchange diffchange-inline">Winterwerp</ins>, <ins class="diffchange diffchange-inline">J.C</ins>., <ins class="diffchange diffchange-inline">de Boer</ins>, <ins class="diffchange diffchange-inline">G.</ins>J.<ins class="diffchange diffchange-inline">, Greeuw</ins>, G. <ins class="diffchange diffchange-inline">and van Maren, D</ins>.<ins class="diffchange diffchange-inline">S</ins>. <ins class="diffchange diffchange-inline">2012</ins>. <ins class="diffchange diffchange-inline">Mud-induced wave damping and wave-induced liquefaction</ins>. <ins class="diffchange diffchange-inline">Coastal Engineering 64</ins>: <ins class="diffchange diffchange-inline">102–112</ins></ref>.</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>When mudflocs settle, the suspended sediment concentration near the bottom increases. A dense suspension close to the seabed is formed in which further settling is impeded. There are several theories describing this so-called hindered settling regime<ref>Winterwerp, J.C. 2002. On the flocculation and settling velocity of estuarine mud. Cont. Shelf Res. 22: 1339-1360</ref><ref>Dankers, P.J.T. and Winterwerp, J.C. 2007. Hindered settling of mud flocs: Theory and validation. Continental Shelf Res. 27: 1893-1907</ref>.  </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>When mudflocs settle, the suspended sediment concentration near the bottom increases. A dense suspension close to the seabed is formed in which further settling is impeded <ins class="diffchange diffchange-inline">(Fig. 1)</ins>. There are several theories describing this so-called hindered settling regime<ref>Winterwerp, J.C. 2002. On the flocculation and settling velocity of estuarine mud. Cont. Shelf Res. 22: 1339-1360</ref><ref>Dankers, P.J.T. and Winterwerp, J.C. 2007. Hindered settling of mud flocs: Theory and validation. Continental Shelf Res. 27: 1893-1907</ref>.  </div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>When the flocs fill almost all the space, an interconnected matrix of particle bonds is formed in the dense suspension. Sediment settling then becomes impossible. The sediment concentration at which the space is completely filled is called the gelling concentration <math>c_{gel}</math>. The gelling concentration depends on the nature of the flocs. In some situations a value of 40 g/l is found, but generally the value is higher; <math> c_{gel} \approx</math> 100 g/l.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>When the flocs fill almost all the space, an interconnected matrix of particle bonds is formed in the dense suspension. Sediment settling then becomes impossible. The sediment concentration <ins class="diffchange diffchange-inline"><math>c</math> </ins>at which the space is completely filled is called the gelling concentration <math>c_{gel}</math>. The gelling concentration depends on the nature of the flocs. In some situations a value of 40 g/l is found, but generally the value is higher; <math> c_{gel} \approx</math> 100<ins class="diffchange diffchange-inline">-200 </ins>g/l.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[File:Luto.jpg|thumb|left|450px|Fig. 2. Schematic representation of suspended sediment layers in a turbid estuary.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[File:Luto.jpg|thumb|left|450px|Fig. 2. Schematic representation of suspended sediment layers in a turbid estuary.</div></td></tr>
<tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l42" >Line 42:</td>
<td colspan="2" class="diff-lineno">Line 48:</td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Buoyancy suppresses turbulent exchange between layers of different density,</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Buoyancy suppresses turbulent exchange between layers of different density,</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>stimulating the formation of a lutocline - a sharp interface between layers with different suspended sediment concentrations, see Fig. 2.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>stimulating the formation of a lutocline - a <ins class="diffchange diffchange-inline">usually </ins>sharp interface between layers with different suspended sediment concentrations, see Fig. 2.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The density difference between the layers is thereby further increased as an auto-enhancing process.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The density difference between the layers is thereby further increased as an auto-enhancing process.</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Winterwerp<ref>Winterwerp, J.C. 2001. Stratification effects by cohesive and non-cohesive sediments. J.Geophys.Res. 106: 22559-22574</ref> <del class="diffchange diffchange-inline">argues that </del>the density increase may finally exceed the sediment carrying capacity of the lower layer, leading to the collapse of this layer and the formation of a mud bed.  </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">According to </ins>Winterwerp<ref>Winterwerp, J.C. 2001. Stratification effects by cohesive and non-cohesive sediments. J.Geophys.Res. 106: 22559-22574</ref><ins class="diffchange diffchange-inline">, </ins>the density increase may finally exceed the sediment carrying capacity of the lower layer, leading to the collapse of this layer and the formation of a mud bed.  </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>For further details on mud transport, mud bed formation and destruction see [[Dynamics of mud transport]].</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>For further details on mud transport, mud bed formation and destruction see [[Dynamics of mud transport]].</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;"></del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Hydrodynamics of fluid mud==</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>==Hydrodynamics of fluid mud==</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">As long as the concentration is below the gel point, fluid mud can flow as a viscous near-bed layer, entrained by the flow or by pressure gradients of the overlying water mass. In estuaries, fluid mud layers can be entrained by near-bottom tidal currents over considerable distances without being dispersed over the whole water column<ref>Kirby, R. and Parker, W.R. 1983. Distribution and behaviour of fine sediment in the Severn Estuary and Inner Bristol Channel. U.K.Can.J.Fish.Aquat.Sci. 40 (suppl.): 83-95</ref>. Flow along the bed generates the turbulence needed to prevent the fluid mud from settling.</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">As long as the concentration is below the gel point, fluid mud can flow as a viscous near-bed layer, entrained by the flow or by pressure gradients of the overlying water mass. Fluid mud layers can be entrained by near-bottom currents over considerable distances without being dispersed over the whole water column<ref>Kirby, R. and Parker, W.R. 1983. Distribution and behaviour of fine sediment in the Severn Estuary and Inner Bristol Channel. U.K.Can.J.Fish.Aquat.Sci. 40 (suppl.): 83-95</ref>.</del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;"></del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">If the seabed is sloping, the fluid mud slides down as a turbidity current under the influence of gravity. In shallow water, fluid mud absorbs wave energy.</del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;"></del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">If near-bottom currents are absent or very weak, the fluid mud layer consolidates and becomes part of the bed substrate. The consolidation process can take a long time, and is approximately proportional to the square of the layer thickness.</del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[Image:FluidMudLoireEstuary.jpg|thumb|400px|right|Figure 3: Fluid mud in the Loire estuary during neap tide and low fluvial discharge; km 0 corresponds to the estuarine mouth. Source: Christine Bertier (2011)<ref name=B> Bertier, C. 2011. Dynamique et suivi du bouchon vaseux dans l’estuaire de la Loire. Séminaire Technique sur le transport sédimentaire: Principes et expériences sur le bassin Ligrien, Vierzon 24 Novembre 2011</ref>. ]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>[[Image:FluidMudLoireEstuary.jpg|thumb|400px|right|Figure 3: Fluid mud in the Loire estuary during neap tide and low fluvial discharge; km 0 corresponds to the estuarine mouth. Source: Christine Bertier (2011)<ref name=B> Bertier, C. 2011. Dynamique et suivi du bouchon vaseux dans l’estuaire de la Loire. Séminaire Technique sur le transport sédimentaire: Principes et expériences sur le bassin Ligrien, Vierzon 24 Novembre 2011</ref>. ]]</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>A seabed covered with fluid mud offers almost no resistance to the flow in the overlying layer.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>A seabed covered with fluid mud offers almost no resistance to the flow in the overlying layer.</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Prandle<ref>Prandle, D. 2003. Relationships between tidal dynamics and bathymetry in strongly convergent estuaries. J.Phys.Ocean. 33: 2738-2750</ref> related the friction coefficient to the mud content of the sediment bed in many UK estuaries;  </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Prandle<ref>Prandle, D. 2003. Relationships between tidal dynamics and bathymetry in strongly convergent estuaries. J.Phys.Ocean. 33: 2738-2750</ref> related the friction coefficient to the mud content of the sediment bed in many UK estuaries; he found evidence for a strong decrease of the friction coefficient with increasing mud fraction.</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>he found evidence for a strong decrease of the friction coefficient with increasing mud fraction.</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The reduction in flow resistance is mainly due to the suppression of turbulence at the <ins class="diffchange diffchange-inline">lutocline</ins><ref>Winterwerp, J.C., Manning, A.J., Martens, C., De Mulder, T. and Vanlede J. 2006. A heuristic formula for turbulence-induced flocculation of cohesive sediment. Estuarine, Coastal and Shelf Science 68: 195-207</ref>. The [[Bed roughness and friction factors in estuaries|friction factor]] <math>c_D</math> can be reduced by a factor 10 or even more.</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The reduction in flow resistance is mainly due to the suppression of turbulence at the <del class="diffchange diffchange-inline">lutoclines</del><ref>Winterwerp, J.C., Manning, A.J., Martens, C., De Mulder, T. and Vanlede J. 2006. A heuristic formula for turbulence-induced flocculation of cohesive sediment. Estuarine, Coastal and Shelf Science 68: 195-207</ref>. The [[Bed roughness and friction factors in estuaries|friction factor]] <math>c_D</math> can be reduced by a factor 10 or even more.</div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Fluid mud layers are frequently observed at harbour entrances and in artificially deepened navigation channels<ref>Parker, G., Lanfredi, N.W. and Swift, D.J.P. 1982. Seafloor response to flow in a southern hemisphere sand ridge field: Argentine inner shelf. Sed.Geol.33: 195-216</ref><ref>De Jonge, V.N., Schuttelaars, H.M., Van Beusekom, J.E.E., Talke S.A. and De Swart, H.E. 2014. The influence of channel deepening on estuarine turbidity levels and dynamics, as exemplified by the Ems estuary. Estuarine, Coastal and Shelf Science 139: 46-59</ref>, see [[Siltation in harbors and fairways]]. Fluid mud layers in estuaries often form during neap tides in the [[Slack water|high-water and low-water slack]] zones where saline and fresh water converge and where fine sediments are trapped, see Fig. 3 and [[Estuarine turbidity maximum]].   </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Fluid mud layers are frequently observed at harbour entrances and in artificially deepened navigation channels<ref>Parker, G., Lanfredi, N.W. and Swift, D.J.P. 1982. Seafloor response to flow in a southern hemisphere sand ridge field: Argentine inner shelf. Sed.Geol.33: 195-216</ref><ref>De Jonge, V.N., Schuttelaars, H.M., Van Beusekom, J.E.E., Talke S.A. and De Swart, H.E. 2014. The influence of channel deepening on estuarine turbidity levels and dynamics, as exemplified by the Ems estuary. Estuarine, Coastal and Shelf Science 139: 46-59</ref>, see [[Siltation in harbors and fairways]]. Fluid mud layers in estuaries often form during neap tides in the [[Slack water|high-water and low-water slack]] zones where saline and fresh water converge and where fine sediments are trapped, see Fig. 3 and [[Estuarine turbidity maximum]].   </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div><br clear=all></div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div><br clear=all></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">==Wave damping==</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">Once formed, the fluid mud layer can be maintained by absorbing part of the energy of surface waves. As a consequence, incident waves can be strongly damped by absorption of wave energy in the fluid mud layer. The strong wave damping observed at muddy coasts (for example the coasts of Louisiana, Guiana and Surinam, see [[Coastal mud belt]]) is caused by the presence of extensive mud banks<ref name=M07/>. Wave damping is due to energy transfer from the surface wave motion to forced wave motion (same period and wavelength) in the fluid mud layer, where the energy is dissipated by viscous diffusion of fluid momentum. According to an idealized analytical model by Gade (1985<ref>Gade, H.G. 1958. Effects of a non-rigid, impermeable bottom on plane surface waves in shallow water. J. Mar. Res. 16: 61–82</ref>), the time scale <math>T_m</math> for viscous momentum dissipation in the fluid mud layer is given by <math>T_m = \pi h_m^2 / \nu_m</math>, where <math>h_m</math> is the thickness of the fluid mud layer and <math>\nu_m</math> the average kinematic viscosity of this layer. The dissipation of the surface wave energy is strongest when the time scale <math>T_m</math> is of the same order (slightly larger) as the wave period <math>T</math>. In this situation the wave motion in the fluid mud layer lags the surface wave by about <math>\pi/2</math>. Values of the viscosity <math>\nu_m</math> of the fluid mud layer cover a wide range of <math>10^{-4} - 10^{-1} m^2 s^{-1}</math> depending on the density<ref>Mehta, A.J. 2023. An Introduction to Hydraulics of Fine Sediment Transport. World Scientific Publ. Co.</ref>. Field observations at a mud bank on the Louisiana shelf show that during storm conditions the fluid mud layer contributes little to wave damping, as the lutocline is smoothened by strong turbulence. In contrast, a significant dissipation of wave energy in the mud layer is observed when the storm is waning, associated with a sharp lutocline formed by hindered floc settling and laminar flow in the mud layer<ref name=T15>Traykovski, P., Trowbridge, J. and Kineke, G. 2015. Mechanisms of surface wave energy dissipation over a high-concentration sediment suspension. J. Geophys. Res. Oceans 120: 1638–1681</ref>. The analysis of Gade suggests that a thin high-viscous layer just above the gelling mud deposit contributes most to wave damping.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">==Mud gravity flow==</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">Fluid mud can easily slide down a sloping bottom. A slope of about 1% is sufficient. But sliding down an even gentler slope is also possible. This is the case if sufficient external energy is supplied to maintain the mud in colloidal suspension. This could be surface wave energy absorbed in the fluid mud layer, as described above. Fluid mud flows that are maintained in this way are called wave-supported turbidity flows. They can occur during outflow of wave-dominated river deltas into the sea. At tide-dominated deltas, gravity mud flows onto the shelf can occur that remain suspended by tidal energy<ref name=M07/>.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">With insufficient slope or lack of external energy supply, the fluid mud layer collapses; the mud layer consolidates and becomes part of the soil substrate. Sedimentation is a slow process with a time scale approximately proportional to the square of the layer thickness. Mud gravity flows that feed by taking up sediment from the seafloor are called autosuspended turbidity currents. The density of these mud flows then increases and so does their speed. This type of mud flows can convey mud from shallower to deeper estuarine regions and cause silting up of artificially deepened navigation channels and harbors.</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
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Dronkers J
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Dronkers J at 12:56, 2 July 2023
2023-07-02T12:56:04Z
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 12:56, 2 July 2023</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The reduction in flow resistance is mainly due to the suppression of turbulence at the lutoclines<ref>Winterwerp, J.C., Manning, A.J., Martens, C., De Mulder, T. and Vanlede J. 2006. A heuristic formula for turbulence-induced flocculation of cohesive sediment. Estuarine, Coastal and Shelf Science 68: 195-207</ref>. The [[Bed roughness and friction factors in estuaries|friction factor]] <math>c_D</math> can be reduced by a factor 10 or even more.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>The reduction in flow resistance is mainly due to the suppression of turbulence at the lutoclines<ref>Winterwerp, J.C., Manning, A.J., Martens, C., De Mulder, T. and Vanlede J. 2006. A heuristic formula for turbulence-induced flocculation of cohesive sediment. Estuarine, Coastal and Shelf Science 68: 195-207</ref>. The [[Bed roughness and friction factors in estuaries|friction factor]] <math>c_D</math> can be reduced by a factor 10 or even more.</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Fluid mud layers are frequently observed at harbour entrances and in artificially deepened navigation channels<ref>Parker, G., Lanfredi, N.W. and Swift, D.J.P. 1982. Seafloor response to flow in a southern hemisphere sand ridge field: Argentine inner shelf. Sed.Geol.33: 195-216</ref><ref>De Jonge, V.N., Schuttelaars, H.M., Van Beusekom, J.E.E., Talke S.A. and De Swart, H.E. 2014. The influence of channel deepening on estuarine turbidity levels and dynamics, as exemplified by the Ems estuary. Estuarine, Coastal and Shelf Science 139: 46-59</ref>, see [[Siltation in harbors and fairways]]. Fluid mud layers in estuaries often form during neap tides in the high-water and low-water slack zones where saline and fresh water converge and where fine sediments are trapped, see Fig. 3 and [[Estuarine turbidity maximum]].   </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Fluid mud layers are frequently observed at harbour entrances and in artificially deepened navigation channels<ref>Parker, G., Lanfredi, N.W. and Swift, D.J.P. 1982. Seafloor response to flow in a southern hemisphere sand ridge field: Argentine inner shelf. Sed.Geol.33: 195-216</ref><ref>De Jonge, V.N., Schuttelaars, H.M., Van Beusekom, J.E.E., Talke S.A. and De Swart, H.E. 2014. The influence of channel deepening on estuarine turbidity levels and dynamics, as exemplified by the Ems estuary. Estuarine, Coastal and Shelf Science 139: 46-59</ref>, see [[Siltation in harbors and fairways]]. Fluid mud layers in estuaries often form during neap tides in the <ins class="diffchange diffchange-inline">[[Slack water|</ins>high-water and low-water slack<ins class="diffchange diffchange-inline">]] </ins>zones where saline and fresh water converge and where fine sediments are trapped, see Fig. 3 and [[Estuarine turbidity maximum]].   </div></td></tr>
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Dronkers J
https://www.coastalwiki.org/w/index.php?title=Fluid_mud&diff=80009&oldid=prev
Dronkers J at 15:06, 31 January 2023
2023-01-31T15:06:31Z
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 15:06, 31 January 2023</td>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>{{ Definition| title = Fluid mud  </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>{{ Definition| title = Fluid mud  </div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>| definition = Fluid mud is a high-concentration colloidal suspension of fine sediment particles (< 63 µm with a high percentage of clay particles < 2 µm). }}</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>| definition = Fluid mud is a high-concentration colloidal suspension of fine <ins class="diffchange diffchange-inline">cohesive </ins>sediment particles (< 63 µm with a high percentage of clay particles < 2 µm). }}</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
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<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>The concentration of fine cohesive sediments in suspension can become very high close to the seabed. <del class="diffchange diffchange-inline">This can be due </del>to<ref>McAnally, W.H., Friedrichs, C., Hamilton, D., Hayter, E., Shrestha, P., Rodriguez, H., Sheremet, A. and Teeter, A. 2007. Management of Fluid Mud in Estuaries, Bays, and Lakes. I: Present State of Understanding on Character and Behavior. J. Hydr. Eng. 133: 9-22</ref></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>The concentration of fine cohesive sediments in suspension can become very high close to the seabed. <ins class="diffchange diffchange-inline">Processes that contribute </ins>to <ins class="diffchange diffchange-inline">the formation of fluid mud are</ins><ref>McAnally, W.H., Friedrichs, C., Hamilton, D., Hayter, E., Shrestha, P., Rodriguez, H., Sheremet, A. and Teeter, A. 2007. Management of Fluid Mud in Estuaries, Bays, and Lakes. I: Present State of Understanding on Character and Behavior. J. Hydr. Eng. 133: 9-22</ref></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#Convergence of residual fine sediment transport related to [[Tidal asymmetry and tidal basin morphodynamics|tidal asymmetry]] and [[estuarine circulation]]. These processes are a major cause of the formation of a turbidity maximum in estuaries (see [[Estuarine turbidity maximum]]).  </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#Convergence of residual fine sediment transport related to [[Tidal asymmetry and tidal basin morphodynamics|tidal asymmetry]] and [[estuarine circulation]]. These processes are a major cause of the formation of a turbidity maximum in estuaries (see [[Estuarine turbidity maximum]]).  </div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>#<del class="diffchange diffchange-inline">Fluidisation </del>of consolidated mud deposits <del class="diffchange diffchange-inline">subjected </del>to wave-induced pressure variations. Once formed, the fluid mud layer is maintained by absorbing part of the wave energy. As a consequence, wave action can be strongly damped by absorption of wave energy in the fluid mud layer. The strong wave damping observed at muddy coasts (for example the coasts of Guiana and Surinam, see [[Coastal mud belt]]) is caused by the presence of extensive fluid mud banks<ref>Traykovski, P., Trowbridge, J. and Kineke, G. (2015) Mechanisms of surface wave energy dissipation over a high-concentration sediment suspension. J. Geophys. Res. Oceans 120: 1638–1681</ref>.  </div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>#<ins class="diffchange diffchange-inline">Stirring </ins>of <ins class="diffchange diffchange-inline">partially </ins>consolidated mud deposits <ins class="diffchange diffchange-inline">subject </ins>to wave-induced pressure variations. Once formed, the fluid mud layer is maintained by absorbing part of the wave energy. As a consequence, wave action can be strongly damped by absorption of wave energy in the fluid mud layer. The strong wave damping observed at muddy coasts (for example the coasts of Guiana and Surinam, see [[Coastal mud belt]]) is caused by the presence of extensive fluid mud banks<ref>Traykovski, P., Trowbridge, J. and Kineke, G. (2015) Mechanisms of surface wave energy dissipation over a high-concentration sediment suspension. J. Geophys. Res. Oceans 120: 1638–1681</ref>.  </div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#Settling of mudflocs into the near-bottom suspended layer, see [[Flocculation cohesive sediments]].</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>#Settling of mudflocs into the near-bottom suspended layer, see [[Flocculation cohesive sediments]].</div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Through these processes fine sediments become trapped in a colloidal suspension, called fluid mud.</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Through these processes fine sediments become trapped in a colloidal suspension, called fluid mud.</div></td></tr>
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Dronkers J
https://www.coastalwiki.org/w/index.php?title=Fluid_mud&diff=79817&oldid=prev
Dronkers J at 13:50, 31 August 2022
2022-08-31T13:50:54Z
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<td colspan="2" style="background-color: #fff; color: #222; text-align: center;">Revision as of 13:50, 31 August 2022</td>
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<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;"></ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>{{ Definition| title = Fluid mud  </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>{{ Definition| title = Fluid mud  </div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>| definition = Fluid mud is a high-concentration colloidal suspension of fine sediment particles (< 63 µm<del class="diffchange diffchange-inline">, </del>with <del class="diffchange diffchange-inline">often </del>a high percentage of clay < 4 <del class="diffchange diffchange-inline">µm</del>). <del class="diffchange diffchange-inline">It </del>is formed by <del class="diffchange diffchange-inline">settling </del>of mudflocs into <del class="diffchange diffchange-inline">a </del>near-bottom suspended layer at a higher <del class="diffchange diffchange-inline">rate </del>than the <del class="diffchange diffchange-inline">dewatering rate</del>, or by <del class="diffchange diffchange-inline">fluidization </del>and/or <del class="diffchange diffchange-inline">liquefaction </del>of <del class="diffchange diffchange-inline">an underconsolidated </del>mud <del class="diffchange diffchange-inline">bottom</del>. <del class="diffchange diffchange-inline">}}</del></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>| definition = Fluid mud is a high-concentration colloidal suspension of fine sediment particles (< 63 µm with a high percentage of clay <ins class="diffchange diffchange-inline">particles < 2 µm). }}</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">==Formation fluid mud layer==</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">[[File:fallconc.jpg|thumb|right|300px|Fig. 1. Floc settling velocity as a function of the concentration,</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">after Mehta (1986)<ref>Mehta, A.J. 1986. Characteristics of cohesive sediment properties and transport processes in estuaries. In: Estuarine cohesive sediment dynamics. Ed.: A.J.Mehta. Lecture notes coastal and estuarine studies 14, Springer-Verlag, Berlin: 427-445</ref>. High sediment concentrations produce larger flocs and higher settling velocities (upgoing branch I, fit to</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">experimental data: </ins><<ins class="diffchange diffchange-inline">math>\, w_s = 5. 10^{-</ins>4<ins class="diffchange diffchange-inline">} c^{1.3} \,</math> m/s</ins>). <ins class="diffchange diffchange-inline">Floc settling </ins>is <ins class="diffchange diffchange-inline">hindered at high suspension density (downgoing branch II, fit to experimental data <math>\, w_s = 2.6 \; 10^{-3} (1-0.008 \; c)^{4.65} \,</math> m/s).]]</ins></div></td></tr>
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<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">The concentration of fine cohesive sediments in suspension can become very high close to the seabed. This can be due to<ref>McAnally, W.H., Friedrichs, C., Hamilton, D., Hayter, E., Shrestha, P., Rodriguez, H., Sheremet, A. and Teeter, A. 2007. Management of Fluid Mud in Estuaries, Bays, and Lakes. I: Present State of Understanding on Character and Behavior. J. Hydr. Eng. 133: 9-22</ref></ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">#Convergence of residual fine sediment transport related to [[Tidal asymmetry and tidal basin morphodynamics|tidal asymmetry]] and [[estuarine circulation]]. These processes are a major cause of the formation of a turbidity maximum in estuaries (see [[Estuarine turbidity maximum]]). </ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">#Fluidisation of consolidated mud deposits subjected to wave-induced pressure variations. Once </ins>formed<ins class="diffchange diffchange-inline">, the fluid mud layer is maintained </ins>by <ins class="diffchange diffchange-inline">absorbing part of the wave energy. As a consequence, wave action can be strongly damped by absorption of wave energy in the fluid mud layer. The strong wave damping observed at muddy coasts (for example the coasts of Guiana and Surinam, see [[Coastal mud belt]]) is caused by the presence of extensive fluid mud banks<ref>Traykovski, P., Trowbridge, J. and Kineke, G. (2015) Mechanisms of surface wave energy dissipation over a high-concentration sediment suspension. J. Geophys. Res. Oceans 120: 1638–1681</ref>. </ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">#Settling </ins>of mudflocs into <ins class="diffchange diffchange-inline">the </ins>near-bottom suspended layer<ins class="diffchange diffchange-inline">, see [[Flocculation cohesive sediments]].</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Through these processes fine sediments become trapped in a colloidal suspension, called fluid mud.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">This occurs, for example, in periods around neap tide and near the seawater intrusion limit in turbid estuaries.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">When mudflocs settle, the suspended sediment concentration near the bottom increases. A dense suspension close to the seabed is formed in which further settling is impeded. There are several theories describing this so-called hindered settling regime<ref>Winterwerp, J.C. 2002. On the flocculation and settling velocity of estuarine mud. Cont. Shelf Res. 22: 1339-1360</ref><ref>Dankers, P.J.T. and Winterwerp, J.C. 2007. Hindered settling of mud flocs: Theory and validation. Continental Shelf Res. 27: 1893-1907</ref>. </ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">When the flocs fill almost all the space, an interconnected matrix of particle bonds is formed in the dense suspension. Sediment settling then becomes impossible. The sediment concentration </ins>at <ins class="diffchange diffchange-inline">which the space is completely filled is called the gelling concentration <math>c_{gel}</math>. The gelling concentration depends on the nature of the flocs. In some situations </ins>a <ins class="diffchange diffchange-inline">value of 40 g/l is found, but generally the value is </ins>higher<ins class="diffchange diffchange-inline">; <math> c_{gel} \approx</math> 100 g/l.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">[[File:Luto.jpg|thumb|left|450px|Fig. 2. Schematic representation of suspended sediment layers in a turbid estuary.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Turbulence is strongly suppressed at the interface between different layers, due to density stratification.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">This happens already at relatively low concentration differences of a few hundred mg/l <ref>Gust, G. and Walger, E. 1976. The influence of suspended cohesive sediments on boundary-layer structure and erosive activity of turbulent seawater flow. Mar.Geol. 22: 189-206</ref><ref>Li, M.Z. and Gust, G. 2000. Boundary layer dynamics and drag reduction in flows of high cohesive sediment suspensions. Sedimentol. 47: 71-86</ref>.]]</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">The settling velocity in the hindered settling regime depends on several factors. </ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Contacts with other flocs depend on <math>c/c_{gel}</math>; floc interaction decreases the settling velocity by a factor <math>(1-c/c_{gel})^m </math>.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">The weight of the floc in the dense suspension is lower </ins>than the <ins class="diffchange diffchange-inline">weight in clear water by a factor <math>(1-c/\rho_s)</math>, where <math>\rho_s</math> is the density of the suspension.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">The viscosity of the suspension is increased relative to the clear water viscosity <math>\nu</math> <ref>Dyer, K.R., Christie, M.C. and Manning, A. J. 2004. The effect of suspended sediment on turbulence within an estuarine turbidity maximum. Est. Coast. Shelf Sci. 59: 237-248</ref>.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">This increase amounts to a factor <math>(1+2.5 c/c_{gel})</math>, according to experimental evidence.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Altogether this leads to the following expression for the hindered settling velocity of fine cohesive sediment:</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"><math>w_s(c) = w_s(0) \Large\frac{(1-c/\rho_s)(1-c/c_{gel})^m}{1+2.5 c/c_{gel}}\normalsize , \qquad (1) </math></ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">where for the exponent the value <math>m=2</math> is used.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">A similar but more elaborated formula was proposed by Camenen<ref>Camenen, B. and Van Bang, D.P. 2011. Modelling the settling of suspended sediments for concentrations close to the gelling concentration. Continental Shelf Res. 31: 106-111</ref>; this formula includes the possibility that the flocs do not entirely fill all the space when the gelling point is reached.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"><br clear=all></ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Due to hindered settling</ins>, <ins class="diffchange diffchange-inline">the floc settling velocity decreases for concentrations around 10 kg/m<math>^3</math>. The maximum in the settling velocity curve (Fig. 1) implies that mass settling to the fluid mud layer converges to a concentration exceeding 10 kg/m<math>^3</math>. </ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">The suspended sediment concentration in fluid mud may even reach 250 g/l.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Buoyancy suppresses turbulent exchange between layers of different density,</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">stimulating the formation of a lutocline - a sharp interface between layers with different suspended sediment concentrations, see Fig. 2.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">The density difference between the layers is thereby further increased as an auto-enhancing process.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Winterwerp<ref>Winterwerp, J.C. 2001. Stratification effects by cohesive and non-cohesive sediments. J.Geophys.Res. 106: 22559-22574</ref> argues that the density increase may finally exceed the sediment carrying capacity of the lower layer, leading to the collapse of this layer and the formation of a mud bed. </ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">For further details on mud transport, mud bed formation and destruction see [[Dynamics of mud transport]].</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">==Hydrodynamics of fluid mud==</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">As long as the concentration is below the gel point, fluid mud can flow as a viscous near-bed layer, entrained by the flow </ins>or by <ins class="diffchange diffchange-inline">pressure gradients of the overlying water mass. Fluid mud layers can be entrained by near-bottom currents over considerable distances without being dispersed over the whole water column<ref>Kirby, R. </ins>and <ins class="diffchange diffchange-inline">Parker, W.R. 1983. Distribution and behaviour of fine sediment in the Severn Estuary and Inner Bristol Channel. U.K.Can.J.Fish.Aquat.Sci. 40 (suppl.): 83-95<</ins>/<ins class="diffchange diffchange-inline">ref>.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">If the seabed is sloping, the fluid mud slides down as a turbidity current under the influence of gravity. In shallow water, fluid mud absorbs wave energy.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">If near-bottom currents are absent </ins>or <ins class="diffchange diffchange-inline">very weak, the fluid mud layer consolidates and becomes part of the bed substrate. The consolidation process can take a long time, and is approximately proportional to the square </ins>of <ins class="diffchange diffchange-inline">the layer thickness.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">[[Image:FluidMudLoireEstuary.jpg|thumb|400px|right|Figure 3: Fluid </ins>mud <ins class="diffchange diffchange-inline">in the Loire estuary during neap tide and low fluvial discharge; km 0 corresponds to the estuarine mouth. Source: Christine Bertier (2011)<ref name=B> Bertier, C. 2011. Dynamique et suivi du bouchon vaseux dans l’estuaire de la Loire. Séminaire Technique sur le transport sédimentaire: Principes et expériences sur le bassin Ligrien, Vierzon 24 Novembre 2011</ref></ins>. <ins class="diffchange diffchange-inline">]]</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">A seabed covered with fluid mud offers almost no resistance to the flow in the overlying layer.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">Prandle<ref>Prandle, D. 2003. Relationships between tidal dynamics and bathymetry in strongly convergent estuaries. J.Phys.Ocean. 33: 2738-2750</ref> related the friction coefficient to the mud content of the sediment bed in many UK estuaries; </ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">he found evidence for a strong decrease of the friction coefficient with increasing mud fraction.</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins style="font-weight: bold; text-decoration: none;">The reduction in flow resistance is mainly due to the suppression of turbulence at the lutoclines<ref>Winterwerp, J.C., Manning, A.J., Martens, C., De Mulder, T. and Vanlede J. 2006. A heuristic formula for turbulence-induced flocculation of cohesive sediment. Estuarine, Coastal and Shelf Science 68: 195-207</ref>. The [[Bed roughness and friction factors in estuaries|friction factor]] <math>c_D</math> can be reduced by a factor 10 or even more.</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">==Notes==</del></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">Fluid </ins>mud <ins class="diffchange diffchange-inline">layers are frequently observed at harbour entrances and in artificially deepened navigation channels<ref>Parker, G., Lanfredi, N.W. and Swift, D.J.P. 1982. Seafloor response to </ins>flow <ins class="diffchange diffchange-inline">in </ins>a <ins class="diffchange diffchange-inline">southern hemisphere sand ridge field: Argentine inner shelf. Sed.Geol.33: 195</ins>-<ins class="diffchange diffchange-inline">216</ref><ref>De Jonge, V.N., Schuttelaars, H.M.</ins>, <ins class="diffchange diffchange-inline">Van Beusekom, J.E</ins>.<ins class="diffchange diffchange-inline">E</ins>., <ins class="diffchange diffchange-inline">Talke S.A. and De Swart</ins>, <ins class="diffchange diffchange-inline">H.E. 2014. The influence </ins>of <ins class="diffchange diffchange-inline">channel deepening on estuarine turbidity levels and dynamics, as exemplified by </ins>the <ins class="diffchange diffchange-inline">Ems estuary</ins>. <ins class="diffchange diffchange-inline">Estuarine, Coastal and Shelf Science 139: 46</ins>-<ins class="diffchange diffchange-inline">59</ins></<ins class="diffchange diffchange-inline">ref</ins>><ins class="diffchange diffchange-inline">, see [[Siltation in harbors </ins>and <ins class="diffchange diffchange-inline">fairways]]. Fluid mud layers in estuaries often form during neap tides in the high-water and low</ins>-<ins class="diffchange diffchange-inline">water slack zones where saline and fresh water converge and where fine sediments are trapped, see Fig. </ins>3 <ins class="diffchange diffchange-inline">and [[Estuarine turbidity maximum]].  </ins></div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del class="diffchange diffchange-inline">As long as the concentration is below the gel point (formation of an interconnected matrix of particle bonds) fluid </del>mud <del class="diffchange diffchange-inline">can </del>flow <del class="diffchange diffchange-inline">as </del>a <del class="diffchange diffchange-inline">laminar near</del>-<del class="diffchange diffchange-inline">bed layer</del>, <del class="diffchange diffchange-inline">entrained by the flow or by pressure gradients of the overlying water mass</del>. <del class="diffchange diffchange-inline">It can also flow as a gravity current along a slope</del>. <del class="diffchange diffchange-inline">At rest</del>, <del class="diffchange diffchange-inline">the fluid mud layer slowly consolidates - a process that can take a long time</del>, <del class="diffchange diffchange-inline">proportional to the square </del>of the <del class="diffchange diffchange-inline">layer thickness</del>. <del class="diffchange diffchange-inline">The sediment concentration of fluid mud layers exceed 10 kgm<sup></del>-<del class="diffchange diffchange-inline">3</del></<del class="diffchange diffchange-inline">sup</del>> and <del class="diffchange diffchange-inline">can reach more than 100 kgm<sup></del>-3<<del class="diffchange diffchange-inline">/sup</del>><del class="diffchange diffchange-inline">.</del></div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><<ins class="diffchange diffchange-inline">br clear=all</ins>></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">Fluid mud layers can arise from the pressure variations exerted by waves on an underconsolidated mud bottom. Once formed, the fluid mud layer absorbs part of the wave energy, so that wave action will be strongly damped.</del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>==<del class="diffchange diffchange-inline">See also</del>==</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>==<ins class="diffchange diffchange-inline">Related articles</ins>==</div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">:[[Dynamics of mud transport]] </ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">:[[Sediment deposition and erosion processes]]</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">:[[Flocculation cohesive sediments]]</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">:[[Coastal and marine sediments]]</ins></div></td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Mud]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Mud]]</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">:[[Dynamics of mud transport]]</del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Estuarine turbidity maximum]]  </div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Estuarine turbidity maximum]]  </div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><del style="font-weight: bold; text-decoration: none;">:[[Sediment deposition and erosion processes]]</del></div></td><td colspan="2"> </td></tr>
<tr><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Characteristics of muddy coasts]]</div></td><td class='diff-marker'> </td><td style="background-color: #f8f9fa; color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>:[[Characteristics of muddy coasts]]</div></td></tr>
<tr><td class='diff-marker'>−</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>:[[Coastal and marine <del class="diffchange diffchange-inline">sediments</del>]]</div></td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>:[[Coastal <ins class="diffchange diffchange-inline">mud belt]]</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">==References==</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline"><references/></ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">{{author</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">|AuthorID=120</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">|AuthorFullName=Job Dronkers</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">|AuthorName=Dronkers J}}</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div> </div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">[[Category:Physical coastal </ins>and marine <ins class="diffchange diffchange-inline">processes]]</ins></div></td></tr>
<tr><td colspan="2"> </td><td class='diff-marker'>+</td><td style="color: #222; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><ins class="diffchange diffchange-inline">[[Category:Sediment</ins>]]</div></td></tr>
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Dronkers J
https://www.coastalwiki.org/w/index.php?title=Fluid_mud&diff=78864&oldid=prev
Dronkers J: Created page with "{{ Definition| title = Fluid mud | definition = Fluid mud is a high-concentration colloidal suspension of fine sediment particles (< 63 µm, with often a high percentage of c..."
2021-03-27T14:17:02Z
<p>Created page with "{{ Definition| title = Fluid mud | definition = Fluid mud is a high-concentration colloidal suspension of fine sediment particles (< 63 µm, with often a high percentage of c..."</p>
<p><b>New page</b></p><div>{{ Definition| title = Fluid mud <br />
| definition = Fluid mud is a high-concentration colloidal suspension of fine sediment particles (< 63 µm, with often a high percentage of clay < 4 µm). It is formed by settling of mudflocs into a near-bottom suspended layer at a higher rate than the dewatering rate, or by fluidization and/or liquefaction of an underconsolidated mud bottom. }}<br />
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==Notes==<br />
As long as the concentration is below the gel point (formation of an interconnected matrix of particle bonds) fluid mud can flow as a laminar near-bed layer, entrained by the flow or by pressure gradients of the overlying water mass. It can also flow as a gravity current along a slope. At rest, the fluid mud layer slowly consolidates - a process that can take a long time, proportional to the square of the layer thickness. The sediment concentration of fluid mud layers exceed 10 kgm<sup>-3</sup> and can reach more than 100 kgm<sup>-3</sup>.<br />
<br />
Fluid mud layers can arise from the pressure variations exerted by waves on an underconsolidated mud bottom. Once formed, the fluid mud layer absorbs part of the wave energy, so that wave action will be strongly damped.<br />
<br />
<br />
==See also==<br />
:[[Mud]]<br />
:[[Dynamics of mud transport]]<br />
:[[Estuarine turbidity maximum]] <br />
:[[Sediment deposition and erosion processes]]<br />
:[[Characteristics of muddy coasts]]<br />
:[[Coastal and marine sediments]]</div>
Dronkers J