Suspended load
Encyclopedia
Suspended load is the portion of the sediment
that is carried by a fluid flow which settle
slowly enough such that it almost never touches the bed. It is maintained in suspension by the turbulence in the flowing water and consists of particles generally of the fine sand
, silt
and clay
size
.
and suspended load is not straightforward because whether a particle is in suspension or not depends on the flow velocity – it is easy to imagine a particle moving between bed load, part-suspension and full suspension in a fluid with variable flow. Suspended load generally consists of fine sand, silt and clay size particles although larger particles (more coarse sands) may be carried in the lower water column in more intense flows - further blurring the line between bed load and suspended load.
between 0.8 and 1.2.
Sediment
Sediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....
that is carried by a fluid flow which settle
Settling
Settling is the process by which particulates settle to the bottom of a liquid and form a sediment. Particles that experience a force, either due to gravity or due to centrifugal motion will tend to move in a uniform manner in the direction exerted by that force...
slowly enough such that it almost never touches the bed. It is maintained in suspension by the turbulence in the flowing water and consists of particles generally of the fine sand
Sand
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...
, silt
Silt
Silt is granular material of a size somewhere between sand and clay whose mineral origin is quartz and feldspar. Silt may occur as a soil or as suspended sediment in a surface water body...
and clay
Clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...
size
Particle size (grain size)
Particle size, also called grain size, refers to the diameter of individual grains of sediment, or the lithified particles in clastic rocks. The term may also be applied to other granular materials. This is different from the crystallite size, which is the size of a single crystal inside the...
.
Composition
The boundary between bed loadBed load
The term bed load or bedload describes particles in a flowing fluid that are transported along the bed. Bed load is complementary to suspended load and wash load.Bed load moves by rolling, sliding, and/or saltating ....
and suspended load is not straightforward because whether a particle is in suspension or not depends on the flow velocity – it is easy to imagine a particle moving between bed load, part-suspension and full suspension in a fluid with variable flow. Suspended load generally consists of fine sand, silt and clay size particles although larger particles (more coarse sands) may be carried in the lower water column in more intense flows - further blurring the line between bed load and suspended load.
Velocity
Suspended load is carried within the lower to middle part of the water column and moves at a large fraction of the mean flow velocity of the stream, with a Rouse numberRouse number
The Rouse number is a non-dimensional number in fluid dynamics which is used to define a concentration profile of suspended sediment and which also determines how sediment will be transported in a flowing fluid...
between 0.8 and 1.2.
See also
- SedimentSedimentSediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....
- Sediment transportSediment transportSediment transport is the movement of solid particles , typically due to a combination of the force of gravity acting on the sediment, and/or the movement of the fluid in which the sediment is entrained...
- Rouse numberRouse numberThe Rouse number is a non-dimensional number in fluid dynamics which is used to define a concentration profile of suspended sediment and which also determines how sediment will be transported in a flowing fluid...
- Bed loadBed loadThe term bed load or bedload describes particles in a flowing fluid that are transported along the bed. Bed load is complementary to suspended load and wash load.Bed load moves by rolling, sliding, and/or saltating ....
- Wash loadWash loadWash load is the portion of sediment that is carried by a fluid flow, usually in a river, such that it always remains close the free surface . It is in near-permanent suspension and is transported without deposition, essentially passing straight through the stream...
- Dissolved loadDissolved loadDissolved load is the term for material, especially ions from chemical weathering, that are carried in solution by a stream. The dissolved load contributes to the total amount of material removed from a catchment. The amount of material carried as dissolved load is typically much smaller than the...