The most common sediment in lakes is clay and silt.
The clastic material over most of a lakes basin is made up of silts and clays, especially away from any river mouths or shores where larger material is deposited.
In lake bottoms, the most common form of sediment is clay, which is the finest (smallest) particle size of clastic sediments.
Clastic sediments are organized by grain size, ranging in descending order from boulder to cobble, pebble, sand, silt, and finally clay.
Common sedimentary rocks include sandstone, limestone, and shale.
These rocks often start as sediments carried in rivers and deposited in lakes and oceans. When buried, the sediments lose water and become cemented to form rock.
Lacustrine deposits are sedimentary rock formations which formed in the bottom of ancient lakes.
A common characteristic of lacustrine deposits is that a river or stream channel has carried sediment into the basin.
Sediment can come from soil erosion or from the decomposition of plants and animals.
Wind, water and ice help carry these particles to rivers, lakes and streams.
Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz.
Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension with water.
Silt usually has a floury feel when dry, and lacks plasticity when wet.
Sediment is a naturally occurring material, derived from the weathering and erosion of underlying bedrock and steam banks, which is then subsequently transported downstream.
However, excessive sediment can significantly impact the condition of freshwater habitats, resulting in a deterioration of water quality.
Fine grained clastics are deposited in non-agitated water, calm water, where there is little energy to continue to transport the small grains.
Thus mudrocks form in deep water ocean basins and lakes.