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In oceanography, terrigenous sediments are those derived from the erosion of rocks on land; that is, they are derived from terrestrial (as opposed to marine) environments. [1] Consisting of sand , mud , and silt carried to sea by rivers , their composition is usually related to their source rocks; deposition of these sediments is largely ...
Marine sediment, or ocean sediment, or seafloor sediment, are deposits of insoluble particles that have accumulated on the seafloor.These particles either have their origins in soil and rocks and have been transported from the land to the sea, mainly by rivers but also by dust carried by wind and by the flow of glaciers into the sea, or they are biogenic deposits from marine organisms or from ...
Terrigenous sediment is the most abundant sediment found on the seafloor. Terrigenous sediments come from the continents. These materials are eroded from continents and transported by wind and water to the ocean. Fluvial sediments are transported from land by rivers and glaciers, such as clay, silt, mud, and glacial flour.
The continental shelves are covered by terrigenous sediments; that is, those derived from erosion of the continents. However, little of the sediment is from current rivers; some 60–70% of the sediment on the world's shelves is relict sediment, deposited during the last ice age, when sea level was 100–120 m lower than it is now. [21] [11]
This is due to the transport of terrigenous sediments by methods such as rivers and wind from the continents. The terrigenous sediment buries most accumulated organic material, preventing enough biological material from being present for it to be classified as biogenous. Distribution of biogenous sediments is determined by three factors: [1]
The sediment can consist of terrigenous material, which originates on land, but may be deposited in either terrestrial, marine, or lacustrine (lake) environments, or of sediments (often biological) originating in the body of water. Terrigenous material is often supplied by nearby rivers and streams or reworked marine sediment (e.g. sand). In ...
Most of the material in the accretionary wedge consists of marine sediments scraped off from the downgoing slab of oceanic crust, but in some cases the wedge includes the erosional products of volcanic island arcs formed on the overriding plate. An accretionary complex is a current (in modern use) or former accretionary wedge.
The DFW Metroplex sprawls across a 100 kilometers (62 mi) wide N-S trending belt of outcropping Cretaceous sediments. Fort Worth in the west is neatly built on Early Cretaceous (Comanche Series) and Dallas in the east is built on Late Cretaceous (Gulf Series) sediments. The Cretaceous rocks of the Comanche Series were deposited over a 20 ...