Author Question: Create a table detailing the four types of marine sediments and their source (parent) material. ... (Read 59 times)

jessicacav · **on:** Aug 22, 2018

Create a table detailing the four types of marine sediments and their source (parent) material.

What will be an ideal response?

Question 2

Briefly describe how submarine canyons are created.

What will be an ideal response?

mceravolo · **Reply #1 on:** Aug 22, 2018

Answer to Question 1

Lithogenous sediments come from rivers, coastal erosion, landslides, glaciers, turbidity currents, wind-blown dust, and volcanic eruptions. Biogenous sediment comes from the shells of micro- and macro-organisms including coral reefs. Hydrogeneous sediment comes from the precipitation of minerals directly from sea water. Cosmogeneous sediment comes from space dust and meteorites.

Answer to Question 2

Submarine canyons are narrow but deep v-shaped valleys resembling canyons on land that occur on the edges of continental shelves and rises. Although it was initially thought that submarine canyons were created by river erosion when sea level was lower, the majority of canyons are deeper (3,500 meters) and were never exposed. Instead, both direct and indirect observations suggest that turbidity currents are responsible for carving submarine canyons, in which sediments on the continental shelf accumulate and flow rapidly, especially after a seismic event, down the continental rise.