Seabed Landforms, Sediments, Ecosystems, and Human Impacts

All flashcards

What is the typical sequence of seabed regions from a continent toward the deep ocean?

Continental shelf, continental slope, continental rise, and abyssal plain.

How do oceanic trenches form?

They form at some plate boundaries and are among the deepest parts of the ocean.

What are the four major marine sediment types classified by origin?

Terrigenous, biogenous, hydrogenous, and cosmogenous sediments.

What is the benthos?

The ecological community associated with the seabed and deepest waters, including organisms on and within sediments.

How do ships use acoustic technology to map the seabed?

They send sound signals through water and use their returns from the seabed to measure depth and map topography.

Quiz questions

1. Which type of marine sediment comes from land?Answer: Terrigenous sediment.
2. At roughly what depth does calcium carbonate dissolve enough that calcareous ooze is generally not found below it?Answer: About 4,000–5,000 m.
3. What does the term benthos describe?Answer: The ecological community associated with the seabed and deepest waters.
4. How do ships use acoustic signals to map underwater topography?Answer: They measure sound signals that return from the seabed.
5. What can bottom trawling do to seabed environments?Answer: Disturb sediments and seabed habitats.