Question

Ocean floor is divided into _____ parts.

• A. one
• B. two
• C. three
• D. four

Answer 1

Answer: (D)

The topography at the floor of the oceans is divided into four sections:

1. The Continental Shelf: The Continental Shelf is that part of an ocean that lies close to the continental margin. The depths of the shelves vary from 150 to 200 meters.

2. The Continental Slope: The Continental slope lies beyond the continental shelf, where the ocean floor slopes downwards. The steep slope connects the continental shelf with the deep ocean floor. The average depth of the slope varies from 3000 to 6000 meters.

3. The Ocean Trough: The Continental slope ends at the ocean trough, which is like a deep, underwater plain. It consists of islands, mountain ranges, plateaus, deep valleys and plains. These features cover about 40% of the oceans’ floors. Mid- Atlantic Ridge is the largest mountain range in the ocean. This range is over 1400 km in length

4. The Ocean Deeps: Trenches are formed deep in the oceans. Ocean trenches are long, narrow depressions on the seafloor. These chasms are the deepest parts of the ocean—and some of the deepest natural spots on Earth.