Oceanography (2+1)

Relief of Sea floor

Introduction

A sequence of major bathymetric (sea floor) regions can be identified in the and it  extends seaward from the coast. These include the continental shelf, continental slope, continental rise, abyssal plains, abyssal hills, ocean ridges and ocean trenches. Additionally, numerous minor features are recognized within these regions such as submarine canyons, submarine fans, knolls and seamounts.

Continental Shelf: The nearly flat plains, or terraces, at the top of the sedimentary wedge beneath the drowned edges of the continents are continental shelves. They average about 60 kilometers  in width. Local and regional variations , ranging from more than 1,000 kilometers in the Arctic. Ocean to a few kilometers along the Pacific coasts of North and South Africaare common. The continented shelf bottom, slopes gently seaward at an angle of about 0.5 degrees. This is very slight and impossible to detect with the naked eye. Continental shelves end on the ocean side as the shelf break where the sea bottom steepens appreciably. Continental shelf breaks occur, on a water depth of about 130 meters , but can be found deeper than 200 meters.