Continental margin

It is one of the three major zones of the ocean floor, the other two being deep-ocean basins and mid-ocean ridges.

[5] At the shelf break begins the continental slope, which can be 1–5 km above the deep-ocean floor.

[4] Active continental margins are typically narrow from coast to shelf break, with steep descents into trenches.

[3] From this, comes a wide variety of features, such as low-relief land extending miles away from the beach, long river systems and piles of sediment accumulating on the continental shelf.

[3] Often found on passive margins are several kilometres of sediment, consisting of terrigenous and carbonate (biogenous) deposits.

These sediment reservoirs are often useful in the study of paleoceanography and the original formation of ocean basins.

[4] Due to the rise of offshore drilling, mining and the limitations of fisheries off the continental shelf, the United Nations Convention on the Law of the Sea (UNCLOS) was established.

[2] Such resources include fishing grounds, oil and gas accumulations, sand, gravel, and some heavy minerals in the shallower areas of the margin.