continental rise. found in passive regions where trenches are absent; a thick accumulation of sediments at the bottom of the continental slope; sediments cascade down the continental slope in turbidity currents (dense sediment laden water) and pile up at the continental rise. continental shelf.

Beyond this slope is the abyssal plain (C), a smooth and nearly flat area of the ocean floor. In some places, deep, steep-sided canyons called trenches (G) cut into the abyssal plain.

Structure. A continental shelf typically extends from the coast to depths of 100–200 metres (330–660 feet). It is gently inclined seaward at an average slope of about 0.1°. In nearly all instances, it ends at its seaward edge with an abrupt drop called the shelf break.

Continental slopes are regions of steeply sloping seafloor that lie between continental shelves and the deep ocean basins (Figure 2). Regional gradients are typically 2–5°, but locally slopes may be much steeper.

Continental slopes are the edges of continental blocks, the zones of change from continental crust to oceanic crust. They are critical links in the chain of sedimentary processes that eventually carry sediment to the true ocean basin floor.

Continents are the seven main divisions of land on Earth. A continental shelf extends from the coastline of a continent to a drop-off point called the shelf break. From the break, the shelf descends toward the deep ocean floor in what is called the continental slope. The widths of the continental shelves vary.

Pacific Ocean

The continental slope (often referred to simply as “the slope”) is commonly dissected by submarine canyons; faulting, rifting and slumping of large blocks of sediment can form steep escarpments, relatively flat terraces and (under certain conditions) basins perched on the slope.

A continental slope is most similar to which land feature? A cliff.

Although the continental slope averages about 4°, it can approach vertical on carbonate margins, on faulted margins, or on leading-edge, tectonically active margins. Steep slopes usually have either a very poorly developed continental rise or none at all and are called escarpments.

Answer: Although the continental slope averages about 4°, it can approach vertical on carbonate margins, on faulted margins, or on leading-edge, tectonically active margins. Steep slopes usually have either a very poorly developed continental rise or none at all and are called escarpments.

The continental rise is a low-relief zone of accumulated sediments that lies between the continental slope and the abyssal plain. It is a major part of the continental margin, covering around 10% of the ocean floor.

The continental rise completely surrounds Antarctica covering 39.4% of the Southern Ocean (see Table), forming a halo of sediment surrounding the Antarctic continent. Example of continental rise (in yellow) and submarine fan (red) adjacent to the coast of southeastern Brazil.

The broad, gentle pitch of the continental shelf gives way to the relatively steep continental slope. The more gradual transition to the abyssal plain is a sediment-filled region called the continental rise.

The continental rise is the gently inclined slope between the base of the continental slope and the deep ocean floor. It overlies the ocean crust bordering the faulted and fractured continental margin. It is the ultimate site of accumulation of sediment shed from the continent into the deep sea.

Active continental margins are those that are tectonically active, such as along much of the Pacific coast. Active margins are marked by earthquakes, volcanoes, and mountain belts. Unlike passive margins, they lack a continental rise and abyssal plain.

Deep-Sea Ecology The continental slopes extend gradually from the continental shelf break to the continental rise (c. 3000 m depth), with an average gradient of around 4°.

Oceanographers believe that abyssal plains are so flat because they are covered with sediments that have been washed off the surface of the continents for thousands of years. On the abyssal plains, these layers of sediment have now covered up any irregularities that may exist in rock of the ocean floor beneath them.

The abyssal zone is surprisingly made up of many different types of organisms, including microorganisms, crustaceans, molluscan (bivalves, snails, and cephalopods), different classes of fishes, and a number of others that might not have even been discovered yet.

Deep sea plains are gently sloping areas of the ocean basins. These are the flattest and smoothest regions of the world. The depths vary between 3,000 and 6,000m. These plains are covered with fine-grained sediments like clay and silt.

Lying between the foot of a continental rise and a mid-ocean ridge, abyssal plains cover more than 50% of the Earth’s surface. They are among the flattest, smoothest and least explored regions on Earth.

abyssal plains

10,000 feet

The ocean floor is called the abyssal plain. Below the ocean floor, there are a few small deeper areas called ocean trenches. Features rising up from the ocean floor include seamounts, volcanic islands and the mid-oceanic ridges and rises.

The bottom of the deep sea has several features that contribute to the diversity of this habitat. The main features are mid-oceanic ridges, hydrothermal vents, mud volcanoes, seamounts, canyons and cold seeps.

Islands are not floating at all. They are actually mountains or volcanos that are mostly underwater. Their bases are connected to the sea floor. If an island does disappear under the ocean, it’s because the land underneath has moved or the bottom of the volcano has broken apart.