Abyssal Plain of The Ocean

The deep-sea plains or abyssal plains are undulating underwater plains found on the deep ocean floor. Deep sea planes are gently sloping areas of the ocean basins. These are the flattest and smoothest regions of the world because of terrigenous [denoting marine sediment eroded from the land] and shallow water sediments that buries the irregular topography.

It covers nearly 40% of the ocean floor.
The depths vary between 3,000 and 6,000 m.
These plains are covered with fine-grained sediments like clay and silt.

Origin of Abyssal Plains

Tectonic plate movements are responsible for the formation of an abyssal plain, as are most changes in the Earth’s crust.
The lower oceanic crust melts as a result of activity in the Earth’s mantle, causing the seafloor to spread.
When the plates separate, magma can rise from beneath and cool, forming a new oceanic crust. As the process repeats itself, the crust will continue to spread.
Abyssal plains act like a blanket, smoothing out the hard crust on oceanic ridges and seabed over time. On the ocean floor, sediments, silt, and natural detritus accumulate.
These sediments, which range from clay and volcanic ash to sand, gravel, or silt, contain organic matter such as plant matter, parts of decaying organisms, or microscopic organic matter.
Pollutants like chemical precipitates and trash from nearby continental coasts can add to the natural silt.
As these sediments accumulate, they form level or gently sloping plains that rise from the ocean floor as they cover it. These plains are around a kilometre thick on average.
This shows how abyssal plains take a long time to form because they are made up of such microscopic particles and trash.

Examples of Abyssal Plains

The Sohm plain is the world’s largest abyssal plain. This plain is located in the North Atlantic Ocean, south of Newfoundland and Canada’s Maritime region.
The Colombian Abyssal Plain is another example of a huge abyssal plain on Earth. The Colombian plain is exceedingly flat, with a very gradual slope, and reaches depths of up to 14,260 feet, or around 4,350 metres.

Characterstics of Abyssal Plains

Flat and rolling Submarine plains.
Their depth ranges from 300 metre to 6000 metre in sea.
This is the most extensive relief of Oceanic Bottom.
About 75.9% of Oceanic relief is Deep sea Plains, it’s proportion in Pacific Ocean is 80.3%, while in Indian Ocean it is 80% but in Atlantic Ocean it is only 54.9%.
The more extensive Continental Shelves found in the Atlantic Ocean result in very little extension of Deep sea Plains.
Deep Sea Plains comprises various ridges, some of them come out of the oceans.
Examples– Mid Atlantic Ridge, Indian Ocean Ridge, East Pacific Ridges etc.
Deep sea plains are also characterizes by pelagic deposits of plants, marine animals, and siliceous remains, with no presence of terrigenous materials.
Volcanic deposits are also found in some oceans but in limits proportion.

FAQs on Abyssal Plains

Ques 1. What are abyssal plains?

Answer: Abyssal plains are vast, flat regions of the ocean floor that lie at great depths, typically between 3,000 and 6,000 meters (9,800 to 19,700 feet). They are the most extensive and level areas in the world’s oceans, characterized by sediment-covered, gently sloping terrain.

Ques 2. How are abyssal plains formed?

Answer: Ocean currents from various sources, such as rivers, volcanic eruptions, and biogenic processes, carry fine sediment, including clay, silt, and organic particles, and settle it on the ocean floor over millions of years, primarily forming abyssal plains.The gradual deposition of these materials results in the creation of the flat and featureless abyssal plains.

Ques 3. What is the significance of abyssal plains?

Answer: Abyssal plains play a crucial role in oceanic ecosystems and geological processes. Their sediment-rich environment supports unique and diverse deep-sea life forms, including various invertebrates, bacteria, and specialized organisms adapted to extreme conditions. Additionally, the fine sediments on abyssal plains act as a repository for organic carbon and other materials, contributing to global carbon cycling. Furthermore, these regions are essential for scientific research and exploration, helping us better understand Earth’s history, geology, and marine biodiversity.

Read Also : Continental Slope of The Ocean