The Abyssal Plains

Located 3,000-6,000 meters below the waves, vast floors of sediment stretch across the planet’s ocean basins. These areas, known as the abyssal plains, were once mysteries to researchers and explorers. Devoid Picture of hydrothermal vents - (Photo courtesy Marius Hepp / EyeEm Premium / Getty Images)

Picture of hydrothermal vents - (Photo courtesy Marius Hepp / EyeEm Premium / Getty Images)

of light, two degrees Celsius, and crushed by 300 atm of water pressure, these expanses covering fifty percent of the ocean floor were thought to be uninhabitable. However, as time passed and additional research was conducted, scientists have now discovered that the abyssal plains are home to some of the most unique ecosystems on Earth.

Discovery

In 1872, the HMS Challenger set out on an expedition to map the sea floors. Using basic sounding equipment, consisting of a weighted hemp rope dropped to the ocean floor, the crew was able to make a rough estimate of sea depths. The research revealed long stretches of flat plains uninterrupted by other land masses, a feature confirmed by the Jeanette and Fram expeditions nearly a decade later.
Finally, in 1947, sonar devices known as fathometers were used by Tolstoy and Elwing to officially confirm the existence of the Sohm Abyssal Plain south of Newfoundland. Using similar technology, the existence of other plains was soon established.

Unique Ecosystems

Initial sonar findings led scientists to believe that the abyssal plains were devoid of life. However, deep-sea submersibles, which are submarine vessels capable of withstanding extreme pressures and temperatures, soon discovered fascinating ecosystems thriving in this desolate environment.
The first ecosystems discovered were the hydrothermal vents. These geological features are chimneys that stem from the oceanic crust and spew hot minerals such as iron, sulfide, and calcium into the water at temperatures near 750 degrees Fahrenheit. Such extreme heat would seem to prevent life from residing here, but archaic bacteria have made these vents their home. Capable of performing chemosynthesis, the production of energy from chemicals instead of sunlight, the bacteria make food for themselves and also for the foundation of an ecological community.
Feathery, red tube worms sprout out like weeds from the vents, their interiors rich with bacteria. Following the tube worms are crabs, bivalves, and even fish, all of which are capable of withstanding the extreme heat and pressure. This hydrothermal vent ecosystem is thought to be a window into a primitive earth, as life thrives despite the absence of sunlight.
Additionally, geologic features resembling underwater lakes bloomed before the submersible as it scanned the ocean floor. Known as cold seeps, these areas exist where gases are squeezed from the ocean crust by the immense water pressure. The escaping gases, especially sulfur, combine with the dense saltwater to form large pools on the ocean floor. Surrounding these sites, the researchers in the submersibles found more worms filled with chemosynthetic bacteria in addition to clams, crabs, shrimp, and small fish.

Deep Sea Resources

As the supplies of the world have begun to dwindle, the abyssal plains are now being looked to for resources. For example, they are being researched as potential dumping grounds for old oilrigs, large ships, munitions, and hazardous chemicals. In theory, the high pressures of the water could crush the waste and reabsorb it into the ocean crust. Eventually, this waste material could be reconverted into a harvestable energy source.
Similarly, oil and fuel deposits already present beneath the surface of the plains are being sought out for energy sources. However, accidents such as the Deepwater Horizon oil spill make harvesting fuels a risky endeavor. Further drilling innovations are needed in order to prevent future accidents. On the other hand, deep-water mining does not carry with it the same risks for disaster. The mineral riches of the plains are substantial, especially in the form of polymetallic nodules. These potato-sized lumps of valuable minerals can simply be lifted from the seafloor and brought to the surface.
One final resource of the abyssal plains is the stock of marine life. As the supply of fish near the surface begins to dwindle, fishermen turn to the plentiful communities of the deep. However, deep-sea fish are slow growing and the deep-water ecosystems are thought to be very old. Fast-paced harvesting could be extremely destructive and easily wipe out entire communities. Therefore, more research must be conducted before humans involve themselves any further in the mysteries of the abyssal plains.

The Abyssal Plains