The ocean is a very mysterious place. In fact, most of the ocean has yet to be discovered. However, scientists have found the deepest part of the ocean, the Mariana Trench.
The Mariana Trench is located east of the Mariana Islands in the Western Pacific, and it is surrounded by many unique environments. The Mariana Trench contains the deepest points on earth known to humans. The Challenger Deep, located in the southern end of the Mariana Trench is the deepest spot in the entire ocean. Since the trench is home to the deepest known points on earth, underwater vents bubble up liquid sulfur and carbon dioxide. Although the trench is of course difficult to measure from the surface considering it being the deepest spot in the ocean, its depth, at the deepest point, Challenger Deep, is estimated to be 36,070 feet. Mount Everest is the world's tallest mountain, and it stands at 29,026 feet above sea level. With that being said, the deepest part of the Mariana Trench is 7,044 feet deeper than Everest is tall. The trench has a length of about 1,580 miles, which is more than five times the length of the Grand Canyon. Hopefully these comparisons give you a visual image of how deep the Mariana Trench really is.
This map shows where the Mariana Trench and the Challenger Deep is located.
How was the trench formed?
The Mariana Trench was formed by the process that occurs in a subduction zone, where two gigantic layers of oceanic crust collide. One piece of oceanic crust pushes underneath another piece. When the two pieces finally overlap, a deep trench forms at the bend of the sinking crust. In this case, the Pacific Ocean crust is bending below the Philippine Crust, creating the Mariana Trench. Considering how deep the Mariana Trench is, it’s a bit surprising that it is not the closest spot in the ocean to the earth's center. But actually, the radius at the poles is around 16 miles smaller than the radius at the equator, since the earth bulges at the equator. So, portions of the seabed of the Arctic Ocean are closer to the core of the Earth than the Challenger Deep.
Volcanoes The Mariana Trench contains a chain of volcanoes that rise above the waves creating the Mariana Islands. The Eifuku submarine volcano spews liquid carbon dioxide from vents that act similar to chimneys when they let out smoke from fires. The liquid is 217 degrees Fahrenheit. At another submarine volcano called Daikoku, scientists discovered a pool of molten sulfur 1,345 feet below the earth's surface.
Life in the Trench
Although it may not seem like it, the Mariana Trench is home to a variety of wildlife. Animals living in the deepest parts of the trench had to adapt with the harsh conditions such as the extreme pressure and darkness. Since the bottom of the trench is so far from land, leaves and coconuts are not reliable food sources for the marine life living in the trench for they cannot easily travel down thousands of feet of water, so some micro organisms rely mainly on the chemicals in the water including methane or sulfur, while bigger animals rely on creatures lower in the food chain. The three most common organisms at the bottom of the Mariana Trench are xenophyophores, amphipods and holothurians also known as small sea cucumbers.
Although these creatures may not look familiar, they do live in the Mariana Trench.
With the trench being such a deep part of the ocean, it acts as a potential place for discarded litter and pollutants. A case study led by Newcastle University shows that chemicals that were banned in the 1970s are still present in even the deepest parts of the ocean.