Mariana Trench
The Mariana Trench or Marianas Trench is located in the western Pacific Ocean about 200 kilometres east of the Mariana Islands; it is the deepest oceanic trench on Earth. It is crescent-shaped and measures about 2,550 km in length and 69 km in width. The maximum known depth is 10,984 metres at the southern end of a small slot-shaped valley in its floor known as the Challenger Deep. However, some unrepeated measurements place the deepest portion at 11,034 metres. If Mount Everest were hypothetically placed into the trench at this point, its peak would still be underwater by more than two kilometres. At the bottom of the trench, the water column above exerts a pressure of 1,086 bars, more than 1,071 times the standard atmospheric pressure at sea level. At this pressure, the density of water is increased by 4.96%. The temperature at the bottom is 1 to 4 °C. In 2009, the Marianas Trench was established as a US National Monument.
