Name / Description

Mariannas Trench

Type

Currents, Trenches, Ridges, and Streams

Discoverer

0

Additional Notes

Marianas Trough , or Marianas Deep , elongated depression on the floor of the Pacific Ocean, c.210 miles SW of Guam. Deepest known depression on the earth's surface. First sounded in 1959 by Soviet scientists; its bottom was reached in 1960 by 2 men in the U.S. Navy bathyscaphe Trieste . In March 1995 the remote-controlled Japanese deep-sea probe Kaiko touched bottom at 35,798 ft,1 possibly marking the actual limit of the deep.