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How deep is the Mariana Trench?

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Map graphic showing the boundaries of the five oceans-Pacific, Atlantic, Indian, Arctic, and Southern-using color-coded regions. Four different map projections are included: North Pole view, South Pole view, International Date Line view, and Greenwich Meridian view, each displaying the oceans' extents around the continents. — ocean Earth's oceans and their marginal seas cover nearly 71 percent of the planet's surface.

The Mariana Trench is the deepest known deep-sea trench on Earth, located in the western Pacific Ocean. Determining its exact maximum depth is challenging due to the technical difficulties of taking measurements at such extreme depths, and various expeditions have reported different values over time.12

The greatest depths are found within the Challenger Deep, a steep-walled valley on the floor of the trench. Estimates for the depth of the Challenger Deep vary, with some scientific reports citing approximately 10,935 meters (35,876 feet), while other measurements have reached up to 11,034 meters (36,201 feet) or 11,033 meters (36,198 feet). These variations reflect the ongoing evolution of sonar and electronic sounding technology used to map the ocean floor.234