The Mariana Trench was formed through subduction. The maximum known depth is between 10,994 & 11,034 metres in its floor known as the Challenger Deep. The worlds deepest-diving manned submersible. When oceanic crust connected by a passive margin to continental crust completely subducts beneath a continent, an ocean basin closes, and continental collision begins. These same adaptations may also hold a key to understanding the origins of ocean life, as scientists examine the genetics of these organisms to piece together the history of how life spread between isolated hadal ecosystems and eventually throughout the worlds oceans. Video Animation of India crashing into Asia, by Tanya Atwater. When mixed with asthenospheric material above the plate, the volatile lower the melting point of the mantle wedge, and through a process called flux melting it becomes liquid magma. And what exactly is living in its depths? Nothing, and sometimes this does happen. Theyre sometimes described as living fossils due to their eery appearance. "James Cameron on Earth's Deepest Spot: Desolate, Lunar-Like. All Rights Reserved. In particular, ocean trenches are a feature of convergent plate boundaries, where two or more tectonic plates meet. 51. When you have two pieces of continetnal crust running into each other, one is more or less dense that the other. Smith, A. L. & Roobol, M. J. Mt. Create Your Free Account or Sign In to Read the Full Story. How do we reverse the trend? B) an oceanic-oceanic convergent Some of the many strange animals living in the Mariana Trench include: The dumbo octopus is a small, pelagic umbrella octopus that resembles Dumbo from the 1941 Disney film. It is located east of the Mariana Islands, and at the time, it was believed to be 26,850 feet or 8,184 meters. The vast submarine slopes and steep walls of trenches make up much of the hadal zone, where unique habitats extending across a range of depths are home to diverse number of species, many of which are new or still unknown to science. If dropped from sea level, they would reach 400 miles per hour just before they hit the bottom and it would take about 40 seconds for them to reach it. This feature is called the accretionary wedge, mlange, or accretionary prism. Extensional back-arc faults pull rocks and chunks of plates apart. (Creative Studio, Woods Hole Oceanographic Institution). plate boundaries Trench exploration to date has been extremely limited (only three humans have ever visited the seafloor below 6,000 meters) and much of what is known about trenches and the things that live there has been derived from two sampling campaigns in the 1950s (the Danish Galatheaand the Soviet VitjazExpeditions) and from a handful of photographic expeditions and seafloor samples taken remotely from the deep with little knowledge of their precise location.