ScienceDaily (Feb. 14, 2010) Evidence from the Challenger Deep -- the deepest surveyed point in the world's oceans -- suggests that tiny single-celled creatures called foraminifera living at extreme depths of more than ten kilometres build their homes using material that sinks down from near the ocean surface.
The Challenger Deep is located in the Mariana Trench in the western Pacific Ocean. It lies in the hadal zone beyond the abyssal zone, and plunges down to a water depth of around 11 kilometres.
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