Deep ocean minerals not only by its mineral density but cold temperature, cleanliness and trace elements. DOW is present at depths of between 250 and 1500 meters. This deep ocean current moves very slowly under the influence of density and temperature gradients. The high mineral density is attributed to the depth related pressure and the change in temperature from 20 °C+ at the surface to 8 °C at 600 meters depth generates the movement of this layer. "Very deep ocean water" has been discovered in a number of troughs in the Atlantic and Pacific Oceans. Depths can range from 1500 meters to 15
Challenger Deep of ± On 31 May 2009 the United States sent the "Nereus" hybrid remotely operated vehicle (HROV) to the Challenger Deep. Nereus thus became the first vehicle to reach the Mariana Trench since 1998 and the deepest-diving vehicle then in operation. Project manager and developer Andy Bowen heralded the achievement as "the start of a new era in ocean exploration". "Nereus", unlike "Kaikō", did not need to be powered or controlled by a cable connected to a ship on the ocean surface. "Nereus" spent over 10 hours at the bottom of the Challenger Deep and measured a depth of at