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Roger Weller, geology instructor regional geology planetary gems
Mariana Trench: The Bottom of the World
The Mariana Trench is located in the Pacific Ocean east of the Mariana Islands and not far from Japan. The name is instantly recognizable as the Trench holds the distinction of being the single deepest point on the planet.
The product of underwater subduction, the Trench is an incredible 1, 580 miles long and at its deepest point, known as the Challenger Deep, it is 35,838 feet deep according to the most recent sounding by the Japanese unmanned submersible Kaiko. This number is prone to some change however as different sources list it different ways. However all agree that the Challenger Deep is nearly 36,000 feet deep which equates to nearly seven miles of water between the ocean surface and the bottom of the Trench. The pressure at that depth is tremendous, an astonishing 108.6 MPa (Pascals) over a thousand times more pressure than the standard amount of pressure found at sea level.
Diagram owned by www.marianatrench.com
The Exploration of the Mariana Trench was first undertaken, successfully, in 1951 by the British survey ship, HMS Challenger. This survey ship's name eventually came to be the label for the deepest portion of the Trench as mentioned above. In the wake of the HMS Challenger came the Soviet survey ship, the Vityaz. The Vityaz surveyed the Trench in 1957 and claimed a depth of approximately 36,201 feet. A claim that has not been repudiated since with the advent of more modern technology.
The first completed
dive to the bottom of the trench came in 1960. It was accomplished by the US
Navy using the Swiss-built bathyscaphe Trieste.
As this picture is the product of a United States soldier taken in the line of duty it is public domain
The Trieste, the
spiritual forefather of the famous exploration craft Alvin, landed on the ocean
floor at the bottom of the Trench at 1:06 p.m. On the 23rd of January in 1960.
Jaques Piccard, a Swiss Oceanographer aboard the Trieste reported that the soil
at the bottom of the Challenger Deep was a fine silt ooze inhabited by shrimp,
soles, and flounder. Later investigations proved there was a much larger variety
of life inhabiting the Trench than Piccard could ever have expected.
Within the primordial ooze of the Challenger Deep there resides a protoform of life, called foraminifera, these single-cell organisms exist at the most extreme depths and are considered by some scientists to resemble some of the earliest forms of life on the planet.
foraminifera there are also the other denizens of the deepest realm, the Angler
Fish being the most classical example:
Photo owned by National Geographics
This is, of course, only a taste of what there is to know about the Mariana Trench in particular and the Oceans all together. It is a sad truth that more is known about the depths of space than the darkest regions of our own planet. Visionaries such as Jacque Custo saw mankind living at the bottom of the sea amidst the natural wonder of a world that is at once intimately familiar and inexorably alien.
Such a dream cannot
come to pass until humanity pulls its eyes from the stars and looks to what is
already available to it as a species.
Photo belongs to www.treehugger.com