Mariana Trench

I think that the Mariana Trench is the most interesting feature in any ocean. I have also wondered about this part of the ocean (before I was in university) because I knew only that it was the deepest part of the ocean, and that we knew next to nothing about the landscape of life that resides in the trench. I remember my grade 12 global geography teacher was trying to make a point about how little relief is actually on the planet, and he drew a large quarter of a circle across three chalk boards to represent the earth, and then drew in a little peak about an inch high representing Everest and a trench about the same size and said it was Mariana Trench. I also remember him saying that if you cut off Mount Everest and put it inside the Trench that it would fit in and still have a few kilometers until the ocean surface. I think that is what made me interested in the Trench. It is 11,034 meters below sea level and is located south of Japan and east of the Philippines, close to Guam. The Trench is part of a subduction zone where the Pacific plate is being subducted under the Philippine plate. It was first surveyed by the Royal Navy vessel Challenger in 1951. The scientists used echo sounding techniques to estimate its depth at 11,022m. It was later estimated that its depth was 10,911 meters, but most recently (as of February 6, 2007), the trench was measured at 11,034, making the initial estimate at its depth more accurate than subsequent guesses.

In 1960, a dive was attempted in the United States Navy Bathyscape named "Trieste" with the hopes of reaching the bottom of the trench. U.S. Navy Lieutenant Don Walsh and Jaques Piccard were on board, and at 1:06pm on January 23, the bathyscape hit the bottom. The pressure was measured at 1,086 bar, or 15,751 psi, which is approximately 1000 atmospheres greater than at the surface. There have been other estimates at its depth and pressure by other countries, but all estimates seem to be within 50 meters of each other. Marianas Trench has also been a part of popular culture as it is referred to in several movies including Deep Rising, The Core (where the team of scientists try to reach the centre of the Earth and start their journey by entering the asthenosphere through Mariana Trench) to name a few. It has also been mentioned in several novels and songs.

I also find it very interesting how little we know about the trench. It has been stated in the Oceans course that we know less about the oceans than we do about Mars, and seeing as Mariana Trench is the deepest part of any ocean, to me it is like another planet except we know that there IS life there and we still have much to learn. I think about how little we know about the Trench at this point in my life, and I wonder how much we will know when I am 40, 60, or 80 years old (knock on wood). The problem that I see with these discoveries is that with so many other issues to focus on, exploring the deep sea is not on the top of the global scientific priority list (when compared to issues such as global warming, solving world hunger, etc.) and therefore it may be several decades to centuries before these discoveries are made.

(for this writeup, I used Wikipedia as well as marianatrench.com)