Trenches – Mariana

Not that I want to digress from my routine blogging, but from this day forward I thought I would start posting articles that have caught my eye, things that I find interesting, and the likes.

I’m pretty much a water bug. I love the water even though I despise getting wet in the rain or getting into a swimming pool in normal clothing – this because I don’t like being in wet clothes – but it has done nothing to deter my affection from swimming or the water, seas and oceans included. When I was in the second grade, I read 20,000 Leagues Under the Sea and was for a period of time obsessed with Captain Nemo, Nautilus, and all the fathomless depths of the oceans. I remember sitting with an encyclopedia and reading all I could about water, rivers, lakes, seas and oceans, and my dad, being a Geography buff decided it was time I got a bigger and more detailed atlas. Brilliant thing, those books are. Beautiful illustrations, etc. So anyway, I was with the atlas and discovered, by chance, the word ‘trench’. Overcome by curiosity, I quickly searched and read all I could about trenches. The result, my discovery of the Marianna Trench. It’s not the only thing that caught my eye at the time, but it is one of the most fascinating things I’ve ever come across.

At least 22 trenches have been identified although not all are classified as major. Of this number, 18 are in the Pacific Ocean, three in the Atlantic Ocean, and one in the Indian Ocean.

The Mariana Trench is located in the Pacific Ocean, just east of the 14 Mariana Islands (11″21′ North latitude and 142″ 12′ East longitude ) near Japan. It is the deepest part of the earth’s oceans, and the deepest location of the earth itself. It was created by ocean-to-ocean subduction, a phenomena in which a plate topped by oceanic crust is subducted beneath another plate topped by oceanic crust.
The deepest point of the Mariana Trench is called The Challenger Deep , so named after the British exploration vessel HMS Challenger II and it is located 210 miles south-west of Guam. This depth was reached in 1960 by the Trieste, a manned submersible owned by the U.S. Navy.
In order to better illustrate the actual depth of the Mariana Trench, consider the following; if Mount Everest, which is the tallest point on earth at 8,850 meters (29,035 feet), were set in the Mariana Trench, there would still be 2,183 meters (7,166 feet) of water left above it.

The deepest part of the ocean is called the abyssal zone. It is host to thousands of species of invertebrates and fish including such oddities as the Angler Fish so called because it uses a bioluminescent (life light) protrusion to attract its prey. The Challenger Deep in the Mariana Trench is very cold, and highly pressurized; its floor features hydrothermal (hot water ) vents formed by spreading tectonic plates which release hydrogen sulfide and
other minerals which are consumed by the barophilic bacteria which are then consumed by other microorganisms, which are in turn, consumed by the fish, and so on. The temperature around the vents can reach up to 300° Celsius (572° Fahrenheit). The venting fluid is highly acidic, while the water from the deep ocean is slightly basic. Although the venting fluid is prevented from boiling due to its dissipation into the surrounding freezing water, creatures from the deep show an incredible resistance to temperature extremes by having different proteins which are adapted for life under these conditions; allowing the animals to eat, process food, and reproduce. One animal which thrives near hydrothermal vents is the Bythograea thermydron, of “Vent Crab” – their numbers are so vast that scientists are using the crab clusters to locate hydrothermal vents.
Crabs and Angler Fish are but few of the many species of the Mariana Trench. One mud sample taken from Challenger Deep by Oceanographers from the Kaiko yielded nearly over 200 different microorganisms. Although there seems to be an abundance of life at these depths, no human being could withstand the pressure extremes.Another interesting characteristic of these deep sea creatures is their longevity; many of these animals having a lifespan of over one hundred years, provided of course that they do not end up in fishing nets. Since these creatures seldom migrate and are slow to develop, there is growing concern over their endangerment.

 

The ocean floor at such depth consists of pelagic sediment, also known as biogenous “ooze”. Pelagic sediment is composed of shells, animal skeletons, decaying microorganisms and plants; it is generally yellowish and very viscous. While plants and other organisms on the planet’s surface convert water, minerals and carbon dioxide into nutrients by gathering light in their pigments through the process of photosynthesis, the plants and microorganisms of the deep use a process called chemosynthesis to convert the chemically rich discharge of hydrothermal vents into food.

Hydrothermal vents, also called “black smokers” are chimney like undersea geysers which spew out sea water which has seeped in and come in contact with the hot volcanic core. The discharge of hydrothermal vents is a black smoke which contains a variety of chemicals and dissolved metals, which are then consumed or processed by the microorganisms, animals, and plants. Vents which have been active for a long period grow to resemble chimneys; some of them reaching heights of over 15 meters (49 feet).
As before, certain deep-sea animals feature bioluminescent appendages and features which serve a wide variety of purposes, from mating to self-preservation, and even hunting, as is the case with the Angler Fish. Bioluminescence is light generated by a living organism as the result of an internal chemical reaction. The only surface animal which features this ability is the Pyractomena borealis, also known as the Firefly.

No, I did not write it on my own… If you’re interested you can visit the site where I got the information from http://www.marianatrench.com
Enjoy the exploration !!