Tuesday, January 22, 2008

Deep Sea Vents

Deep Sea Vents or Hydrothermal Vents

Deep Sea Vents or Hydrothermal Vents

Deep Sea Hydrothermal Vent image courtesy: treehugger.com


Sea-bottom a mysterious and intriguing


The ocean bottom remained a mystery; from time immemorial generations have dreamt about the fairies and mermaids, dreaded about fierce ghosts and demons and fantasized about the ocean bottom caves filled with gold and diamonds. Here is a poem about those serene gems!


Full many a flower is blown to blush unseen;

And waste its sweetness in the desert air.

Full many a gem of purest ray serene,

The dark unfathomed caves of ocean bear.


It is the fantasy that fills the gap between the real and the virtual, imagination rides with child hood stories; there may be a cave full of gems awaiting a boy who went for fishing but sunk beneath the sea, mermaid who lived in gem-studded palaces on sea bottom welcome him offering him a life to ‘live happily ever after’! Ghosts from beneath the deep see roam on ocean surface in search of sailor’s to suck their blood.


But this is about the ‘deep sea vents and the living things around it’! They are also gems; but of a ‘different ray serene’ in the ‘dark unfathomed caves of ocean’.


Geysers


Deep Sea vents or deep sea hydrothermal vents are geysers that form along with mid ocean ridges. These are just cracks in the ocean bottom in to which ocean water gushes in to be ejected out along with various minerals available with the magma. These vents are places where the magma of the earth’s core gets some exit points.


It was in 1977 some scientists exploring the ocean bottom near Galapagos Island came across with this phenomenon. The innumerable living things, their shapes and the way that lived depending upon these deep sea vents really intrigued them. This discovery was an eye opener to the scientists who so far believed that these deep dark places under severe pressure were devoid of higher forms of living things.


How are they formed?


Deep Sea Vents or Hydrothermal VentsDeep Sea Vents explained diagram courtesy: wikimedia.org

The earth is made up of a core of molten rock called the magma. Its surface is covered by huge plates of solidified magma that we call rock, they are ‘tectonic plates’ for the scientists. These rock-plates called the tectonic plates on which we live float on the molten magma like gigantic ships on sea. At times they collide causing earth-quakes. From the gaps between these plates magma oozes out lava and form and huge mountain ranges and islands, all begin with the volcanoes! Those volcanoes under the sea when interact with ocean form the deep sea vents.


The Mariana Trench


The floor of the ocean as we know is very deep; some points like the Mariana Trench which is the deepest part on the earth; has a depth of 11 km and a surface pressure 108 million pound / sq inch (any man if exposed to this pressure get squeezed and dies within seconds). It is so deep that it can easily swallow Mount Everest if placed in to it!). Sunlight never penetrates in to these trenches and their temperature is always near freezing point.


An unknown phenomenon!


Deep Sea Vents or Hydrothermal VentsDeep Sea Vents - Fisher brisingids




But nature never neglects these trenches and those innocent beings who have to live there; it provides them with ‘deep sea vents’ so that they may get some warmth, nutrients and ambient eco system; only for ‘specially adapted beings’ to live in peace and darkness! They don’t have to fear predators of any sorts even if they enter these zones it will be only as decayed dead bodies. The only problem is the lack of light; they don’t realize it as light is an unknown phenomenon to them.


Ocean bottom exploration


Deep Sea Vents or Hydrothermal VentsDeep Sea Vents image courtesy: rps.psu.edu

Exploration of ocean bottom was not possible beyond a depth of 125 meters as even deepest divers could not go beyond that depth; due to the scarcity of modern equipments. The arrival of Jim Suit extended that depth to 600 meters, yet the deep sea vents that was located around 2100 meters could remain elusive. Bathyscaphe that was designed for deep sea exploration could go up to 1829 meters was a real revolution in deep sea exploration. Alvin an advanced bathyscaph changed the scope and for the first time these deep sea vents, tube worms, eye-less shrimps, vent crab all came before human observation.


Hot smokers!


Deep Sea Vents or Hydrothermal VentsDeep Sea Vents mussels image courtesy: mbari.org

There are two types of hydrothermal vents some of them are ‘hot smokers’ of the deep sea! among the hot smokers those which go on spitting black smoke are known as ‘black smokers’, they emit sulphides and iron, these two chemicals combine to form iron monosulphate which is black in color. The other type is ‘white smokers’ they emit water comparatively cooler than ‘black smokers’ and contain calcium, barium silicon etc. and hence known as ‘smokers’.


Chimneys


These smokers are provided with ‘chimneys’ which are formed of mineral compounds emitted from the vents. The minerals that come out mixed with the super hot water enters in the cold ocean water and get subjected to sedimentation. These sediments accumulate around the vents in the form of chimneys. The speed in which these formed is astonishing it may grow as fast as half a meter in a month! There height at times make them collapse but fast get rebuilt.


The inmates of the hot waters!


Deep Sea Vents or Hydrothermal VentsDeep Sea Vents Seaworm image courtsey: cardboardmonocle.com

This super hot water that eject from the vents and the freezing cold water of the deep sea bottom mix up to give a peculiar atmosphere for some of the organisms like the


Tube worms (Riftia pachiptilia) cylindrical animals 8 feet in length, with no mouth, eye, stomach etc!


Vent crab (Brythograea thermydron), an active predator of the deep sea vents, its young ones look bright red while adults are white in color and reach maximum size of 5 inches.


Pompeii worm (Alvinella popejana) a strange creature capable to stand utmost heat (even in boiling water), in this case it breaks the record of the Sahara desert ants.


Bacteria (ancient type) they are believed to be the most primitive type untouched by evolutions or mutation.


What an idea!


Deep Sea Vents or Hydrothermal VentsDeep Sea Vents image courtesy: bact.wisc.edu

This ecology exists free from sunlight; no plants to make carbohydrate out of sunlight because there is no sunlight! The animals living here produce food by another technology. They harbor millions of bacteria in their body and engage in a symbiotic relationship with them. Bacteria convert the nutrients contained in the hot mineral-rich water that comes out of the deep sea vents in to edible food. The food is consumed by the animals and in exchange the bacteria get free lodging in the animal body. The only thing is; this marriage is made in heaven one cannot survive without the other; united we stand; divided we fall, what an idea for quarrelling couples!

No comments:

Google