World's Most Extreme Deep-Sea Vents Revealed:

Deeper Than Any Seen Before, and Teeming With New Creatures

http://www.sciencedaily.com/releases/2012/01/120110114434.htm

120110114434.jpg

Beebe Vent Field shrimp. (Credit: Image courtesy of National Oceanography Centre, Southampton (UK))


ScienceDaily (Jan. 10, 2012) — Scientists have revealed details of the world's most extreme deep-sea volcanic vents, 5 kilometres down in a rift in the Caribbean seafloor.

The undersea hot springs, which lie 0.8 kilometres deeper than any seen before, may be hotter than 450°C and are shooting a jet of mineral-laden water more than a kilometre into the ocean above.

Despite these extreme conditions, the vents are teeming with thousands of a new species of shrimp that has a light-sensing organ on its back. And having found yet more 'black smoker' vents on an undersea mountain nearby, the researchers suggest that deep-sea vents may be more widespread around the world than anyone thought.

Reporting in the scientific journal Nature Communications this week, a team led by marine geochemist Dr Doug Connelly at the National Oceanography Centre in Southampton and marine biologist Dr Jon Copley of the University of Southampton has revealed details of the world's deepest known 'black smoker' vents, so-called for the smoky-looking hot fluids that gush from them.

During an expedition in April 2010 aboard the Royal Research Ship James Cook, the scientists used the National Oceanography Centre's robot submarine called Autosub6000 and a deep-diving vehicle, HyBIS, manufactured by the British firm, Hydro-Lek to locate and study the vents at a depth of five kilometres in the Cayman Trough, an undersea trench south of the Cayman Islands.

The vents, which the team named the Beebe Vent Field after the first scientist to venture into the deep ocean, are gushing hot fluids that are unusually rich in copper, and shooting a jet of mineral-laden water four times higher into the ocean above than other deep-sea vents. Although the scientists were not able to measure the temperature of the vents directly, these two features indicate that the world's deepest known vents may be hotter than 450 ºC, according to the researchers. "These vents may be one of the few places on the planet where we can study reactions between rocks and 'supercritical' fluids at extreme temperatures and pressures," says Connelly.

The team found a new species of pale shrimp congregating in hordes (up to 2,000 shrimp per m2) around the six-metre tall mineral spires of the vents. Lacking normal eyes, the shrimp instead have a light-sensing organ on their backs, which may help them to navigate in the faint glow of deep-sea vents. The researchers have named the shrimp Rimicaris hybisae, after the deep-sea vehicle that they used to collect them.

The Cayman shrimp is related to a species called Rimicaris exoculata, found at other deep-sea vents 4,000 kilometres away on the Mid-Atlantic Ridge. Elsewhere at the Beebe Vent Field, the team saw hundreds of white-tentacled anemones lining cracks where warm water seeps from the sea bed. "Studying the creatures at these vents, and comparing them with species at other vents around the world; will help us to understand how animals disperse and evolve in the deep ocean," says Copley.

The researchers also found black smoker vents on the upper slopes of an undersea mountain called Mount Dent. Mount Dent rises nearly three kilometres above the seafloor of the Cayman Trough, but its peak is still more than three kilometres beneath the waves. The mountain formed when a vast slab of rock was twisted up out of the ocean floor by the forces that pull the plates of Earth's crust apart.

"Finding black smoker vents on Mount Dent was a complete surprise," says Connelly. "Hot and acidic vents have never been seen in an area like this before, and usually we don't even look for vents in places like this." Because undersea mountains like Mount Dent may be quite common in the oceans, the discovery suggests that deep-sea vents might be more widespread around the world than previously thought.

The vents on Mount Dent, which the team has named the Von Damm Vent Field to commemorate the life of geochemist Karen Von Damm, are also thronged with the new species of shrimp, along with snake-like fish, and previously unseen species of snail and a flea-like crustacean called an amphipod. "One of the big mysteries of deep-sea vents is how animals are able to disperse from vent field to vent field, crossing the apparently large distances between them," says Copley. "But maybe there are more 'stepping stones' like these out there than we realised."

The UK expedition that revealed the vents followed a US expedition in November 2009, which detected the plumes of water from deep-sea vents in the Cayman Trough. A second US expedition is currently using a deep-diving remotely operated vehicle to investigate the vents further and the UK team also plans to return to the Cayman Trough in 2013 with Isis, the National Oceanography Centre's deep-diving remotely operated vehicle, which can work at depths of up to six kilometres.
 
"The vents, which the team named the Beebe Vent Field after the first scientist to venture into the deep ocean, are gushing hot fluids that are unusually rich in copper"

Perhaps in the future they will tap into these rich mineral deposits.
 
Would a ton of copper pouring out into the ocean be a concern? I read that and was kinda shocked, or would it even matter. I just know it's been such a feared thing with our reef tanks if copper would ever get into them
 
The creatures that live around these vents have evolved to withstand the extremely high temperatures (hotter than 450 ºC or 842º F.) & high concentrations of heavy metals.

The big question is how do vent creatures get from one vent to others when so far apart or do they evolve in each vent into similar organisms. I would assume these vent creatures can't survive in normal ocean parameters. :)
 
Another thought:

It is thought that these creatures may have been the first to develop in ancient hostile earth history, so perhaps these creatures evolved into the ones we see commonly around reefs. Could these vent creatures be the oldest living orgnansims here on earth? ;)
 
Wow that is really interesting isn't it. I think that kind of stuff is why we are in this hobby, I can remember back 15 years when I first setup a saltwater tank I was more amazed by what I might see in the sand or coming out of the rock than the fish and first corals I had.

Well maybe we can look forward to a special about. it I was just watching the giant Squid one last night.
 
That was really neat and I had no idea there suction cups contained those teeth like that, I was under the impression they were just smooth disc. Interesting about the whale if they can indeed knock out or stun there pray with sonar.
 
wow, that must be a wierd place full of wierd things. can not imagine.

will a man become the shrimp size if he dive to that deep ? :rolleyes:
 
Yes an man would be quite compressed at those depths.

http://en.wikipedia.org/wiki/Hydrothermal_vent

From it:

"Due to the high hydrostatic pressure at these depths, water may exist in either its liquid form or as a supercritical fluid at such temperatures. At a pressure of 218 atmospheres, the critical point of (pure) water is 375 °C. At a depth of 3,000 meters, the hydrostatic pressure of sea water is more than 300 atmospheres (as salt water is denser than fresh water). At this depth and pressure, seawater becomes supercritical at a temperature of 407 °C (see image). However the increase in salinity at this depth pushes the water closer to its critical point. Thus, water emerging from the hottest parts of some hydrothermal vents can be a supercritical fluid, possessing physical properties between those of a gas and those of a liquid.[2][3] Besides being superheated, the water is also extremely acidic, often having a pH value as low as 2.8 "” approximately that of vinegar."
 
What's really cool is how liquids behave when they become supercritical: ;)

From Wikipedia, the free encyclopedia

"A supercritical fluid is any substance at a temperature and pressure above its critical point, where distinct liquid and gas phases do not exist. It can effuse through solids like a gas, and dissolve materials like a liquid. In addition, close to the critical point, small changes in pressure or temperature result in large changes in density, allowing many properties of a supercritical fluid to be "fine-tuned". Supercritical fluids are suitable as a substitute for organic solvents in a range of industrial and laboratory processes. Carbon dioxide and water are the most commonly used supercritical fluids, being used for decaffeination and power generation, respectively

In addition, there is no surface tension in a supercritical fluid, as there is no liquid/gas phase boundary. By changing the pressure and temperature of the fluid, the properties can be "œtuned" to be more liquid- or more gas-like. One of the most important properties is the solubility of material in the fluid. Solubility in a supercritical fluid tends to increase with density of the fluid (at constant temperature). Since density increases with pressure, solubility tends to increase with pressure. The relationship with temperature is a little more complicated. At constant density, solubility will increase with temperature. However, close to the critical point, the density can drop sharply with a slight increase in temperature. Therefore, close to the critical temperature, solubility often drops with increasing temperature, then rises again.[2]

All supercritical fluids are completely miscible with each other so for a mixture a single phase can be guaranteed if the critical point of the mixture is exceeded. The critical point of a binary mixture can be estimated as the arithmetic mean of the critical temperatures and pressures of the two components,
Tc(mix) = (mole fraction A) x TcA + (mole fraction B) x TcB.
For greater accuracy, the critical point can be calculated using equations of state, such as the Peng Robinson, or group contribution methods. Other properties, such as density, can also be calculated using equations of state.[3]"
 
Fascinating stuff. Another non human component to the acidification of the oceans. It is amazing how little we really know about the great depths. I wish it would be made a scientific priority, much as the space program was in the sixties.
 
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