Screenshot of Northeast U.S. Canyons Expedition: Live footage. |
Leg 2 - Dives 4 & 5
During the last two days, the team of the Okeanos Explorer has left the canyons behind to travel some 100 plus kilometers to explore the Mytilus Seamount, which is a previously unexplored seamount belonging to the New England Seamount Chain. Dive 4 was spent on the north side while dive 5 on the south side, resulting in a diversity of marine life between the two. This has been an incredibly enlightening experience but, as the scientists themselves have admitted, there are more questions than answers.
Seamounts
Seamounts are underwater mountains created by volcanic activity. Magma pushing up through the oceanic crust, acting similar to terrestrial volcanoes, are the result of hot spots in the earth's crust. They do not reach the surface of the ocean so they are not considered islands or even atolls, though both have developed similarly. Now most are extinct volcanoes that can reach as high as 4,000 meters from the seafloor, and since they are so abrupt, have been known to be the source of grave danger to ships and submarines.
This elevation of rock from the seafloor also poses other consequences. Scientists desire to know more about these seamounts due to the changes they create in the oceans current, and therefore, the weather. The greatest danger is extrusion seepage in the seamount that eventually causes the sides to collapse, resulting in a landslide, which has the potential to induce tsunamis.
Screenshot of Northeast U.S. Canyons Expedition: Live footage. |
And yet, the resulting upwelling produces an above-average population of plankton making it prime property for suspension feeders like coral and bivalves. In their observations of the Mytilus seamount, the Okeanos team have noted many variances of marine life. At the base of the seamount, where the substrate was soft, fishes such as the frogfish and a few species of eel were present but not in great quantities. Moving on up the seamount, the substrate became rockier and large basalt ledges were observed covered in a drape of sediment. There were a great many occurrences of bamboo and black corals, often with associates like squat lobster and brittle stars. Added to these were sea cucumbers, sea lilies, hermit crabs, and even some barnacles.
Unfortunately, there are no known hydrothermal vents in the New England Seamount Chain (NESC). This is unfortunate because hydrothermal vents and their symbiotic communities absolutely fascinate me. In such excruciatingly hot temperatures, there is still life, and life uncommon to any other ocean biome. This is a topic all its own. But to my dismay, it won't be part of this expeditions logs.
The New England Seamount Chain is said to have evolved over a period of a hundred million years. But what if a series of consecutive catastrophic events created them in just a fraction of that time? What if there was a physical upheaval that caused the present geographic situation?
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