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A freak sharing his freakness about Geology!!

Deepest volcanic eruption – Recorded!

See the recent “underwater Fourth of July” scientists believe is the deepest volcanic eruption ever seen–with three-foot-wide lava bubbles and flows creeping over the seafloor.

Researchers witnessed a spectacular, fiery underwater volcano explosion, and captured it on video. It’s believed to be the deepest ocean volcano eruption ever recorded.

The undersea Pacific Ocean explosions in May of this year were recorded using a remote operating vehicle. Under the tone of the vehicle motors, recorded by a hydrophone, you can hear the muffled sounds of the explosions, still audible under 4,000 feet of ocean water.

An expedition team, which included researchers from the University of Washington and the National Oceanic and Atmospheric Administration, was conducting observations in an area of the Pacific bounded by the island nations of Samoa, Tonga and Fiji.  The eruption was southeast of Samoa.

One of the lead scientists called it, ‘an underwater Fourth of July.’  Images show large molten lava bubbles about three feet across [molten_lava]; glowing red vents ejecting lava into the sea, and lava flows across the seafloor [eruption_and_magma].

This “West Mata (MAH-TAH)” volcano stands more than a mile high off the ocean floor. Its eruptive area is about the length of a football field. It is producing Boninite (BOH nih nite) lavas, believed to be among the hottest erupting on Earth in modern times. Researchers believe they have a unique chance to study magma formation and how the Earth recycles material where tectonic plates slide against each other.

A microbiologist on the team found diverse microbes in the extreme conditions, and they observed a small species of shrimp thriving. It’s believed to be the same shrimp species found at eruptive sites more than 3,000 miles away.

Mission scientists believe 80 percent of eruptive activity on Earth occurs in the ocean, and most volcanoes are in the deep sea.  But until this discovery, NOAA and the National Science Foundation had sponsored submarine volcano research for 25 years, without observing a deep-ocean eruption like this one, which is now recorded for all of us to see.

Turbidite Facies

A turbidite facies tract (FT) was defined by Mutti (1977, 1992) as :

” The lateral association of genetic facies that can be observed within an individual bed or a package of strictly time-equivalent beds”

Although facies tracts develop both in crosscurrent and along-current directions, lateral facies tracts refer primarily to facies changes that are observed in a direction parallel to the flow. The recognition of facies tracts suffers from two main limitations:

(i) The first is related to the fact that facies tracts can only be established within precise time-correlation patterns, i.e., within thin stratigraphic units that are physically traceable over significant areas.

(ii) The second limitation is represented by the very low-gradient facies variations that most systems undergo over the available outcrop areas.

In terms of facies, Walker (1984) considered a set of sedimentary features characterizing the classical turbidite deposits, as follows:

1- Sandstones and shales are monotonously inter-bedded through many tens or hundred of meters of stratigraphic sections. Beds tend to have flat tops and bottoms, with no scouring and channeling on a scale greater than a few centimetres.

2) Sandstones beds have sharp, abrupt bases, and tend to grade upward into finer sand, silt and mud. Much of the mud was brought into the basin by the turbidity current (it contains a shallow water transported faunal assemblage), but the uppermost very fine clay may contain a bathyal or abyssal benthonic fauna and hence represent slow hemipelagic deposition between turbidity current events.

3) On the undersurface (sole) of the sandstone beds there are abundant markings, now classified into three types. Tool marks carved into the underlying mud by rigid objects /sticks, stones) in the turbidity current; scour marks cut into the underlying muds by fluid scour; and organic markings representing trails and burrows filled by the turbidite current. Tool and scour marks give accurate indications of local paleoflow directions, and by now, many thousands have been measured to reconstruct paleoflow patterns in hundreds of turbidite basins.

4) Within the sandstone beds, combinations of parallel lamination, ripple cross lamination, climbing ripple cross lamination, convolute lamination and graded bedding have been noted by many authors.

An ideal, or generalized succession (or sequence) of facies was proposed by Bouma (1962), and the Bouma sequence, illustrated in figure, can be regarded as an excellent facies model for classical turbidites, that is to say, those which consist of monotonous alternations of sandstones and shales, parallel bedded without significant scouring or channeling and where all the beds can reasonably be described using the Bouma sequence . This classical model seems to fit better with those gravity flows associated with significant relative sea level falls (Vail’s model).

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In a complete Bouma sequence, five divisions can be considered : A) Massive or graded bedding interval ; B) Sandy parallel laminations ; C) Rippled and /or convoluted ; D) Delicate parallel interlaminations of silt and mud and E) Mud introduced by the turbidity current and hemipelagic background mud of the basin. As illustrated, in the lower part of the figure, the organization of a turbidite sequence facies changes with its position in the fan and so with the velocity of the current. Updip, facies A are those of debris flows ; Facies B, quite rich in sand like those of traction currents ; Facies C is the classic turbidite with a complete Bouma sequence (a-b-c-d-e) ; Facies D, rich in ,thin beds, quite developed bottom-truncated Bouma sequence (b-c-d-e, c-d-e or d-e). In the fringes (lower fans), the sediments are thin. They are, often reworked by sea floor current, which following continent contours are called contour currents. The reworked sediments exhibit current ripples and forms, and are called contourites by geoscientists.

Plate024[1]

A complete Bouma sequence, as illustrated in the previous plate, begins with a graded division A, which is overlain by parallel laminated division B and cross-laminated division C. In this example, the facies D and E are very thin, almost invisible, due to erosion or non-deposition. As said previously, bottom sea currents, erode, often, the upper divisions, since turbidite currents can erode the substratum on which they flow. The erosion depend mainly on the density of the current and the type of sediments that it transport.

Formation of New Land (delta growth) in Louisiana

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Delta growth, Louisiana
Most of the Mississippi River delta plain is losing ground, but new land is forming in Atchafalaya Bay at the mouths of the Wax Lake Outlet and the Atchafalaya River. Wax Lake Outlet is an artificial channel built to reduce the severity of floods in Morgan City, Louisiana. The Atchafalaya is a distributary of the Mississippi River. Combined, their deltas grow an estimated 2.8 square kilometers (1.1 square mile) per year. Floods transport large amounts of sediment to Atchafalaya Bay, while hurricanes redistribute sediment within the bay and destroy coastal vegetation that would otherwise protect land from erosion.

Mystifying Shelf Life

Imagine a place where there are 131 frog-eating bats, 34,140 Cretaceous Molluscs, 40 terabytes of data of stars, planets and galaxies, and to top that 86,881 samples of tissues and DNA. Where we have samples from the field of Paleontology, Anthropology, Vertebrate and Invertebrate Zoology, and Physical Sciences. This is the place where global history resides and preserved. This is the American Museum of Natural History.

The Shelf life collection at AMNH has reached more than 33,430,000 specimen and artifacts. From centuries-old specimens to entirely new types of specialized collections like frozen tissues and genomic data, the Museum’s scientific collections, form an irreplaceable record of life on Earth, the span of geologic time, and knowledge about our vast universe.

These specimens are the symbol of our Earths past life form. They are presently dead specimens of a vivid living past. They explain evolution of species (Darwin) and evolution due to catastrophism (Cuvier).

From centuries-old specimens to entirely new types of specialized collections like frozen tissues and genomic data, the Museum’s scientific collections (with more than 33,430,000 specimens and artifacts) form an irreplaceable record of life on Earth, the span of geologic time, and knowledge about our vast universe.

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Invertebrate fossils cover about 90 percent of the specimens. They include from gall wasps to ammonites. It’s not surprising that the largest Museum collection resides in the Division of Invertebrate Zoology.
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Paleontology

Dinosaurs are among the Museum’s biggest attractions—but the T. rex, the duck-billed mummy, and their prehistoric peers on the fourth floor are just a tiny fraction of the largest collection of dinosaurs in the world. The paleontology collection is also notable for its fossil mammals, the largest collection of its type in the world, and for its vast invertebrate holdings, which recently grew by about 540,000 marine fossils thanks to a donation of the Mapes collection by Ohio University.
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Vertebrate Zoology

Split among four departments—Ichthyology (fishes), Ornithology(birds), Mammalogy (mammals), and Herpetology (reptiles and amphibians)—the vertebrate collections house more than 3.5 million specimens that range in scale from tadpoles to ostriches, elephants, and whales. Among the species represented are such rare animals as coelacanths and extinct species including the dodo and Tasmanian wolf.

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Anthropology

More than half a million objects amassed over more than 140 years include significant archaeological collections from the Americas, including some of the oldest textile fragments found in the New World, as well as extensive ethnological collections from North America, Africa, Asia, and Oceania.

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Physical Sciences

Holdings in these collections range from volcanic rocks from Vesuvius tometeorites from Mars to minerals and gems that have been part of the Museum’s collection since its founding in 1869. Not included in the numbers below—but key resources for scientific research at the Museum—are the observations and simulations of the Museum’s astrophysicists.

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And above all,

Ambrose Monell Cryo Collection

There are shelves, there are jars, and then there are liquid nitrogen-cooled vats. That’s how the Museum’s Ambrose Monell Cryo Collection, which began operations in 2001, maintains frozen tissue specimens at temperatures below -150° Celsius. Since 2009, the AMCC  has also housed a special collection of tissues from endangered and threatened species for the United States National Park Service.

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The Shelf life is not just mystifying but also a residual form of life that existed in the past. This life was preserved in sediments for millions of years and now, AMNH takes them out and protects them in shelves. This collection helps scientists to study the past and to understand the complexity of life over millions of years.

The American Museum of Natural Museum has been doing a phenomenal work in collecting such large amount of samples. They have made a “Shelf Life” Series where new videos are uploaded every month with new interesting facts.

Links – http://www.amnh.org/shelf-life/shelf-life-33-million-things

http://www.amnh.org/shelf-life

Youtube Video – http://youtu.be/5NR-xl7W0vo

Amazing macro-photography of individual snowflakes [10 Pictures]

Photographer Alexey Kljatov takes incredible close-up photos of snowflakes in his backyard in Moscow.

“I capture snowflakes on the open balcony of my house, mostly on glass surface, lighted by an LED flashlight from the opposite side of the glass, and sometimes in natural light, using dark woolen fabrics as background.”

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http://twentytwowords.com

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