Seafloor Mountain Expedition Studied Crust's Deepest Layer

A topographical map of the Atlantis Massif, which also shows the location of its Lost City hydrothermal vents.

CREDIT: NOAA.

Scientists recently returned from an expedition to an unusual seafloor mountain, where they conducted what may be the first-ever on-site study of a type of rock that makes up a huge amount of our planet, but is largely out of reach.

Researchers aboard the research vessel JOIDES Resolution sent instruments to the Atlantis Massif, a seamount that lies near the Mid-Atlantic Ridge, a long volcanic rift bisecting the Atlantic Ocean, where two tectonic plates are being slowly shoved apart and fresh oceanic crust is created.

Seamounts are essentially a mountain that doesn't rise above the ocean's surface.

Unlike most seamounts, which are typically made of volcanic rock, geological forces essentially yanked the Atlantis Massif from the Earth's gabbroic layer — the deepest layer of the Earth's crust, which rests directly on the planet's ever-shifting mantle.

Semisopochnoi Island: Volcano Mt Cerberus

Far to SW of Alaska lies Semisopochnoi Island in the Rat island group West Aleutians; foreground volcano Mt Cerberus.

It is the “Island of the Seven Mountains, ” or more precisely in Russian: “having seven hills.”

This uninhabited volcanic island is also an important nesting area for maritime birds of the North Pacific.

Situated on the far end of the Aleutians, Semisopochnoi Island is simultaneously the most easterly and westerly point of the United States of America.

Roughly 1,275 miles (2,050 kilometers) west-southwest of Anchorage, Alaska, Semisopochnoi lies near the 180-degree line of longitude, in the Rat Islands group in the western Aleutian Islands.

The seven hills of the island are volcanic peaks, each with a summit crater, including Cerberus, Sugarloaf Peak, Lakeshore Cone, Anvil Peak, Pochnoi, Ragged Top, and Three-quarter Cone.

The high point of the island is Anvil Peak at 1,221 meters, a double-peaked cone. The three-peaked Mount Cerberus volcano (774 meters high) grew up within the caldera as the volcanic hot spot rose up from the sea floor.

Most documented eruptions have come from Cerberus, with the most recent major eruption recorded in 1873. The most recent eruption on the island, though minor, came from Sugarloaf in 1987.

Semisopochnoi has no native land mammals, so it is a natural nesting area for sea birds but bird populations were decimated after Arctic foxes were introduced to the island for fur farming in the 19th century.

In 1997, the last fox was removed from the island to allow the birds a safe refuge again. Part of the Alaska Maritime National Wildlife Refuge (AMNWR), the island now supports more than a million seabirds, particularly auklets, according to the National Audubon Society.

ESA Live Online Videos: Snow Mountains

Earth from Space is presented by Kelsea Brennan-Wessels from the ESA Web-TV virtual studios. 

In the tenth edition we look at the snow-kissed Alps, Italy’s Apennines and point out some major lakes.

Click on the Image to visit the ESA site and play the Live video.

ESA Astronaut Image: Mountain 'Veins' in the Somalian desert

'Veins' in the Somalian desert

Credit: ESA/NASA

UFO Cloud over the Crazy Mountains

A lenticular cloud, also called a UFO cloud, forms over the Crazy Mountains in Montana, USA

Picture: James Woodcock, Billings Gazette/AP

ESA Mars Express: Mountains and buried ice

Phlegra Montes is a range of gently curving mountains and ridges on Mars.

They extend from the northeastern portion of the Elysium volcanic province to the northern lowlands.

This image is centred at 33°N/162°E. The High-Resolution Stereo Camera (HRSC) on ESA’s Mars Express collected the data for these images on 1 June 2011 during orbit 9465. The images have a ground resolution of about 16 m per pixel.

Credits: ESA/DLR/FU Berlin (G. Neukum)

A wider contextual image of the region surrounding Phlegra Montes. The smaller rectangle shows the region covered in this Mars Express HRSC image release.

Credits: NASA MGS MOLA Science Team

Read more on this story at ESA Portal

BAS Fly-through of Antarctica's Gamburtsev 'ghost mountains'

Click on the Image to visit BBC website and activate the Animation.

Scientists think they can now explain the existence of what are perhaps Earth's most extraordinary mountains.

The Gamburtsevs are the size of the European Alps and yet are totally buried beneath the Antarctic ice.

A geophysical survey of the range was conducted in 2008/9. This allowed researchers to assess the mountains' origin.

In this video, Fausto Ferraccioli from the British Antarctic Survey takes us on a virtual fly-through of the Gamburtsevs.

Animation courtesy of the British Antarctic Survey.

Crown of the Dolomites

"The Crown of the Dolomites", a composite image of 14 pictures showing the Milky Way over the Dolomite Mountains in northern Italy, captured by Italian photographer and engineering student, Edoardo Brotto...

Picture: Edoardo Brotto / Barcroft Media

THE birth of the US Appalachian mountain chain caused mass extinction

THE birth of the US Appalachian mountain chain may have been behind a major ice age and a mass extinction.

The extinction event at the end of the Ordovician 450 million years ago was the second largest Earth has ever seen. It has long been believed that an ice age caused it, but no one knew what triggered the freeze.

Seth Young of Indiana University in Bloomington, and colleagues, believe two factors conspired to create the deep freeze. First, layers of lava show that climate-warming volcanic activity slowed down at this time. The second factor was an increase in the weathering of the Appalachian rocks between 462 and 454 million years ago, which is indicated by changes in strontium isotope ratios in Ordovician oceanic rocks (Geology, DOI: 10.1130/g30152a.1).