Sentences with phrase «mantle rock»

The heat apparently derives from a chemical reaction between mantle rock and seawater.

Some scientists have proposed mixing carbon dioxide (CO2) with water and injecting it into mantle rock as a means to fight climate change.

If just one percent of the weight of mantle rock located in the transition zone is H2O, that would be equivalent to nearly three times the amount of water in our oceans, the researchers said.

«New evidence for «oceans» of water deep in Earth: Water bound in mantle rock alters view of Earth's composition.»

Macquarie Island, which was named a World Heritage Site in 1997 (for being the only location in the world with mantle rocks actively exposed above sea level), has a long and difficult ecological history.

During the last ice age, a mile - high North American ice sheet, that stretched as far south as Long Island, N.Y., piled so much weight on the Earth that underlying mantle rock flowed slowly outward, away from the ice.

Their results pointed to less viscous, more free - flowing mantle rock above the megameter boundary, transitioning to highly viscous rock below the boundary.

Compression thickens not only the crust but also the cold, dense mantle rock immediately beneath.

During the last ice age, Greenland's ice sheet was much larger than now, and its enormous weight caused Greenland's crust to slowly sink into the softened mantle rock below.

They found that a mixture of normal mantle rock with 40 to 50 percent iron peroxide had the same seismic signature as the enigmatic ultralow velocity zones.

That's because the rising magma that produced the lavas probably mixed with upper mantle rocks, which have been contaminated with isotopically heavy surface water that got dragged down by subducting slabs of tectonic plates.

Now that West Antarctica is losing weight — that is, billions of tons of ice per year — its softer mantle rock is being nudged westward by the harder mantle beneath East Antarctica.

In 2012, he and his colleagues published a paper in Nature Geoscience that found compositional evidence for an impact within Procellarum — a type of pyroxene mineral that is found in other, known impact basins such as South Pole — Aitken and is associated with the melting or excavation of mantle rock from an asteroid impact.

From Northwestern University (h / t to Harold Ambler) Water bound in mantle rock alters our view of the Earth's composition Researchers from Northwestern University and the University of New Mexico report evidence for potentially oceans worth of water deep beneath the United States.

Hot mantle rocks, rebounding in the void like the splash of a stone in water, rose up into a central tower as high as 140 kilometers.

They then used the technique to analyze methane from Kidd Creek Mine, in Canada — one of the deepest accessible points on Earth — and two sites in California where the Earth's mantle rock reacts with groundwater.

Richards and Bunge suspected that the models were ignoring a key factor: the way that the viscosity, or stickiness, of the hot - mantle rocks changes with depth.

The study combined Jacobsen's lab experiments in which he studies mantle rock under the simulated high pressures of 400 miles below the Earth's surface with Schmandt's observations using vast amounts of seismic data from the USArray, a dense network of more than 2,000 seismometers across the United States.

The most conspicuous feature on Vesta is a giant impact crater located around its south polar region, which is 310 miles (499 kilometers) across and nearly 12 miles (19 km) deep around a «bull's - eye» central peak rising 11 miles (or 18 km) above the exposed mantle rock of the crater floor — that is characteristic of rock rebounding from an impact.

It is still rising, as mantle rock continues to flow inwards and upwards beneath Greenland.

Yellowstone, like the Hawaiian Islands, is believed to lie on top of one of the planet's few dozen hotspots where light hot molten mantle rock rises towards the surface.

The first evidence that ancient microbes colonised subsea mantle rock hints at how life might have emerged on Earth — and even other worlds

Now seismic imaging is also outlining two great globs of mantle rock standing beneath Africa and the Pacific like pistons.

That hot and dense mantle rock lies 3000 km below the surface, has steep sides, and is about 6000 km across, which is roughly the distance from New York to Paris.

But he adds, «If the ultra-low velocity pockets of rock have a composition different from the ordinary mantle rock, then mantle convection would continually carry them to the edges of piles where they collect.

Because there's no way to directly study deep mantle rocks, Panero and Pigott are probing the question with high - pressure physics experiments and computer calculations.

Earth's surface is clad in rigid rock plates — together called the lithosphere — formed of surface crustal rock laminated on to hard cold mantle rocks.

In a low temperature process called serpentinization, it transforms mantle rock such as the green periodotite into serpentinite, a rock with a dark scaly surface like a serpent's skin.

But a group led by geologist Rajdeep Dasgupta of Rice University in Texas put very small samples of peridotite under very large pressures and discovered mantle rock can and does liquefy, at least in small amounts, as deep as 150 miles (250 km) in the mantle.

Through experimentation on mantle rocks, Rice University researchers found evidence that magma forms much deeper than previously thought.

The redistribution of ice - water on the surface of the Earth and the flow of mantle rocks causes the gravitational field and the moment of inertia of the Earth to change.

This supports models where the material in the plume is a mixture of normal mantle rock and primordial rock from the dense rock anchoring the plume at the core - mantle boundary.

Senior author Barbara Romanowicz, a UC Berkeley professor of earth and planetary science, noted that the connections between the lower - mantle plumes and the volcanic hotspots are not direct because the tops of the plumes spread out like the delta of a river as they merge with the less viscous upper mantle rock.

The findings, to be published June 13 in the journal Science, will aid scientists in understanding how the Earth formed, what its current composition and inner workings are and how much water is trapped in mantle rock.

«The top of the core beneath this region is overlain by unusually hot and dense mantle rock,» said Tarduno.

One hint of weak coupling at a subduction zone is the presence of serpentinite — a mineral formed when seawater carried down by a descending plate reacts with mantle rock.

It was Green's laboratory that first conducted a serendipitous series of experiments, in 1989, on the right kind of mantle rocks that give geologists insight into how deep earthquakes work.

«Recent geophysical studies have suggested that the pattern changes because the mantle rocks flow less easily at that depth,» Shim said.

As slabs of Earth's crust decend into the mantle, they encounter a zone about 1,100 kilometers down where the mantle rock abruptly becomes stiffer, flowing less easily.

A stiffer crust, riding on top of the mantle rocks, cracked and settled to form the two outer rings.

The biggest difference being, that Mars has more iron in its mantle rocks, as the planet formed under marginally more oxidising conditions.»

Those variations can reveal different layers within the mantle, and can help scientists determine the temperature and chemistry of the mantle rocks by comparing observed variations in wave speed with predictions from other types of geophysical data.

According to a new study in the journal Science Advances, the hotspot softened the mantle rock beneath Greenland in a way that ultimately distorted their calculations for ice loss in the Greenland ice sheet.

The hotspot softened the rock in its wake, lowering the viscosity of the mantle rocks along a path running deep below the surface of Greenland's east coast.

In the mantle, heat comes both from radioactivity within the mantle rock and from the planet's core, the center of which is about as hot as Sun's surface.

Stray atoms of hydrogen could make up only a tiny fraction of mantle rock, the researchers explained.

The mantle exists because iron separated out from the mantle rocks, and then its much greater density caused it to sink to the center.

From there, the same convection of mantle rock that produces plate tectonics could carry the water to the surface.