Sentences with phrase «deep mantle»

Over the course of time, this may have led to peaks in deep mantle melting and possibly to major volcanic events at the Earth's surface.

This crustal weakness allowed unusually high heat flow from deeper mantle sources to «super-heat» the highly organic Niobrara source rocks, which in turn generated the significant oil and gas deposits now contained in the Niobrara and Codell formations.

But releases of oxygen from upwelling of deep mantle FeO2 patches could provide an abiotic explanation for the phenomenon, they say.

They slow down the seismic waves caused by earthquakes and may be the culprit for deep mantle plumes, which can lead to volcanic hotspots like those that created Yellowstone National Park or the Hawai'ian Islands.

The Mid-Atlantic Ridge, particularly in the South Atlantic, also may have direct coupling with deep mantle flow, he added.

«This new constraint on plume structure has important implications for how deep mantle material is entrained in plumes, and it gives us the clearest picture yet for the chemical structure of an upwelling mantle plume.»

One of the major difficulties in testing the LIP — carbonatite link is the nature of the mantle source for the primary carbonatite melt: that is, whether the parental carbonatite magma was generated from the SCLM or from deep mantle sources.

Mineral physicists working in the lab will tease out more properties of rock under deep mantle conditions to inform interpretation of the seismic data, although still handicapped by the uncertain details of mantle composition.

«We see strong support for significant deep mantle contributions of heat - to - plate dynamics in the Pacific hemisphere,» said Rowley, lead author of the paper.

«CT scan of Earth links deep mantle plumes with volcanic hotspots: Scans prove that plumes of hot rock anchored at core - mantle boundary rise to form island chains.»

Known as cratons, these masses have deep mantle roots that can reach down some 200 kilometers below the surface.

«If true,» he says, «this will be very important in how we think about the links between surface plate motions and deep mantle convection.»

«Earth's dynamic interior: Multiple compositional components of Earth's deep mantle carried up to surface.»

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.

«For the scientists who do not believe hot spots like Réunion are due to deep mantle plumes, this should be a challenge.»

An ancient eruption, like the recent Holuhraun eruption in Iceland, brought up deep mantle material that contains clues about the origin of Earth's water.

In geosciences a «hotspot» refers to a phenomenon of columnar shaped streams, which transport hot material from the deep mantle to the surface.

Scientists studying volcanic hotspots have strong evidence of this, finding high helium - 3 relative to helium - 4 in some plumes, the upwellings from Earth's deep mantle.

«We used the seismology of the shallow mantle — the rate at which seismic waves travel through Earth below its crust — to make inferences about the deeper mantle,» said Jackson, an assistant professor in UCSB's Department of Earth Science.

Ice - VII inclusions in diamonds: Evidence for aqueous fluid in Earth's deep mantle.

Researchers have suspected that abundant aqueous fluid exists in the deep mantle, ferried there by slabs bearing water - rich minerals that shed their water when they reach the transition zone (SN: 7/12/14, p. 9).

So the researchers took the same chemistry as found in enstatite chondrites, and began to subject them to the sort of pressures and temperatures found in the deep mantle of Mercury.

The Hawaii research relies on a new seismic technique for detecting aligned flows of rock that has yet to be verified, says marine geophysicist Cecily Wolfe of the Woods Hole Oceanographic Institution in Massachusetts and the Carnegie Institution of Washington, D.C.. However, the Iceland study is «very clear and compelling,» she says, and consistent with a deep mantle origin for the plume.

«In the Earth's deep mantle, we should find iron in its less oxidized form, known as ferrous iron, or in its metal form.

This is stretched over time by the supply of hot material from the deep mantle.

«The deep mantle is a weird place with mysterious features that may be residues of Earth's formation, graveyards for piles of sunken tectonic plates, sources for hotspot volcanoes like Hawaii or the processes that shaped the atmosphere,» Dorfman said.

Form the mid Cretaceous onwards the subduction zone was deep enough to induce large - scale flow in the deep mantle, down to 2900 km, the boundary between the Earth's mantle and core.

Inclusions like these, providing samples of metal from Earth's deep mantle, have not been recognized before.»

The found that 3He to 22Ne ratio from the shallow mantle is significantly higher than the equivalent ratio in the deep mantle.

It is known that material brought to the surface from the deep mantle (via mantle plumes) has a lower ratio than that normally found nearer the surface, for example in the basalts from mid-ocean ridges.

«So when these continents started opening up and the deeper mantle was exposed, more or less, to the atmosphere and the ocean it started cooling much faster.»

Using this model, Liu, along with doctoral student Jiashun Hu, and Manuele Faccenda from the University of Padua in Italy, recently published a research paper in the journal of Earth and Planetary Science Letters that focuses on the deep mantle and its relationship to plate tectonics.

Over Earth's lifespan or «geological time» the largely solid mantle has continuously been stirred by old, cold tectonic plate sections sinking into the deep mantle, under another plate.

With a combined surface area exceeding 2 million square kilometres, both basins are located directly above the deep mantle slab.

Based on measurements of Jupiter and the solar wind, which are thought to preserve the hydrogen isotopic ratio of the protosolar nebula, scientists think nebular water had an extremely light hydrogen isotopic signature — much closer to what the Baffin Island lavas suggest about the deep mantle's water.

«The East Pacific Rise is stable because the flow arising from the deep mantle has captured it,» Rowley said.

The deep mantle - derived buoyancy, together with plate cooling at the surface, creates negative buoyancy that together explain the observations along the East Pacific Rise and surrounding Pacific subduction zones.

«These findings suggest the shape of volcanic seamount chains record motion in the deepest mantle, near the Earth's core.

The new research shows the shapes of these piles have changed through time and their shapes can be strongly dependent on rapid, coherent flow in the deep mantle.

One of the most contentious debates in geoscience has centred on whether piles of rock in the deep mantle — to which plumes are anchored — have remained stationary, unaffected by mantle flow over hundreds of millions of years.

«Because rock in the deep mantle moves less than a centimeter a year, we know the LLSVP is ancient, meaning it may be a longstanding site for the loss of magnetic field strength,» said Tarduno.

«We had an intuition that, since the north Pacific experienced a prolonged phase where large, cold tectonic plates uninterruptedly sank into the mantle, the flow in the deepest mantle there would be very different compared to other regions of the Earth,» Mr Hassan said.

Observations, modeling and predictions have indicated that the deepest mantle is compositionally complex and continuously churning and changing.

The discovery of Ice - VII in the diamonds is the first known natural occurrence of the aqueous fluid from the deep mantle.

Geoscientists have thought the zones are partially molten, yet the pockets are puzzling because many are observed in cooler regions of the deep mantle.

«You can have various mechanisms, such as plate tectonics, that push rock of differing chemistries into the deepest mantle anywhere on Earth,» he says.

It is commonly assumed that enormous masses of magma ascended from the deep mantle up to higher levels, and that this hot mantle plume (the Tristan mantle plume) weakened the continental lithosphere, eventually causing the break - up of the continental plate of Gondwana.

Using laboratory techniques to mimic the conditions found deep inside Earth, a team of Carnegie scientists led by Ho - Kwang «Dave» Mao has identified a form of iron oxide that they believe could explain seismic and geothermal signatures in the deep mantle.