Sentences with phrase «of mantle convection»

years (contingent on what we do), and the one after that, but at some point there could be some tectonic processes that make things more like the Cretacious — and there is probably some time horizon for the weather of mantle convection, too, while the climate of the mantle (layered vs whole vs mixed convection, general descriptions of cell sizes and rates of motion) may be predicted for longer time frames.

For this effort the observed history of plate tectonics could be imposed as velocity boundary conditions in dynamic calculations of mantle convection using a spherical geometry and realistic constitutive relations for geologic materials.

He calls this theory «top - down tectonics,» based on Kelvin's initial principles of mantle convection.

The answer to this question is very important for us to understand the nature of mantle convection,» explains lead author Mingming Li, who is pursuing his Ph.D. in geological sciences.

What we have done is to simulate the process of mantle convection by solving the equations which controls the process of mantle convection,» says Li.

«Based on our models of mantle convection, the mantle may be removing as much as half of Earth's total convective heat budget from the core,» Rowley said.

Not exact matches

Hotspots were thought to be caused by a narrow stream of hot mantle convecting up from the mantle - core boundary called a mantle plume, the latest geological evidence is pointing to upper - mantle convection as a cause.

«It gives us some insight into the connection between the slow circulation of near - solid rock in Earth's mantle caused by convection currents carrying heat upwards from the planet's interior, and observed active plate tectonics at the surface.

Another possible scenario is that small - scale convection is taking place within the channel as chunks of mantle cool and sink.

«These images will help us understand how convection connects Earth's surface with the bottom of the mantle,» said Associate Professor Tkalčić.

The plume's more southern location, Toomey said, adds fuel to his group's findings, at three different sites along the globe encircling mid-ocean ridge (where 85 percent of Earth's volcanic activity occurs), that Earth's internal convection doesn't always adhere to modeling efforts and raises new questions about how ocean plates at Earth's surface — the lithosphere — interact with the hotter, more fluid asthenosphere that sits atop the mantle.

«Learning about the anatomy of the mantle tells us more about how the deep interior of Earth works and what mechanisms are behind mantle convection,» said Nicholas Schmerr, an assistant professor of geology at UMD and co-author of the Science Advances paper that addresses mantle density and composition.

«There seems to be this critical filter and control on the movement of slabs and therefore convection of the mantle,» Klein says.

«This seems to suggest there was a big change going back in Earth's history in terms of how mantle convection and plate tectonic processes would have happened.»

Jagoutz says the results suggest that sometime between 3 billion years ago and today, as the Earth's interior cooled, the mantle switched from a one - layer convection system, in which slabs flowed freely from upper to lower layers of the mantle, to a two - layer configuration, where slabs had a harder time penetrating through to the lower mantle.

Meanwhile the MOLA data suggest that the elliptical northern hemisphere depression, some of the flattest terrain ever mapped, may have been an ancient seabed shaped by vigorous convection of the planet's mantle or tectonic plate recycling during the planet's formative stages.

Although the heat from impacts may not have been a limiting factor for life, asteroid bombardment introduced numerous other challenges, affecting the climate, surface or even convection of the mantle.

Convection, or the flow of mantle material transporting heat, drives plate tectonics.

It also was thought that planets were able to self - regulate their internal temperature via mantle convection — the underground shifting of rocks caused by internal heating and cooling.

Such diversity of size and internal temperature would not hamper planetary evolution if there was self - regulating mantle convection, Korenaga said.

Using Australia's National Computational Infrastructure's supercomputer Raijin, the team created high - resolution three - dimensional simulations of mantle evolution over the past 200 million years to understand the coupling between convection in the deep Earth and volcanism.

«The deflection of the plumes into these finger - like channels represents an intermediate scale of convection in the mantle, between the large - scale circulation that drives plate motions and the smaller scale plumes, which we are now starting to image.»

Through convection — slow movements of material in the upper mantle — the material was eventually mixed around and carried to the area of the mid-ocean ridges and transported back to the surface in the lavas that make up MORBs.

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.

This cooling and plate tectonics drives mantle convection, the cooling of the core, and Earth's magnetic field.

These ranged from global mantle - scale convection patterns, to the large thermochemical piles in the lower mantle, and down to the very small - scale pockets of ultra-low velocity zone at the bottom.

But this new study supports researchers» growing suspicion that mantle convection somehow regulates the amount of water in the oceans.

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

Now Yoshida and Madhava Santosh of Kochi University, Japan, have modelled how convection in the mantle — including the superplumes — will drive plate motion over the next 250 million years.

slow movement of Earth's solid mantle caused by convection currents transferring heat from the interior of the Earth to the surface.

The team calculated the balance between tidal heating and heat transport by convection in the mantles of each planet.

In contrast, super-Earths with a similar concentration but larger absolute amount of radioactive heat sources (i.e., uranium and thorium) than Earth would produce more internal heat, more vigorous mantle convection, and faster plate tectonic action involving thinner plates, which may promote planetary habitability with lower mountain ranges but higher volcanic activity and an atmosphere with a greater relative composition of volcanic and lighter gases (Sasselov and Valencia, Scientific American, August 2010; Valencia and O'Connell, 2009; and Valencia et al, 2007).

Scientists now recognize that macroscale behaviors, such as plate tectonics and mantle convection, arise from the microscale properties of Earth materials, including the smallest details of their atomic structures.

My first article on the subject (published Sep. 2009) refers to the convection in the underlying mantle (as reflected in changes of the area's magnetic intensity) is making significant contribution to the Atlantic basin climate change.

Convection of the mantle is expressed at the surface through the motions of tectonic plates.

The mantle is not quite solid and consists of magma which is in a state of semi-perpetual convection.

Kelvin modeled this as pure conduction, thinking of the mantle as too solid to admit convection.

Source and sink of heat, temperature at the start of the 10 billion years, mechanism of heat transfer through the mantle (conduction or convection?).

«The advent of plate tectonics made the classical mantle convection hypothesis even more untenable.

The evidence presented by Wegener and du Toit has been largely confirmed by global plate tectonics, and Holmes's causal account — mantle convection — is now generally accepted as the cause of plate tectonics.

Convection, or the flow of mantle material transporting heat, drives plate tectonics.