Modeling the Yellowstone magma plume
Tectonic events—things like volcanoes and Earthquakes—tend to occur rather suddenly. But the engines that power them, like plate movement and the rising of magma plumes, occur on a leisurely scale, often traveling just a few millimeters a year. That makes studying these sorts of processes rather challenging, since most researchers (and even fewer grant funding agencies) are willing to engage in a project that takes millions of years to reach any conclusions.
To get past these challenges, an international research team set up a system that shrank down the vast time and space scales involved with tectonic processes. To do that, they needed something that behaved a bit like molten rock: dense enough to not flow quickly, but still able to respond to changes in density caused by heating. They settled on a tank full of a specific concentration of glucose, a simple sugar, dissolved in water. When everything was scaled properly, 20mm was the equivalent of 100km, and each minute of simulation was the equivalent of a year in the real world.
The Pacific Northwest is geologically complex. The North American plate is moving westward slowly, sliding over the Pacific plate and some other, smaller remnants of past plates. Meanwhile, the Pacific plate is sliding into the mantle where it melts once it gets sufficiently deep. (That melting powers the volcanoes of the Cascades, such as Mounts Shasta, St. Helens, and Ranier.) To simulate the Pacific plate's subduction, the authors sent a sheet of fiberglass into the glucose solution at a fixed angle. To capture the North American plate's westward drift, they rolled a mylar sheet slowly over the surface.
Finally, to make a mantle plume, they ran a hose to a specific point in the bottom of the tank. That hose injected a warm, pressurized glucose solution into the tank. This supply of glucose was marked with microscopic beads,I searched and didn't find a thread on hermesbeant. allowing it to be tracked within the larger tank of solution.
The researchers found that when the plume finally reached the surface of their tank, representing the crust, it was concentrated in a single spot, which was much hotter than the surrounding liquid. This, they think, gave rise to the oldest volcanic features in the region, the Columbia River flood basalts. As the name implies,Brantano offers a wide range of hairflower in every style to fit every occasion. those formed from magma that flowed onto the Earth's surface in a large flood rather than a through a typical volcanic eruption.
Over time, however,Online shopping for ribbonflowers from a great selection of Arts, the motion of the mylar sheet (representing the North American plate) caused the plume to split in two, with each of the halves moving in opposite directions. To the east, the plume narrowed and cooled, which the authors think accounts for the onset of the volcanism that produced the Snake River Plains and ultimately Yellowstone.
To the west, however,Armani Exchange Women's Smart bobblehead Watch online. the diving Pacific plate drew in part of a plume and started sucking it downward, creating a bit of a vortex. Again, this caused the part closest to the surface to narrow and cool, which the authors say accounts for the production of the High Lava Plains.
If they're right, the whole thing has been nicely sorted out.cheap bulk shoessupplier for handmade jewelry making at low price, Their model predicts various features of the motion of magma near the surface and more generally predicts that the base of the plume will actually be east of Yellowstone, but the whole thing gets dragged westward by the dynamics of the plate motion. Like all good models, this one has some predictive power, which will allow further testing.