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yellowstone caldera to blow soon real soon-your life will change forever
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Original Message
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12 hours ago
... activity of the caldera from those that presage a forthcoming eruption...
get ready to cahnge your life forgot about debt, jobs
it will be survival only
good luck chumps...
over 500 Earthquakes at Yellowstone in
the last week
18 earthquakes on January 2, 2009
12 earthquakes on January 1, 2009
58 earthquakes on December 31, 2008
23 Earthquakes on December 30, 2008
38 Earthquakes on December 29, 2008
103 Earthquakes on December 28, 2008
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The Caldera Today
Is Yellowstone's history of volcanic activity at an end? Has time tamed its explosive violence, leaving only a heritage of aging geysers and eroding lava flows? Has the magma chamber beneath Yellowstone exhausted its supply of molten rock? Is it now incapable of producing more lava flows or explosions? Well, let's consider these questions; questions that have intrigued scientists ever since Yellowstone was discovered.
Anyone who has seen a geyser or hot spring immediately thinks of heat. Early geologists speculated that the heat in geyser waters came from the cooling of young lava flows beneath the geyser basins. They speculated that rain and snow meltwater percolated into gravels and sands of the basins and into the young lava flows where it was heated before rising to the surface via geysers and hot springs. The lava flows were thought to be young, but even the most daring geologist tucked them well back in time. As we learned in Chapter 4, however, U. S. Geological Survey studies that dated the lava flows found some of them to be rather young, indeed.
Given that the youngest lava flows are only 70,000 years old, yesterday in geologic time, might not there still be molten magma beneath Yellowstone today? Direct methods, such as deep drilling, have not been employed to test this possibility, but other methods suggest magma exists beneath Yellowstone.
The earth's interior is warmer than its surface causing heat flow outward to the surface. The flow of heat in geyser basins is hundreds of times greater than normal heat flows. If the total conductive heat flow of major hydrothermal basins is averaged over the 965 sq. miles of the Yellowstone Caldera, we find flow levels that are 60 times greater than mean global rates.
Geophysical studies monitor the caldera and its magma body indirectly. From seismic studies we learn that shock waves from earthquakes and man-caused explosions traveling through the earth's crust are slowed significantly as they pass beneath the caldera. Material with a seismic velocity that is slower than normal underlies the caldera at depths as shallow as I mile. This may indicate local zones of molten magma in the upper crust. Near the northeast part of the caldera, seismic velocities are even lower to within about 2 miles of the surface; this may indicate a more continuous magma body that extends from the northeastern part of the caldera to about 10 miles beyond it. Down below the crust and in the mantle at depths of 100 miles, lower than normal local seismic velocities may indicate thin rising columns of magma.
Earthquake data also suggest that soft or molten rock is close to the surface of Yellowstone. Minor earthquakes jiggle Yellowstone hundreds of times each year, the caldera the foci of these quakes are extremely shallow, less than three miles below the surface. These clues suggest that the material underlying Yellowstone is still very hot and ductile, as would be expected if a magma chamber still exists.
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