The Yellowstone caldera, in the western United States, formed ???640,000 years ago when an explosive eruption ejected ???1,000 km3 of material. It is the youngest of a series of large calderas that formed during sequential cataclysmic eruptions that began ???16 million years ago in eastern Oregon and northern Nevada. The Yellowstone caldera was largely buried by rhyolite lava flows during eruptions that occurred from ???150,000 to ???70,000 years ago. Since the last eruption, Yellowstone has remained restless, with high seismicity, continuing uplift/subsidence episodes with movements of ???70 cm historically to several metres since the Pleistocene epoch, and intense hydrothermal activity. Here we present observations of a new mode of surface deformation in Yellowstone, based on radar interferometry observations from the European Space Agency ERS-2 satellite. We infer that the observed pattern of uplift and subsidence results from variations in the movement of molten basalt into and out of the Yellowstone volcanic system. ?? 2006 Nature Publishing Group.
Additional Publication Details
Uplift, thermal unrest and magma intrusion at Yellowstone caldera