DOE Thermal Regimes Drilling Program through 1988
Article first published online: 3 JUN 2011
©1989. American Geophysical Union. All Rights Reserved.
Eos, Transactions American Geophysical Union
Volume 70, Issue 28, pages 697–707, 11 July 1989
How to Cite
1989), DOE Thermal Regimes Drilling Program through 1988, Eos Trans. AGU, 70(28), 697–707, doi:10.1029/89EO00215., , , , and (
- Issue published online: 3 JUN 2011
- Article first published online: 3 JUN 2011
To investigate the thermal, chemical, and mechanical behavior of magma during its ascent toward the surface, four holes were continuously cored into an igneous system young enough to be essentially unchanged since its emplacement. The system investigated was the 600-year-old Inyo chain of rhyolitic domes and flows in Long Valley, California (Figure 2). Three holes were drilled in or adjacent to Obsidian Dome at the north end of the chain, just outside the Long Valley caldera. One was drilled beneath the phreatic south Inyo Crater, at the south end of the chain in the west moat of the caldera.
The first hole was drilled in 1983 and penetrated the side of the lava dome, and continued into the underlying Tertiary basalt. The second hole, drilled in 1984, intersected and passed through the dome's vent and into Sierran granitic rock. The third hole, also drilled in 1984, sampled the rhyolitic feeder dike 1 km south of the dome's vent, where the magma did not reach the surface. The dike is part of the shallow dike system that underlies the Inyo chain.