Scientific Drilling at Sulphur Springs, Valles Caldera, New Mexico: Core Hole VC 2A
Article first published online: 3 JUN 2011
©1987. American Geophysical Union. All Rights Reserved.
Eos, Transactions American Geophysical Union
Volume 68, Issue 30, pages 649–662, 28 July 1987
How to Cite
1987), Scientific Drilling at Sulphur Springs, Valles Caldera, New Mexico: Core Hole VC 2A, Eos Trans. AGU, 68(30), 649–662, doi:10.1029/EO068i030p00649-01., , , , , , and (
- Issue published online: 3 JUN 2011
- Article first published online: 3 JUN 2011
A scientific core hole has been drilled into the western ring fracture zone of the Valles Caldera, N.Mex. Hole VC-2A, the second scientific core hole in the caldera, was cored through a faulted and brecciated sequence of intracaldera tuffs and volcaniclastic rocks to a depth of 528 m at Sulphur Springs. As of November 1, 1986, the unequilibrated bottom hole temperature was 212°C. The rocks that have been penetrated are intensely altered and contain molybdenite mineralization (MnC>2) that is less than or equal to 1.1 m.y. in age. The active hydrothermal system at Sulphur Springs consists of a thin (5-m) acid condensation zone overlying vapor- and water-dominated zones. The latter two zones are apparently separated by a region of tightly sealed rock.