Geographic Extent and Shape of an Extensive Magma Body at Mid-Crustal Depths in the Rio Grande Rift Near Socorro, New Mexico.
- Robert E. Riecker
Published Online: 21 MAR 2013
Copyright © 1979 by the American Geophysical Union.
Rio Grande Rift: Tectonics and Magmatism
How to Cite
Rinehart, E. J., Sanford, A. R. and Ward, R. M. (1979) Geographic Extent and Shape of an Extensive Magma Body at Mid-Crustal Depths in the Rio Grande Rift Near Socorro, New Mexico., in Rio Grande Rift: Tectonics and Magmatism (ed R. E. Riecker), American Geophysical Union, Washington, D. C.. doi: 10.1029/SP014p0237
- Published Online: 21 MAR 2013
- Published Print: 1 JAN 1979
Print ISBN: 9780875902142
Online ISBN: 9781118664988
- Extensive magma body;
- Geodetic measurements;
- Geologic and geophysical characteristics;
- Surface relief
Depth, geographic extent, and relief on a mid-crustal magma layer in the Rio Grande rift near Socorro were determined from 220 accurately located S-wave reflection points obtained from a microearthquake study. Important additional controls on the configuration of the magma body were obtained from COCORP P-wave reflection data. As presently mapped, the magma occurs as a thin flat sill at depths of 19 to 20 km beneath 1700 km2 of the central part of the rift. Geodetic data in the Socorro area indicate horizontal compressive strain over the region and thus magma bodies of this configuration are possible. A control on the placement of the sill could be a resistive rock layer immediately above the Conrad discontinuity. An unusual feature of the magma layer is its lack of relief beneath surface structures with large vertical displacements. This may indicate possible detachment of the brittle uppermost crust from a plastic zone at lower levels.