Rio Grande Rift – Tectonics and Magmatism

Published by the American Geophysical Union as part of the Special Publications Series.

The Rio Grande rift was largely overlooked as a major continental rift until the 1970's. Geologists in the United States were preoccupied with the much larger Basin and Range province and with the southern Rocky Mountains. The pioneering studies of Bryan (1938) and Kelley (1952, 1954, 1956) had appeared in regional publications that were generally not known outside the southwestern United States. During the 1960's, the Rio Grande rift appeared on maps in several regional studies (Eardley, 1962; Hamilton and Myers, 1966; Cook, 1969) and was variously termed the Rio Grande "rift valley system", "rift belt", or "depression". Many geologists regarded the Rio Grande rift as merely a prong of the Basin and Range province. However, the paper by Seager and Morgan in this volume presents evidence that the southern Rio Grande rift differs from the adjacent Basin and Range province in several important aspects.