AN INTEGRATED ANALYSIS OF THE JORNADA DEL MUERTO BASIN IN SOUTH-CENTRAL NEW MEXICO UTILIZING REMOTE SENSING AND GEOPHYSICAL METHODS

Continental rifts are large-scale structural features that are expressed in the form of fault systems that are present where the lithosphere has fractured due to crustal extension. The Rio Grande rift is the result of this type of extension of continental crust. The Rio Grande rift is a lithospheric-scale feature that follows the topographic crest of a broad topographic high that includes the southern Rocky Mountains. The basins and ranges, which formed due to the Rio Grande rift, are valuable localities for resources ranging from groundwater to minerals. Since being recognized as an important continental rift in the 1970's this feature has been the object of considerable interest and study by geologists and geophysicists around the world. The northern portion of this feature forms a classic physiographic rift valley and structurally consists of a series of interconnected, asymetrical grabens extending from leadville, Colorado to Socorro, New Mexico. South of Socorro, the rift widens into at least two major parallel rift structures. These two structures flank the Jornada del Muerto basin. There has been much uncertainty about the structural setting of the Jornada del Muerto basin. Utilizing Landsat images, USGS DEM's, and digitized regional geological maps the impression that the basin is underlain by a syncline is evident by the dipping of the strata in the mountain ranges bounding the basin dipping toward one another. When gravity anomalies are overlaid a complex basinal structure with deep sub-basins being located at the southern and northern ends of the Jornada del Muerto basin is revealed. Seismic and drilling data are available in the southern portion of the basin and reveal that both Laramide and rift tectonics contributed to the formation of the Jornada del Muerto.