No abstract

The Albuquerque Basin of central New Mexico is about 102 mi long (north-south) and 25-40 mi wide (east-west). The Rio Grande, rising in Colorado and emptying into the Gulf of Mexico, flows southward through the basin which is surrounded by diverse Laramide and late Cenozoic uplifts. Several structural benches are delineated within the basin; fault scarps face the trough in most places. Ends of the basin are formed by convergence of side boundaries toward narrower structural and depositional channels that connect with basins north and south. The basin fill consists of up to 12,000 ft of sandstone, mudstone, and gravel of the Santa Fe Formation or Group (MiocenePliocene). In the northern part the fill is divided into the units of Bryan and McCann (1937) named in this report Zia, Middle red, and Ceja members. Elsewhere the fill generally is not divisible but may include equivalents of Zia and Ceja. Several facies of Santa Fe such as fanglomerates, playa, and river deposits and dunes are present. Late Pliocene deformation widened the basin, elevated the uplifts, and locally faulted and folded the Santa Fe. The deformation was followed by widespread pedimentation producing the Ortiz surface (probably early Pleistocene). Pleistocene and Holocene rejuvenation, deformation, and widespread dissection destroyed most of the surface. New correlations of Ortiz remnants are presented and the surface reconstructed. Numerous new faults are mapped and classified by relative ages, and several new folds and warpings of erosion surfaces are identified.

No abstract

No abstract