New Mexico Geological Society Annual Spring Meeting — Abstracts

High precision temperature logs, made in a number of wells located on the southern part of Sandia National Laboratories/Kirtland Air Force Base, hopefully provide a glimpse of the ground-water flow patterns in this boundary area of an intermontane basin. The study area borders the Albuquerque Basin Rio Grande rift located to the west and the Manzanito Mountains located to the east. The hydrogeology of the area depends on variations of hydraulic conductivity in the sediments as well as variations in the hydraulic properties of numerous faults in the area. The first order hydrogeologic observation in the region is the steep drop in ground-water elevation associated with the Sandia and/or Tijeras faults . The temperature data are organized along three west to east profiles in an attempt to observe the nature of ground-water flow in the area. Data along the southern profile, at the boundary with Iselta Pueblo, suggest the Sandia Fault is non-transmissive over shallow depths. The data along a profile ~1 km to the north indicate flow across the Sandia Fault; the location is near the intersection with several other faults. The data also suggest the flow occurs over a rather thin channel in the sediments, causing flow at the fault to be near or below the water table on the downthrown block. Data along a third, northern profile are insufficient to relate to flow across the fault complex, however, low temperature gradients do suggest channel flow associated with the Tijeras and Coyote arroyos. These data suggest the ground-water flow in the area is quite variable, both geographically and vertically. If the data are correctly interpreted, models of ground-water flow should incorporate the probable variability in hydraulic conductivity.