Delineating the Rattlesnake Springs, New Mexico Watershed using Near-Surface Geophysical Techniques

We used a combination of ground conductivity, DC resistivity and precision gravity surveys in an effort to characterize the watershed of Rattlesnake Springs, New Mexico. The Springs serve as the domestic water source for Carlsbad Caverns National Park. Our results confirm previous geological studies that suggested ground water flows into the Springs from a number of sources. Gravity, resistivity and conductivity studies indicate that fine grained clays, possibly related to a collapsed karst feature, located to the north and northwest of the Springs serve as a barrier to fluid flow and may be responsible for the Springs' current location. Gravity data also suggest that north-south and west-northwest oriented fractures within the underlying gypsum bedrock serve as conduits to funnel ground water from the south and southwest. These fracture directions are consistent with fracture systems observed to the north within the limestone of the Guadalupe Escarpment, suggesting the fracture system resulted from regional tectonism.