Geophysics of Rio Grande Basins
Geologic Framework of Rio Grande Basins
Overall Project Objectives:
This project investigates the hydrogeologic framework along the course of the Rio Grande through New Mexico and Colorado to provide information on:
- critical ground-water aquifers
- seismic, subsidence, and landslide hazards
- minerals and energy resources
Mapping is integrated with studies of stratigraphy, biostratigraphy, magnetostratigraphy, and hydrogeologic characteristics of basin-fill sequences, and structural geology with emphasis on major faults and their effects on ground water. Geophysical mapping uses high-resolution aeromagnetic, gravity, and electromagnetic surveys to understand faulting and basin geometry.
Overall Project Relevance and Impact:
Basins of the Rio Grande encompass the main metropolitan areas of northern New Mexico—Santa Fe and Albuquerque—that are home of half the population and a significant part of the economy. In Colorado, the San Luis basin is the center of an extensive agricultural economy and host the Great Sand Dunes National Park and several Wildlife Refuges.
Linked by the through-flowing Rio Grande along the tectonic trough of the Rio Grande rift, the vitality of basin communities and economies depends on a growing supply of water extracted from complex aquifers, mostly in Santa Fe Group rift-basin sediments. Water withdrawals are regulated by New Mexico and Colorado State Engineers Offices to maintain the long-term utility of the aquifers, to satisfy regulatory and treaty commitments for in-stream flow of the Rio Grande, to avoid subsidence due to pumping, and to avoid low-quality or contaminated ground water. Knowledge of the aquifer systems and the linkages between recharge, ground-water flow, lithologic and stratigraphic characteristics, fault displacements, alteration/cementation, and productivity/sustainability of the resource are poorly known outside areas of production wells.
Overall Project Tasks:
- Española Basin
- Geophysical analysis and hydrogeology of faults
- San Luis Basin
An earlier task, now completed, focused on the Middle Rio Grande Basin.