The Mississippi River Valley alluvial aquifer (MRVA) caps a shallow system of aquifers and confining units in the Mississippi Alluvial Plain (MAP) that extends across 45,000 square miles of the midwestern and southern United States from Illinois to Louisiana. Irrigation water from the MRVA is required to sustain extensive crop production, which has resulted in groundwater-level declines since the late 1920s equal to nearly half of its thickness and in reduced baseflow of streams. Increased groundwater withdrawal for irrigation is expected to continue and threatens complete and irreversible aquifer dewatering (depletion). The exact amount of dewatering in the MRVA is uncertain because its vertical extent is poorly defined and the effects of groundwater withdrawal on the aquifer are not well understood. To provide stakeholders and managers with information and tools that promote understanding of the hydrogeologic framework of the MAP extent and its role in water-resource management, the U.S. Geological Survey (USGS) Water Availability and Use Science Program has funded a 5-year effort to assess groundwater availability and project future sustainability of water resources. Part of this study involves mapping the bottom altitude and thickness of the aquifer by using compilations of hydrogeologic data and applications of geostatistical analytics. Results of this mapping effort, presented here, are intended to enhance characterization of the shallow hydrogeologic framework and direct future airborne, ground-based, and waterborne geophysical surveys. Data used in support of the findings presented in this report are available as a USGS data release (https://doi.org/10.5066/P9D9XR5F).
Citation Information
Publication Year | 2019 |
---|---|
Title | Geostatistical estimation of the bottom altitude and thickness of the Mississippi River Valley alluvial aquifer |
DOI | 10.3133/sim3426 |
Authors | Lynn J. Torak, Jaime A. Painter |
Publication Type | Report |
Publication Subtype | USGS Numbered Series |
Series Title | Scientific Investigations Map |
Series Number | 3426 |
Index ID | sim3426 |
Record Source | USGS Publications Warehouse |
USGS Organization | Georgia Water Science Center; South Atlantic Water Science Center |
Related Content
Digital surfaces of the bottom altitude and thickness of the Mississippi River Valley alluvial aquifer and site data within the Mississippi Alluvial Plain project region
Related Content
- Data
Digital surfaces of the bottom altitude and thickness of the Mississippi River Valley alluvial aquifer and site data within the Mississippi Alluvial Plain project region
Bottom altitudes of the Mississippi River Valley alluvial aquifer (MRVA) were compiled from interpretations of subsurface geophysical logs (log picks) at about 10,000 boreholes and wells located throughout the Mississippi Alluvial Plain (MAP) that were available from previous investigations. Five sources of the bottom altitude data are listed numerically in the Cross Reference section (below) and - Connect