Geostatistical Estimation of the Bottom Altitude and Thickness of the Mississippi River Valley Alluvial Aquifer

Scientific Investigations Map 3426
By:  and 



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 (

Suggested Citation

Torak, L.J., and Painter, J.A., 2019, Geostatistical estimation of the bottom altitude and thickness of the Mississippi River Valley alluvial aquifer: U.S. Geological Survey Scientific Investigations Map 3426, 2 sheets,

ISSN: 2329-132X (online)

Study Area

Table of Contents

  • Introduction
  • Data Compilation, Processing, and Filtering Prior to Estimation
  • Geostatistical Analytics
  • References
Publication type Report
Publication Subtype USGS Numbered Series
Title Geostatistical estimation of the bottom altitude and thickness of the Mississippi River Valley alluvial aquifer
Series title Scientific Investigations Map
Series number 3426
DOI 10.3133/sim3426
Year Published 2019
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Georgia Water Science Center, South Atlantic Water Science Center
Description 2 Plates: 28 x 34 inches; Data Release
Country United States
Online Only (Y/N) Y
Google Analytic Metrics Metrics page
Additional publication details