Wednesday, April 2, 2008 : 3:00 p.m.

Detailed hydrostratigraphy of the Wilcox and Claiborne Group in northeastern Arkansas, northwestern Mississippi, and western Tennessee

Daniel Larsen, Ph.D., Kasey Hundt, Brian Waldron, Ph.D., Roy Van Arsdale, Ph.D., David N. Lumsden and Ryan Csontos, University of Memphis

Detailed lithostratigraphic correlation of Paleocene through Eocene Wilcox and Claiborne Group strata in the tri-state region of Arkansas, Mississippi, and Tennessee has been conducted to better assess hydrostratigraphic relationships and provide a working framework for sub-regional-scale ground-water flow modeling.  Although lithostratigraphic correlations have been made at the regional scale in the past, our study aims to evaluate aquifer compartmentalization and connectivity on local to semi-regional scales, focusing on both formation- and intraformation-scale correlation.  The Wilcox and Claiborne groups comprise sand, silt, clay, and lignite sediments in the northern Mississippi Embayment, which are readily amenable to geophysical log correlation.  Geophysical and lithologic log data were collected from well libraries at the United States Geological Survey, Arkansas Soil and Water Division, private drilling contractors, and the Ground Water Institute.  One southwest-northeast trending cross-section was constructed along the axis of the Embayment as well as six southeast-northwest-trending cross-sections.  Geologic formation and intraformation units defined in the cross-sections were used to interpret geophysical logs in intervening areas.  The results indicate a gradual thickening and fining of strata toward the axis of the embayment and down structural dip to the south.  Fine-grained stratigraphic units identified in down-dip (Mississippi) logs commonly become thinner or intermittent in their distribution in up-dip (northeastern Arkansas and northwestern Tennessee) logs.  Structural offsets of strata are generally minimal and mainly associated with the SW-NE structural grain of the basin.  Although regional continuity of most recognized aquifers is observed, internal partitioning increases toward the center of the Mississippi Embayment.  Furthermore, sandy incised valley-fill deposits with regional confining units are observed toward the eastern margin of the embayment and provide potential avenues for water transfer between the successive aquifers.

Daniel Larsen, Ph.D., University of Memphis I have investigated low-temperature geochemistry and hydrogeology for over 20 years. After completing my Ph.D. in 1994 at the University of New Mexico with emphasis in sedimentology and low-temperature geochemistry and a short stint as a geochemical modeler with Jacobs Engineering, I took a faculty position at the University of Memphis in 1995. Since that time, I have taught courses in environmental geology, geochemistry, sedimentology, and hydrogeology with emphasis on field studies. My research interests have been mainly in stratigraphic controls on hydrologic and geochemical processes, ground-water tracing, and regional Cenozoic stratigraphy.

Kasey Hundt, University of Memphis Graduate Assistant, Dept. of Earth Sciences, The University of Memphis, Memphis, TN 38152, Tel: 901-678-4355 Email: khundt@memphis.edu. Mr. Hundt is graduate student at the University of Memphis and is currently pursuing a Master Degree in Earth Sciences. The emphasis of his studies is in stratigraphy and hydrogeology.

Brian Waldron, Ph.D., University of Memphis Assistant Professor, Ground Water Institute, The University of Memphis, 301 Engineering Admin. Bldg., Memphis, TN 38152, Tel: 901-678-3913 Email: bwaldron@memphis.edu. Dr. Waldron has been Associate Director for the Ground Water Institute for 7 years and specializes in ground-water engineering, ground-water flow modeling, and GIS. He has initiated several major studies of ground-water resources in the Memphis area.

Roy Van Arsdale, Ph.D., University of Memphis Professor, Dept. of Earth Sciences, The University of Memphis, Memphis, TN 38152, Tel: 901-678-4356 Email: rvanrsdl@memphis.edu. Dr. Van Arsdale has been a faculty member at the University of Memphis for 15 years and specializes in neotectonics, geomorphology, and structural geology. He has published extensively on the New Madrid Seismic Zone, the origin of the Mississippi Embayment, and earthquake hazards in intraplate tectonic settings.

David N. Lumsden, University of Memphis Professor, Dept. of Earth Sciences, The University of Memphis, Memphis, TN 38152, Tel: 901-678-4359 Email: dlumsden@memphis.edu. Dr. Lumsden has been a faculty member at the University of Memphis for 40 years and specializes in sedimentology and stratigraphy. Dr. Lumsden has published extensively on the stratigraphy and sedimentology of central and western Tennessee, and the origin of sedimentary dolomite.

Ryan Csontos, University of Memphis Post-doctoral Associate, Ground Water Institute, The University of Memphis, 300 Engineering Admin. Bldg., Memphis, TN 38152, Tel: 901-678-4315 Email: rcsontos@memphis.edu. Dr. Csontos received his Ph.D. in 2007 from the University of Memphis, Department of Earth Sciences, on the structure and evolution of New Madrid Seismic Zone. His expertise is in three-dimensional modeling and structure of the crust and GIS.


2008 Ground Water Summit