Date of Graduation

12-2016

Document Type

Thesis

Degree Name

Master of Science in Geography (MS)

Degree Level

Graduate

Department

Geosciences

Advisor

Jason Tullis

Committee Member

William F. Limp

Second Committee Member

Jeral V. Skinner

Keywords

Social sciences; Earth sciences

Abstract

Groundwater depletion, a subject of growing concern for a significant portion of Arkansas, may lead to future economic challenges for the Arkansas Delta region. The Mississippi River Valley Alluvial Aquifer is the uppermost aquifer and features the largest groundwater capacity in the Mississippi Embayment Aquifer System. The Mississippi River Valley Alluvial Aquifer, commonly referred to as the “alluvial aquifer”, spans 53,000〖 km〗^2 underlying portions of Arkansas, Kentucky, Louisiana, Mississippi, Missouri, Illinois, and Tennessee. As the alluvial aquifer trends southward for approximately 250 miles alongside the Mississippi River, its geographical extent ranges from 50 to 125 miles wide. There is a considerable correlation associated with groundwater withdrawals level declines and the expansion of rice production, which was introduced to the Arkansas Grand Prairie in 1896 when W.H. Fuller returned from a hunting trip in Louisiana with rice seed. By 1916, the rate at which groundwater was being withdrawn already exceeded the natural recharge rate on the Grand Prairie. Mainstream GIS software provides a means for the modeling of groundwater levels through various spatial interpolation methods. Interpolation is the process of estimating unknown values in the form of a continuous surface, which utilizes observed values with known locations. With the growing concern of groundwater depletion in Arkansas, determining what is the most appropriate spatial interpolation method for producing accurate and reliable modeling of groundwater levels is essential. In addition, increased scrutiny on water resources is inevitable, and determining what is the most appropriate spatial interpolation method for producing accurate and reliable modeling of groundwater levels is essential. Based upon the results of two types of cross-validation for five separate years, ordinary kriging is the most appropriate interpolation method for generating groundwater level estimations for this particular study area. Simple kriging and empirical Bayesian kriging also provide suitable methods for producing groundwater level estimations for the Mississippi River Valley Alluvial Aquifer.