USING GIS STREAM AND FAULT DATA TO EVALUATE AQUIFER ANISOTROPY IN THE ARBUCKLE-SIMPSON AQUIFER

Lineaments are mappable features on the surface that can reflect subsurface characteristics. They can be created by topography, soil cover, vegetation, streams, and faults. Stream and fault data collected using GIS, and outcrop data collected in the field were used as lineaments to assess anisotropy of the carbonate Arbuckle-Simpson aquifer in south-central Oklahoma. The advantage of using GIS layers of stream and fault locations to characterize subsurface aquifers is the amount of unbiased lineament data available. The results of this study indicate that a dominant 170o-0o trend exists over the study area as well as a less dominant 20-30o trend. The method used for the analysis allows for consistent orientation signals to become obvious even when there is little separation between signals. The results are somewhat unexpected as they are not parallel to the major faults in the area. An analysis of the effects of anisotropy in the dominant directions was performed to determine the effect on the size of spring basin areas in the aquifer.