USING STREAMS AS LINEAMENTS TO DELINEATE SUBSURFACE FRACTURE CHARACTERISTICS

Lineaments are mappable features on the surface that can reflect subsurface characteristics. They can be created by topography, soil cover, vegetation, and streams. Lineaments have been studied for exploration of both oil and water. Studies have shown that the use of lineaments can be a useful tool in both cases. Using streams as lineaments is a tool that has been under utilized. Streams are morphological features that are easy to detect but have not been fully utilized when analyzing subsurface fracture characteristics. Stream patterns have the potential to provide important insight to the effect of faulting on subsurface characteristics. Stream density, length, and orientation can be analyzed and compared with hydrologic and geophysical data to correctly determine if a correlation can be made.

The Arbuckle-Simpson aquifer in southern Oklahoma, which is heavily faulted, provides an ideal focus area for this research. With the help of GIS, nodes of each stream segment were obtained, creating over 60,000 data points over the Arbuckle-Simpson study area. The method allows a large number of data points used to observe these lineaments allowing for a detailed unbiased study. By obtaining lengths and orientations, trends can be observed in the stream patterns.

Results indicate that a quantitative correlation exists between faults, streams and subsurface characteristics. Using streams as lineaments will allow a delineation of subsurface characteristics and thus allow for a better understanding of the hydraulic properties of the aquifer. The results found will allow for a better quantification of the aquifer characteristics, which can be used as a management tool for the Arbuckle-Simpson aquifer. For future use, this method will provide a cost effective, unbiased, and rapid method to develop conceptual models in fractured aquifers.