CORRELATION OF POTENTIAL FIELDS AND GEOLOGIC DATA OF THE MISSISSIPPI EMBAYMENT

RABAK, I., LANGSTON, C. A., POWELL, C. A. Center for Earthquake Research and Information, University of Memphis, Memphis, TN 38152-3050, irabak@memphis.edu.

We correlate available potential field and geologic data for the Mississippi embayment to identify prominent features as viable scientific targets for future geophysical experiments. A set of potential field maps is generated using GMT and available USGS data sets. Numerous filters for image manipulation available through Adobe Photoshop are used for a preliminary analysis. The appropriate selection of a map color space is chosen not only to enhance already familiar anomalies of the region such as the Bloomfield pluton and the Missouri gravity low but also to highlight other, less obvious, gravity and magnetic anomalies. The Bloomfield pluton, judging by the gravity maps, together with other anomalies seems to be a part of a larger system of intrusions extending to the Gulf of Mexico. Several larger gravity anomalies, including the Bloomfield pluton, do have signatures on both maps of gravity and magnetic fields. However, this is not the usual case for all strong gravity and magnetic highs. Correlating the maps of the potential fields and geology, together with earthquake locations qualitatively reveals intriguing associations of inferred faults, seismicity, tomographic velocity anomalies, magnetic anomalies, and buried geological structure in the central part of the New Madrid Seismic Zone. This apparent complexity of crustal structure emphasizes the importance of proper visualization of geophysical/geological data sets in the Mississippi embayment.