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3-2 <br />~• 3.2 RESISTIVITY SOUNDINGS <br />~ Ertec personnel performed 49 vertical electric eoundinga to define <br />I stratigraphic relationships in the study area. <br />The eoundinga indicated Chat the geoelectrlc properties of the <br />area are extremely variable laterally. Apparent resiativitiea of less <br />~ than 1000 ohm-feet for layers beneath the topsoil indicate that the sandy <br />material is probably fine-grained and at least partially saturated. <br />~ Clay and shale layers were not specifically differentiated because of the <br />I <br />~ similarity in apparent reeistivities. <br />' The eoundinga were fairly definitive after geoelectcic models <br />were generated for each. There is a pronounced bedrock low in the plan[ <br />~ area trending south-southeast (Plate 2). The low area is interpreted as <br />the Ennis Draw paleo-channel. <br />Soundings did not definitively identify the narrow channel located <br />( • in the west central section of the study area. The lack of definition <br />~ may be due to the shallow or relatively impervious nature of the channel <br />~ fill. <br />The far western channel was defined by drill hole data and one <br />sounding. Further definition would be possible with seismic refraction <br />surveys or drilling. From the limited data we think that the western <br />channel ie fairly wide and shallow because of the low bedrock elopes <br />encountered west of the 4800-foot elevation contour line (Plate 2). <br />The reeistlvlty survey defined three channel areas; the Ennis <br />Draw paleo-channel, a narrow channel in the west-central portion of the <br />study area, and a wide channel along the far western boundary of the <br />study area. Further geophysical surveys combined vi [h auger or drill <br />hole information would better define the westernmost channel and the <br />feature found along line seven. <br />• <br />