A GEOPHYSICAL STUDY OF AN ANOMALOUSLY FLAT LANDFORM ALONG THE EASTERN FLANK OF THE WIND RIVER MOUNTAINS
This study focuses on the stratigraphy of the surface deposits and its contact with the underlying bedrock. Three resistivity surveys were conducted on 275 meter lines using a 5 meter interval with the AGI SuperSting RBIP provided by the Wy-CEHG. Line length and interval were chosen to obtain as deep a survey as possible. Survey sites were chosen based on their flat topography, and proximity to the middle of the mountain surface, where deep erosion is limited. Two surveys were run perpendicular near the center of the mountain surface, and another survey line ran near the Eastern flank of the mountain surface.
Results indicate layers of higher resistivity about thirty meters thick above a layer with lower resistivity values. East-West oriented survey lines reveal a fairly uniform, smooth contact between the layers. Perpendicular survey lines running North and South show a slight incline from South to North, about 5 m rise over 100 m.
The relatively smooth contact between unconsolidated surface deposits and the less resistive bedrock is consistent with glacial action. The relative uniformity of the top layer suggests only one event of deposition of this material. Future use of complementary geophysical methods should show the finer scale structure of the top layer.