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Show Derald G. Smith, Richard A. Meyers, and Chris J. Simpson, Department of Geography, University of Calgary, Calgary, Alberta T2N 1N4, Canada Harry M. Jol, Department of Geography, University of Wisconsin- Eau Claire, WI 54702- 4004, U. S. A. Donald R. Currey, Department of Geography, University of Utah, Salt Lake City, UT 84112- 9155, U. S. A. DEPOSITIONAL SEQUENCE INFERRED FROM RADAR STRATIGRAPHY, LAKE BONNEVILLE BARRIER AND SPIT COMPLEX, STOCKTON BAR, UTAH Ground penetrating radar ( GPR) stratigraphic profiles of the classic Stockton Bar, Utah, cross- valley barrier and spit complex of late Pleistocene Lake Bonneville are used to infer a sequence of paleolake- culminating depositional events. We reconstruct the following depositional sequence on the basis of onlapping radar reflections of subsurface stratigraphy. ( 1) The southwest- trending cross- valley barrier formed at the mouth of Rush Valley by vertical accretion that kept pace with lake level rise. ( 2) A higher- elevation (+ 9 m) spit prograded 2 km southward into Rush Valley, depositing distal and lateral foresets. ( 3) A higher- elevation (+ 7 m) but shorter spit onlapped the proximal end of the 2- km- long spit, marking the Lake Bonneville highstand. |