HR: 0803h
AN: NS11D-0794    [Abstracts]
TI: Seismic Refraction Mapping of the K-T Boundary Complex Near the Brazos River, Falls County, Texas
AU: * Gowan, J S
EM: gowan-underscore-josh@hotmail.com
AF: Dept of Geology and Geophysics, Texas A&M University, College Station, TX 77843, United States
AU: Everett, M E
EM: everett@geo.tamu.edu
AF: Dept of Geology and Geophysics, Texas A&M University, College Station, TX 77843, United States
AB: The relationship between the Chicxulub impact and the paleontologically defined boundary between the Cretaceous and Tertiary periods is a hotly debated subject. The K-T complex, with its distinctive yellow spherule- rich clay layer, is capped by sandstone beds in streambed exposures along the Brazos River in Falls County, TX. Studies of the microfossils in the Falls Co. location show that the paleontological K-T boundary is stratigraphically removed from the yellow clay layer associated with Chicxulub. This study is an attempt to construct a 3-D image of the top of "event complex" by the use of geophysical methods. A near surface seismic refraction survey was completed in an area near the exposed K-T sections. Our seismic images may shed some light on competing theories as to the depositional environment at the time the sandstone bed was formed. Important seismically-resolved topographic features such as undulations and discontinuities could play a large role in shaping a better understanding of the K-T boundary complex origins.
DE: 0935 Seismic methods (3025, 7294)
DE: 8136 Impact phenomena (5420, 6022)
DE: 9350 North America
SC: Near-Surface Geophysics [NS]
MN: 2007 Fall Meeting