Chicxulub Revealed with New Seismic and Gravity Data

Experiment: In early 2005 we acquired a new highresolution grid of seismic and gravity data across the Chicxulub impact crater (Fig. 1). These data include ~1500 km of reflection profile, ~36500 airgun shots that were recorded on 28 ocean bottom seismometers and 87 land seismometers, and ~7600 km of gravity data. Data are being processed at UTIG (University of Texas at Austin Institute for Geophysics), and the Universities of Cambridge and Imperial in the UK. Some targets of the experiment are: to map the extent and asymmetry of the slumped Cretaceous blocks around the crater, to determine the extent of the anomalous low velocity zone beneath the peak ring, to map the extent and shape of the stratigraphic uplift, to investigate changes in ejecta thickness around the crater, and to collect site survey data for two proposed IODP drill holes.