If your research or interests lie in the geology of South Dakota, then the state's Geological Survey Program Web site is for you. Offered are online publications and maps, a geologic reference database, a lithologic logs database, digital base maps, a water quality database, and several other quality information sources worth checking out.

Philip W. Stoffer and USGS colleagues wrote this report (.pdf format) on the marine K-T boundary interval that occurs throughout the Badlands National Park region of South Dakota. Data from marine sediments (supported by paleontological correlation, sequence stratigraphy, magnetostratigraphy, and strontium isotope geochronology) suggest that several asteroid impacts may be preserved in the...