GEOLOGY: K-T boundary - Sussex site, north of Casper, Wyoming. Collecting a sample of rock at the K-T boundary for museum display. The sample includes Cretaceous rocks under the boundary, the boundary layer, and Tertiary sediments above the boundary. The front and top of the partially excavated bloc are protected by a layer of aluminum foil and a plaster jacket (behind rock hammer). The entire bloc will eventually be wrapped up in a plaster jacket for safe removal and transport.