Bones and Rocks of the Upper Cretaceous Two Medicine-Judith River Clastic Wedge Complex, Montana part of Integrating Research and Education:Montana Geoheritage Project:Montana-Yellowstone Geologic Field Guide Database:MT Field Guides
The purpose of this field trip is to provide an overview of the paleontologic, stratigraphic, and paleoenvironmental aspects of the Upper Cretaceous Two Medicine-Judith River clastic wedge in western Montana. Strata of the Two Medicine Formation yielded the first evidence of such dinosaur social behavior as nest construction and parental care, and have provided important information concerning the processes of bonebed formation in the fossil record. The correlative Judith River Formation in Montana has yielded an abundant and diverse dinosaur fossil record primarily preserved as transported and concentrated accumulations of vertebrate remains ("microsites"). The geology and paleontology of four fossil localities [Seven Mile Hill, Shield's Crossing, Willow Creek Anticline (Egg Mountain), and the Badger Creek/Two Medicine River confluence] are described, but precise details concerning the locations of the sites are not given in the field guide.

Upper Cretaceous-Paleocene Sequence, Bug Creek Area, Northeastern Montana part of Integrating Research and Education:Montana Geoheritage Project:Montana-Yellowstone Geologic Field Guide Database:MT Field Guides
Study of the Late Cretaceous-Paleocene sequence in the Bug Creek Area and the rest of the Fort Peck Fossil Field has contributed greatly to our understanding of the paleoecology and stratigraphy of dinosaur extinction and the primary radiation of Tertiary placental mammals. The area features at least 133 species of spores and pollen, 93 species of Cretaceous vertebrates (including 30 species of mammals and 19 species of dinosaurs), 24 species of Paleocene mammals, as well as the oldest ungulate and primate specimens ever found. Fossil leaves and wood have also been described. The area also includes well-studied localities of the K/T boundary containing Ir-rich clay and shocked quartz. No section of terrestrial sediments across the K/T boundary has been studied in as many ways as this one. This has been and will continue to be a major locality at which to study evidence for various hypotheses about the events at the K/T boundary.