A pedotype approach to latest Cretaceous and earliest Tertiary paleosols in eastern Montana

摘要: A pedotype approach to the study of paleosols emphasizes individual profiles. It is an alternative geosols, which are laterally extensive suites paleosols, or pedofacies, pedogenically distinctive sedimentary facies. This first across Cretaceous-Tertiary boundary in eastern Montana. Pedotypes allow assessment sedimentation and fossilization. The sequence at Bug Creek one high temporal resolution, because most available geological time can be accounted for by differing degree development inferred each pedotype. Paleosols include pedotypes that preserve plant fossils well, but were unfavorable preservation fossil vertebrates. also reassessment ecosystem change. Despite indications catastrophe boundary, array Paleocene Cretaceous not strikingly different. Upper Hell Formation includes interpreted as gleyed Alfisols, Inceptisols, Entisols probably formed under seasonally water-logged forest mean annual rainfall order 900-1200 mm. Most lower Tullock Histosols, some Inceptisols bald cypress swamps a humid climate with >1200 mm rainfall. Broadly comparable present before after although flood-plain lived chemically little more oligotrophic than paleosols. modest difference supports idea change coaly facies earliest was local shift environment. Such changes do begin account profound disruption specific composition animal communities