Reworking of Cretaceous dinosaurs into Paleocene channel deposits, upper Hell Creek Formation, Montana

Journal Article · Sat Sep 01 00:00:00 EDT 1990 · Geology; (USA)

DOI:https://doi.org/10.1130/0091-7613(1990)018<0874:ROCDIP>2.3.CO;2· OSTI ID:6212694

Lofgren, D L ^[1]; Hotton, C L ^[2]; Runkel, A C ^[3]

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1. Univ. of California, Berkeley (USA)
2. State Univ. of New York, Binghamton (USA)
3. Univ. of Texas, Austin (USA)

Dinosaur teeth from Paleocene channel fills have been interpreted as indicating dinosaur survival into the Paleocene. However, enormous potential for reworking exists because these records are restricted to large channel fills that are deeply incised into Cretaceous strata. Identification of reworked fossils is usually equivocal. This problem is illustrated by the Black Spring Coulee channel fill, a dinosaur-bearing Paleocene deposit in the upper Hell Creek Formation of eastern Montana. In this example, the reworked nature of well-preserved dinosaur bones is apparent only after detailed sedimentological and palynological analysis. Because of the potential for reworking, dinosaur remains derived from Paleocene fluvial deposits should not be assigned a Paleocene age unless the (1) are found in floodplain deposits, (2) are articulated, (3) are in channels that do not incise Cretaceous strata, or (4) are demonstrably reworked from Paleocene deposits. To date, reports of Paleocene dinosaurs do not fulfill any of these criteria. Thus, the proposal that dinosaurs persisted into the Paleocene remains unsubstantiated.

• OSTI ID: 6212694
• Journal Information: Geology; (USA), Journal Name: Geology; (USA) Vol. 18:9; ISSN GLGYB; ISSN 0091-7613
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
AGE ESTIMATION
ANIMALS
CENOZOIC ERA
CRETACEOUS PERIOD
DEATH
DETECTION
FEDERAL REGION VIII
FOSSILS
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGIC HISTORY
GEOLOGIC STRATA
GEOLOGIC STRUCTURES
MESOZOIC ERA
MIXING
MONTANA
NORTH AMERICA
PALEONTOLOGY
PALYNOLOGY
RECOMMENDATIONS
SEDIMENTATION
TERTIARY PERIOD
USA