Back barrier facies of a microtidal coastline, Upper Cretaceous Blackhawk Formation, Utah

Conference · Tue Jan 01 00:00:00 EST 1985 · Geol. Soc. Am., Abstr. Programs; (United States)

OSTI ID:6196700

Kamola, D L

Protected lagoonal environments situated landward or prograding barriers, are characterized by low energy deposits which include flood tidal deltas, flood-dominated channel-fill sandstones, swamps (coal), and lagoon-fill siltstones. Flood tidal deltas consists of landward-dipping beds of sandstone which interfinger vertically and laterally with rooted and/or bioturbated lagoonal siltstones. Locally, individual beds of the flood tidal delta may be rooted or burrowed, which indicates discontinuous deposition of sediment into a lagoon. Channel-fill sandstones characterized by landward-oriented paleocurrent directions are interpreted to represent tidally influenced channels in a flood-dominated, microtidal setting. The majority of the lagoon-fill sediments are bioturbated, rooted, or burrowed siltstone, with brackish water bivalves Crossostrea, Brachidontes, Corbula and Anomia. Trace fossils Thalassinoides, Planolites, Palaeophycus, and Pelecypodichnus are common. Ophiomorpha-burrowed, medium grain size sandstone with abraded oyster shells is the only evidence of higher energy (storm-related) lagoonal deposition. Swamps are represented by low sulfur, low ash coal seams, with tree stumps, tree roots, and dinosaur tracks. Swamp environments prograded over sediment-filled lagoons, and are interpreted as the final stage of back barrier deposition.

• Research Organization: Univ. Utah, Salt Lake City (USA)
• OSTI ID: 6196700
• Report Number(s): CONF-8510489-
• Journal Information: Geol. Soc. Am., Abstr. Programs; (United States), Vol. 17; Conference: 98. annual meeting of the Geological Society of America, Orlando, FL, USA, 28 Oct 1985
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
SEDIMENTARY ROCKS
PALEONTOLOGY
PETROLOGY
STRATIGRAPHY
UTAH
COAL
COAL SEAMS
CRETACEOUS PERIOD
DEPOSITION
FOSSILS
GEOLOGIC FORMATIONS
GEOLOGIC HISTORY
CARBONACEOUS MATERIALS
COAL DEPOSITS
ENERGY SOURCES
FEDERAL REGION VIII
FOSSIL FUELS
FUELS
GEOLOGIC AGES
GEOLOGIC DEPOSITS
GEOLOGY
MATERIALS
MESOZOIC ERA
MINERAL RESOURCES
NORTH AMERICA
RESOURCES
ROCKS
USA
580300* - Mineralogy
Petrology
& Rock Mechanics- (-1989)