Publication Date:
2006-07-01
Description:
The Sunnyside Member of the Upper Cretaceous Blackhawk Formation in the Book Cliffs of eastern Utah provides an ideal opportunity to investigate high-resolution sequence-stratigraphic correlation between shallow-marine and terrestrial strata in an area of outstanding outcrop exposure. The thick, laterally extensive coal seam that caps the Sunnyside Member is critical for correlating between its shallow-marine and terrestrial components. Petrographic analysis of 281 samples obtained from 7 vertical sections spanning more than 30 km (18 mi) of depositional dip enabled us to recognize a series of transgressive-regressive coal facies trends in the seam. On this basis, we were able to identify a high-resolution record of accommodation change throughout the deposition of the coal, as well as a series of key sequence-stratigraphic surfaces. The stratigraphic relationships between the coal and the siliciclastic components of the Sunnyside Member enable us to correlate this record with that identified in the time-equivalent shallow-marine strata and to demonstrate that the coal spans the formation of two marine parasequences and two high-frequency, fourth-order sequence boundaries. This study has important implications for improving the understanding of sequence-stratigraphic expression in terrestrial strata and for correlating between marine and terrestrial records of base-level change. It may also have implications for improving the predictability of vertical and lateral variations in coal composition for mining and coalbed methane projects. Roy Davies is a postdoctoral researcher for the Center for Integrated Petroleum Research at the University of Bergen in Norway. His research interests include coal petrology, sequence stratigraphy, reservoir modeling, and the integration of electromagnetic and seismic data. He holds a B.Sc. degree and a Ph.D. in geology from the University of Liverpool, United Kingdom. John Howell is a professor at the Center for Integrated Petroleum Research at the University of Bergen in Norway. His research interests include reservoir modeling, sequence stratigraphy, and clastic sedimentology. He holds a B.Sc. degree in geology from the University of Cardiff and a Ph.D. in geology from the University of Birmingham, United Kingdom. Ron Boyd is an associate professor at the University of Newcastle in Australia, where his research interests include marine geoscience, sedimentology, and stratigraphy. He holds a B.Sc. degree and a Ph.D. from the University of Sydney and has previously taught and researched at Louisiana, Dalhousie, and New Hampshire universities, the Royal Australian Navy Research Labs, Geomar Institute Kiel, and PanCanadian Petroleum Calgary. Stephen Flint holds a personal chair in stratigraphy and petroleum geology at the University of Liverpool in the United Kingdom. After obtaining his Ph.D. from the University of Leeds in 1985, he spent 6 years working for Shell Research in the Netherlands before returning to the United Kingdom to set up the Stratigraphy Group at the University of Liverpool in 1991. Claus Diessel is an emeritus professor at the University of Newcastle in Australia and has extensive research interests in many aspects of coal petrology, as well as its application to sequence stratigraphy. He holds a Dipl. Geol. and Dr. Ret. Nat. from the University of Berlin, Germany.
Print ISSN:
0149-1423
Electronic ISSN:
1943-2674
Topics:
Geosciences
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