Print this pageTesting a Model for Recognizing High-Resolution Accommodation Changes in Paralic Coal Seams in the 
Book
Cliffs of Eastern Utah, U.S.A.
Roy C. Davies1, Ron Boyd2, John A.
Howell3, Stephen S. Flint1, and Claus Diessel2
1 University of Liverpool, Liverpool, United Kingdom
2 University of Newcastle, Callaghan, Australia
3 University of Bergen, Bergen, Norway
One of the key issues to be addressed in modern stratigraphic research is
the correlation and integration of marine and terrestrial (non-marine) records
of accommodation change. This paper addresses this issue by using a combination
of transgressive / regressive marine strata and terrestrial organic facies to
produce an integrated model for the evolution of the marine and terrestrial
components of the Upper Cretaceous Blackhawk Formation in the Book
Cliffs of
Eastern Utah, USA.
Systematic variations in inorganic mineral, vitrinite and inertinite content enable us to identify a high-resolution record of accommodation change throughout the deposition of laterally extensive coal seams from the Aberdeen, Sunnyside and Desert Members of the Blackhawk Formation. By plotting the data from these seams on a conceptual coal facies diagram, we are able to demonstrate that the characteristics of the coals reflect the well-documented decrease in accommodation creation throughout the deposition of the Blackhawk Formation (approximately 3.5 My). This shows that terrestrial sediments can provide a comparable record of accommodation change to the time-equivalent marine strata. Detailed work on the Sunnyside Member also suggests that terrestrial strata may preserve a higher resolution and more complete record of accommodation change than the temporally and spatially equivalent shallow-marine strata.
This work has a range of important implications including: 1) documenting the effects of accommodation change on coal formation, 2) comparing the responses of temporally and spatially equivalent terrestrial and marine strata to accommodation change, and 3) demonstrating a structured approach to correlating marine and terrestrial strata.
AAPG Search and Discovery Article #90039©2005 AAPG Calgary, Alberta, June 16-19, 2005