Identifying New Opportunities in a Mature Basin Using Genetic Analysis: From Example from the Mississippian Banff Formation, Alberta, Canada
Robert H. Alway1, Rebecca Buckley1, Eileen Scott2, Robert J. Leibel2, Wayne Kirchner2, Lee Wamsteeker2, John Ardic1, Fred Haueter1, Art French1, Roger Bloch1, and Tom Pasquini1
1ExxonMobil Exploration Company, Houston, TX
2ExxonMobil Canada West, Calgary, AB, Canada
Gas pool discoveries from the Banff Formation, WCSB with gross production rates up to 100 mcf/d are reported from stratigraphically trapped transported dolomitized carbonate grainstones (up to 30% porosity; several hundreds of mD to several Darcies of permeability). These reservoirs were deposited along a passive continental margin, with the periodic influence of Antler-age tectonics. Analysis of 2_D and 3_D seismic data to detect favorable amplitude responses is used qualitatively as a porosity indicator. However, recent drilling results by EMCW 150 Km south of the known production, encountered shale while testing comparable amplitude responses.
Successful play evaluation required a complete understanding of the hydrocarbon system from the regional to the prospect scale. A regional sequence stratigraphic framework was constructed using select well/core/seismic control to address play risks. Findings suggest basement and Devonian carbonate platforms influenced Banff paleo-thickness, faulting/fracturing and dolomitization processes. Tectonic-induced subsidence controlled Banff ramp architecture, which in turn influenced the distribution of reservoir facies. Seismic and well data resolution is too coarse to adequately de-risk trap/seal play elements. However by understanding each play element a prospective fairway of 10000 Km2 was identified within of a 500-Km long play fairway.
The technical evaluation exemplifies a holistic and genetic approach to the search for hydrocarbons. Our strategy focused on defining regional EOD's and diagenetic fairways, in order to focus 2_D and 3_D seismic to best image Banff amplitude responses. It is hoped that this example will provide insight to others as to how to approach opportunities that fill in the gap between exploration and production in other competitive mature basins to achieve superior results in the future.
AAPG Search and Discover Article #90078©2008 AAPG Annual Convention, San Antonio, Texas