Abstract: Integration of Seismic, Crosswell, and Geologic Data for Reservoir Characterization at Rabbit Hills Field, North-Central Montana
Curtis A. Link, Charles J. Wideman, Karen W. Porter
Characterization of a petroleum reservoir requires integration of data sets to provide a field-scale model of the reservoir. At Rabbit Hills field in north-central Montana a reservoir characterization program is being conducted by a research team of geophysicists, geologists, petroleum engineers, mathematicians, and computer scientists, funded jointly by the Department of Energy and the Montana Science and Technology Alliance.
Part 1. Rabbit Hills field is a structurally enhanced stratigraphic trap. Oil is produced from secondary porosity in bioclastic limestone of a braided-channel complex in the upper Bowes Member of the middle Jurassic Piper-Sawtooth Formation. A 1.4 square mile surface seismic survey was conducted over the field, using a dynamite source of three pounds at 10 ft, and an 82.5 × 82.5 ft bin size. The target depth is approximately 4,000 ft. Data are of good quality, with frequencies beyond 80 Hz and high fold coverage over the field, making them suitable for structural and stratigraphic interpretation. Data support the structural and stratigraphic aspects of the geologic model.
Part 2. A crosswell seismic experiment was conducted between two field wells 950 ft apart to obtain data for tomographic and high-resolution reflection imaging. The downhole source was a nondestructive, piezoelectric 'bender'; the receiver string consisted of five hydrophones. An objective of the experiment was to test the possibility of recording crosswell data with receivers inside the production tubing. The data show a 20-dB loss of signal strength compared to data recorded without tubing. Tomograms and reflection images are being integrated with surface seismic and geologic model data sets.
AAPG Search and Discovery Article #90952©1996 AAPG Rocky Mountain Section Meeting, Billings, Montana