Rucsandra Maria Corbeanu¹, Robert B. Szerbiak¹, Kristian Soegaard¹, George A. McMechan¹, Stephen H. Snelgrove², Craig B. Forster²
(1) University of Texas at Dallas, Richardson, TX
(2) University of Utah, Salt Lake City, UT

Abstract: 3-D internal distribution of heterogeneities in a fluvial channel reservoir derived from 3-D GPR interpretation - A case study from the Cretaceous Ferron Sandstone, Utah

Characterization of hydrocarbon reservoirs requires information about heterogeneities at a submeter scale in three dimensions. Heterogeneity in a fluvial channel reservoir analog from the Cretaceous Ferron Sandstone, Utah, is analyzed using sedimentologic data from outcrop and boreholes. These are integrated with 100 MHz 3-D ground-penetrating radar (GPR) data and with permeability measurements. Five architectural elements and bounding surfaces are described in the outcrop and boreholes and are interpreted in the GPR data. First- and second-order bounding surfaces are interpreted from reflections resolved with 200 MHz GPR data. Third-, fourth- and fifth-order bounding surfaces are erosional and have top-discordant relations with the reflections below the surface or downlap relations with the reflections above. Each architectural unit is characterized by specific radar facies and permeability structures. Migrated GPR amplitude distributions are good indicator of the horizontal heterogeneities inside each element. 3-D correlation functions computed from the GPR amplitudes show maximum correlation lengths of these internal features of 4-6 meters with horizontal anisotropy of 0.6-0.95. Sequential Gaussian simulation is used to spatially extrapolates sparse borehole permeability measurements into a continuous 3-D permeability volume. This 3-D reservoir analog volume is the main input needed for 3-D flow simulations.

AAPG Search and Discovery Article #90914©2000 AAPG Annual Convention, New Orleans, Louisiana