Abstract: Constructing 3-D Geologic Models for Reservoir Characterization and Thermal Development of Tulare Formation Reservoirs, Cymric Field, San Joaquin Basin, California

MCCOLLOM, ROB, Consultant, Houston, CA; ED VEITH, Aera Energy LLC

The purpose of this paper is to describe the multi-disciplinary approach employed during reservoir characterization and 3-D model construction of the Pliocene-Pleistocene Tulare formation in the Cymric field, San Joaquin Basin, California. The reservoir team performed an integrated evaluation combining geological, geophysical, and engineering data for the purpose of developing the reservoir with horizontal producers and vertical steam injection wells.

The reservoirs occur in a series of northwestward trending anticlines and synclines and represent a progradational clastic wedge of nonmarine sediments that thickens northeastward into the San Joaquin Basin. The Tulare reservoirs are heavy oil reservoirs and are under steamflood. Detailed structural information (fault and fold geometry) and compilation of accurate oil-water and gas-oil contact information is critical for thermal recovery well design and placement.

The Tulare reservoirs were described using the following data types: 3-D seismic data, well log data, injection data, temperature log curves, and production data. The information from the various data sources was incorporated in 3-D models for comparison and volumetric analysis. The goal of the 3-D modeling was to 1) build repository for geologic, geophysical, and engineering data, 2) delineate net pay sand and evaluate net pay sand connectivity laterally and vertically 3) calculate pore volume, hydrocarbon pore volume, and OOIP by fault block and field wide, 4) evaluate fault seals, 5) examine reservoir juxtaposition across faults, and 6) create optimum well trajectories in 3-D model for the development drilling program.

AAPG Search and Discovery Article #90911©2000 AAPG Pacific Section and Western Region Society of Petroleum Engineers, Long Beach, California