Electrical and electromagnetic methods for reservoir description and process monitoring. Annual report, October 1, 1991--September 30, 1992

During FY-91 a coordinated electrical and electromagnetic (em) geophysical research program for petroleum reservoir characterization and process monitoring was initiated. Parties involved in this program include Lawrence Berkeley Laboratory (LBL), Lawrence Livermore Laboratory (LLNL), Sandia National Laboratory (SNL), and University of California at Berkeley (UCB). The overall objectives of the program are: To integrate research funded by DOE for hydrocarbon recovery into a focused effort to demonstrate the technology in the shortest time with the least cost. To assure industry acceptance of the technology developed by having industry involvement in the planning, implementation, and funding of the research. To focus the research on real world problems that have the potential for solution in the near term with significant energy payoff. Specific research activities conducted through this integrated effort have been in the following five general areas: em modeling development; data interpretation methods development; hardware and instrumentation development; EOR and reservoir characterization; and controlled field experiments. At LBL/UCB research has been focused on activities (1), (2), and (5) in FY92. The primary focus of these activities is in the development of reliable inversion and imaging schemes that can yield conductivity distributions from measured electrical and em field data. The development of accurate forward modeling algorithms and the high-quality scale model experiment are necessarily the early part of the field experiment design and the inversion scheme development for ultimately monitoring the front tracking in existing reservoirs. Technical progress for the following activities are summarized in this report: tim-domain electromagnetic (TEM) scale model; inversion and imaging of em data; and controlled field experiments