Software Tool Improves Fractured-Reservoir Characterization and Modeling

Abstract

This article, written by Technology Editor Dennis Denney, contains highlights of paper SPE 88785, "New Software Tool Improves Fractured-Reservoir Characterization and Modeling Through Maximized Use of Constraints and Data Integration," by K. Rawnsley, Shell Intl.; P. Swaby, SPE, SSL; S. Bettembourg, S. Dhahab, H. Hillgartner, and M. de Keijzer, Shell Intl.; P. Richard, and P. Schoepfer, PDO; and B. Stephenson and L. Wei, Shell Intl., prepared for the 2004 Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, 10-13 October. To enhance oil recovery from several fractured-carbonate reservoirs in Oman, Shell’s carbonate-development team and Petroleum Development Oman (PDO) applied a workflow and a research-software package aimed at better characterizing the complex subsurface. The work-flow comprised several steps, each supported by a multidisciplinary research program and implemented in an integrated-software environment for application to field development and enhanced-oil-recovery projects. The software tool, which interacts with existing static- and dynamic-modeling packages, produces integrated reservoir models including fracture-specific information. Introduction The main objectives of these studies were to provide enhanced constraints on fracture modeling in the subsurface. The following are important aspects of fracture systems, which typically are poorly constrained by subsurface data alone. - Accurate 2D and 3D characterization of structural objects, especially fracture corridors and the internal geometries of fault zones. - Organization of multiscaled fracture systems within mechanically layered rocks (i.e., the vertical extents of fractures intersected by wells). - Internal flow properties of the fractures. Several reservoir studies were carried out in parallel, for example in the northern Oman region, operated by PDO, providing an excellent opportunity to link observations made at the surface with the complete reservoir data sets. The current research builds on the understanding of the regional structural framework and evolution of North Oman from previous studies. The objective was to show how a software tool developed in Shell facilitated bringing research and field studies together to pro-vide enhanced reservoir characterization. Fig. 1 shows a generic workflow.