Geological Characterization for the Iea Ghg Weyburn-Midale CO₂ Monitoring and Storage Project: Past Successes and Future Challenges

Ben Rostron¹ and Steve Whittaker^2
1Earth & Atmospheric Sciences, University of Alberta, Edmonton, AB, Canada
²Canada Capital Energy Corporation, Regina, SK, Canada

In July 2000, a major research project was initiated to study the geological storage of CO₂ as part of a EOR project planned for the Weyburn Field in Saskatchewan, Canada. A major objective of the IEA GHG Weyburn CO₂ monitoring and storage project was to assess the integrity of the geosphere encompassing the Weyburn oil pool for effective long-term storage of CO₂. Over the period 2000-2004, a diverse group of 40+ geoscientists worked on a geological characterization at both a regional scale (100 km beyond the field) and a more detailed scale (10 km beyond the field). Over 140 stratigraphic units were mapped from selected wells in the area. Geological mapping was supplemented with 2D seismic lines, aeromagnetic data, air photo and satellite imagery, and core examination. Regional “deep”, regional “shallow”, and local “shallow” hydrogeological studies were undertaken to determine the type of fluids present, as well as their flow directions and flow rates. All of this information was assembled into a 3D geological model that was used for risk assessment in the project.

The challenges faced in the first phase of the project were threefold: i) dealing with the volume of data (i.e., hundreds of wells within the study area); ii) geological and geophysical mapping revealed the presence of numerous “discontinuities” in the geosphere. Determining the open or closed nature of these discontinuities was not possible; and iii) little attention was paid to the horizon below the injection zone but the risk assessment simulations later indicated possible downward movement of CO₂ from the reservoir. To address these challenges, the Final Phase of the IEA GHG Weyburn-Midale CO₂ monitoring and storage project has initiated research studies dealing specifically with the above issues.

This talk will present a summary of the results obtained to date, and future plans, for the project.

AAPG Search and Discover Article #90078©2008 AAPG Annual Convention, San Antonio, Texas