Investigating Sequestration Potential of Carbonate Rocks during Tertiary Recovery from a Billion Barrel Oil Field , Weyburn , Saskatchewan : the Geoscience Framework ( IEA Weyburn CO 2 Monitoring and Storage Project )
Introduction In Western Canada the application of CO2 injection for enhanced, ‘tertiary’ oil recovery is a relatively recent addition to the arsenal available to reservoir engineers. The first successful application of CO2 as a miscible fluid in Western Canada began in 1984 at Joffre Field, a Cretaceous marine siliciclastic reservoir in southern Alberta. A significant portion of the remaining proven conventional oil reserves in Western Canada, however, reside in large mature Paleozoic carbonate fields, such as the Mississippian Weyburn Field in SE Saskatchewan (Figure 1). In combination with economically dictated tertiary recovery schemes, these large fields could provide attractive geologic sites for future sequestration of greenhouse gases. An immediate challenge to geoscientists is to assess the ability of these geologic containers to store CO2 for geologically significant lengths of time.
Mineralogy and CO2 Storage at the Weyburn IEA CO2-EOR Site
Summary Water-rock reactions are critical to the short- and long-term storage of injected CO2. CarbonateCO2-fluid reactions releases CO2 while silicate-CO2-fluid reactions potentially store CO2 in the fluid and as newly formed carbonates. The detailed, quantitative mineralogy of the Weyburn reservoir is described in the context of flow units as defined by the operator of the Weyburn Field, EnCana Resources Ltd. Detailed, quantitative mineralogy is also presented for the units that overly the Weybrun Reservoir. Storage calculations show that even in a carbonte reservoir such as Weybrun, there are sufficient silicate minerals to provide long term storage of CO2 by reaction with silicates. Also, overlying units that represent a wide array of rock types have the capacity to store CO2 that might escape from the reservoir.
PHOTOGRAMMETRY AND ITS USES IN HIGHWAY PLANNING AND DESIGN
PHOTOGRAMMETRY MIGHT BE DESCRIBED AS THE PROCESS OF CONVERTING PHOTOGRAPHS INTO CONTOURED TOPOGRAPHIC MAPS. FORMERLY GROUND SURVEY METHODS WERE CONSIDERED THE ONLY RELIABLE MEANS OF OBTAINING ACCURATE TOPOGRAPHIC INFORMATION. IT IS NOW POSSIBLE TO DEVELOP TOPOGRAPHIC MAPS OF SPECIFIED ACCURACY BY MEANS OF AERIAL PHOTOGRAPHS WHICH ARE THEN SUBJECTED TO A SERIES OF PHOTOGRAMMETRIC PROCESSES SO THAT MAPS MAY BE DRAWN AT SCALES USEFUL IN HIGHWAY LOCATION AND DESIGN. /AUTHOR/