Investigating Cap Rock Efficiency of Laffan Shale Formation in Sirri Oil Fields, Offshore Iran
This study investigates the sealing efficiency of the Laffan Shale Formation as the caprock of the Sirri oil fields. Available information sources from Laffan Formation include drillhole core samples, daily drilling and geology reports and petrophysical logs of drilled wells. Type and quantity of minerals are determined by direct and indirect methods. In the next step in order to study the distribution of minerals and fabric of the shale samples SEM photomicrographs are taken. Petrophysical characterization by mercury porosimetry and laboratory experiments to measure total organic carbon and cation exchange capacity of samples are the next steps. Pore pressure of Laffan Formation is determined by using data obtained from both acoustic and resistivity logs. Laffan Formation in Sirri oil fields is a shale formation comprising kaolinte clay mineral and calcite and quartz cement. It has a very low permeability. Laffan is a relatively thin and brittle formation but the presence of organic-rich layers and being buried at deeper depth has improved the chance of its lateral continuity and can be classified as a good seal. This study shows that similar results are obtained from direct and indirect methods in determining type of and mineralogy and also indicates that good correlations is achieved when taking into account of permeability and total organic carbon. The next purpose of this paper is to provide a research process that can be applied in similar geological settings.
Key Word: Caprock-sealing efficiency; Shale formation; Clay mineral; X-ray diffraction; Scanning electron microscopy; Ductility; Total organic content
AL-Bazali, T.M., Zhang, J. & Sharma, M.M. (2005). Measurement of the Sealing Capacity of Shale Caprocks. SPE Paper Number 96100-MS.
Bennett, R. H., Bryant, W.R. & Hulbert, M.H. (1991). The Microstructure of Fine-grained Sediments, from mud to shale. New York: Springer-Verlag.
Cook, J. (1999). The effects of Pore Pressure On the mechanical and physical properties of shales. Oil & Gas Science and Technology-Rev, IFP, 54(6), 695-701.
Eslinger, E. & Pevear, D. (1988). Clay Minerals for Petroleum Geologists and Engineers. Tulsa: SEPM.
Ghazban, F. (2009). Petroleum Geology of the Persian Gulf. Tehran: University of Tehran Press.
Ho, A., Fokker, P. A. & Orlic, B. (2005). Caprock Integrity of Deep Saline Reservoirs and Coupled Processes. Netherlands Institute of Applied Geosciences.
Ingram, G. M. & Urai, J.L. (1999). Top-seal Leakage through Faults and Fractures, the Role of mudrock Properties. Australia: Shell Development.
International Atomic Energy Agency. (2003). Guidelines for Radioelement Mapping Using Gamma Ray Spectrometry Data (IAEA-TECDOC-1363). Vienna.
Ma,C. & Eggleton, R.A. (1999). Cation Exchange Capacity of Kaolinite. Clays and Clay Minerals Journal, 47(2), 174-180.
Magoon, L. B. & Dow, W. G. (1994). The Petroleum System: From Source to Trap. Tulsa: American Association of Petroleum Geologists.
Nederlof, M.H. & Mohler, H.P. (1981). Quantitative investigation of trapping effect of unfaulted caprock. AAPG Bulletin, 65, 964.
Pritchett, W.C. (October 1980). Physical properties of shales and possible origin of high pressures. SPE Journal, 20(5), 341-348.
Schlömer, S. & Krooss, B. M. (August 1997). Experimental characterization of the hydrocarbon sealing efficiency of cap rocks. Marine and Petroleum Geology Journal, 14(5), 565-580.
Surdam, R.C. (1997). Seals, Traps, and the Petroleum System. Tulsa: American Association of Petroleum Geologists.
Welton. J. E. (1984). SEM Petrology Atlas. Tulsa: the American Association of Petroleum Geologists.
Wilson, M.J. (1987). A Handbook of Determinative Methods in Clay Mineralogy. Aberdeen: Macaulay Institute for Soil Research.
Zweigel, P., Lindeberg, E., Moen, A. & Wessel-Berg, D. (2004). Towards a Methodology for Top Seal Efficacy Assessment for Underground CO2 Storage. Paper Presented at 7th Greenhouse Gas Control Technologies conference (GHGT-7), Vancouver, Canada.
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