Integrated Evaluation And Exploration Targets Optimization In Garmsar Block, Lran

Since China's reform and opening up to outsider world, Chinese economy has thrived rapidly and energy demand, especially demand for oil, has soared. But the recoverable oil reserves in China are decreasing after exploration and production for near half century, and the newly-discovered proven reserves fall far behind demand from economy development of our country. Shortage of energy reserves has threatened country security and become a bottleneck to restrict sustainable economy development of China. To solve this problem, China Petroleum & Chemical Corporation (SINOPEC) made a strategy called "Develop west of China, Stabilize east of China, Explore south of China and Expend oversea market" to increase energy reserves. With this strategy, SINOPEC has endeavored to participate in oversea oil exploration and development projects.Iran is rich in oil and gas reserves and is one of important oversea market for SINOPEC, Garmsar block is a important exploration area in Iran. Garmsar block is located in Central Iran Basin and has certain hydrocarbon potential according to past exploration records. Since 2006, SINOPEC has conducted Surface Geology Survey, Gravimetric & Magnetic Survey and 2D Seismic Survey in Garmsar Block, petroleum geology condition research has been made following these surveys results. But integrated and systematic geology evaluation to Garmsar block has not been conducted yet up to now. Therefore, in order to find oil and gas within a reasonable term, outline reserves and enter commercial production phase, the essential work for SINOPEC is making an integrated evaluation to Garmsar block and then optimizing exploration targets.Based on existing data and information such as seismic data, gravimetric data, field geology survey data, drilling data within and surrounding the area, as well as information of discovered oil and gas reservoirs, this Subject carried out systematic study on fundamental petroleum geology condition and key factors controlling reservoir formation in Garmsar block, Central Iran basin. Combined with structure interpretation, profitable traps are evaluated, and drilling targets are optimized.Through studies in this Subject, we have achievements as follows: 1) By way of structure analysis, this Subject expatiates on tectonic evolution background, and points out structural framework in Garmsar block.2) By way of multidisciplinary analysis including stratigraphic geology, sedimentology, sequence stratigraphy, the Subject accomplished sequence analysis in scale of parasequence, and classified sedimentary facies in different member of Qom formation.3) Based on large number of testing data and geological analysis results, the Subjectt studied source rock condition and evaluated hydrocarbon generation potential.4) Based on reservoir property analysis, the Subject pointed out potential reservoir-caprock assemblage in Garmsar Block.5) Through dissection of discovered oil and gas field (reservoir), and combined with petroleum geological condition in Garmsar block, the Subject summarized key factors controlling reservoir formation.6) Exploration Risks for Garmsar block:crack is the important reservoir space and the crack reservoir has severe heterogeneity, but there is no good means to predict crack reservoir precisely so far. Hydrocarbon-generating potential in Garmsar block remains uncertainty, whether source rock in this block has sufficient potential to form big oil and gas field still need to be studied.7) Based on the integrated studies, we evaluated profitable traps and finally put forward deployment for further exploration targets.Based on the integrated geological research, this Subject summarized exploration advantages and exploration risks in Garmsar Block and provided concrete suggestions for future exploration.