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C H I N A P E T R O L E U M E X P L O R A T I O N ABSTRACT Genetic Types and Hydrocarbon Exploration Directions of Volcanic Rocks in Eastern and Western Junggar/ Wu Xiaozhi 1, Qi Xuefeng 2, Tang Yong 2, Li Bohua 1 //1. Research Institute of Petroleum Exploration and Development, PetroChina, Beijing 100083; 2. Research Institute of Petroleum Exploration and Development, PetroChina Xinjiang Oilfield Company, Karamay City, Xinjiang Uygur Autonomous Region 834000 Abstract: The Carboniferous-Permian volcanic rocks in eastern and western Junggar have evolved into the practical hydrocarbon exploration displacement series of strata. Practice shows that the reservoir formation of the Carboniferous-Permian volcanic rocks is mostly based on the "source control theory", as well as the reservoir formation and distribution is controlled by regional structural evolution, i.e., the control of the development of Carboniferous hydrocarbon generating sags and the distribution of source rocks. The Carboniferous volcanic rocks in western Junggar belong to systematic marine and continental intermediate-basic volcanic rock assemblages and are characterized by the convergence of island-arc transitional crust volcanic rocks. The Carboniferous volcanic rocks in eastern Junggar belong to basic and intermediate-acid rock assemblages and are characterized by early island-arc compression and late intraplate extension. Permian volcanic rocks are formed by intraplate extension after collision stage. The Carboniferous hydrocarbon generating sags and source rocks are mainly formed in the anterior and posterior margin of the Kelameili island-arc belt in eastern Junggar. The Permian hydrocarbon generating sags and source rocks are mainly formed in the back-arc extensional basin in the fault zone in northwestern margin and the Santanghu area in eastern margin. The target and domains of exploration for oil and gas in Carboniferous-Permian volcanic rocks are around the development zones of inherited structures, i.e., the fault zone in northwestern margin of western Junggar (the Karamay-Baikouquan fault zone and the Hongshanzui-Chepaizi fault zone), the Kelameili orogenic zone in eastern Junggar (the Kupu-Santanghu Basin, the Beisantai bulge-jimusaer sag, the Dajing-Shiqiantan area), the Ludong-Wucaiwan area and Mobei bulge in northern Junggar. Key words: volcanic rock; structural setting; exploration directions; favorable belts; Carboniferous-Permian; eastern and western Junggar Forming Patterns and Distribution Laws of Gas Reservoir in Northeastern Ordos Basin during Paleozoic/Yao Jingli 1, 2, Huang Jiansong 1, Zheng Lin 3, and Li Zemin 3 //1. College of Sedimentology, Chengdu Institute of Technology, Chengdu City, Sichuan Province 610059; 2. Exploration & Development Research Institute of PetroChina Changqing Oilfield Company, Xi'an City, Shaanxi Province 710018; 3. Technological Center of Changqing Industrial Group, Xi'an City, Shaanxi Province 710018 Abstract: Through analysis on the history of hydrocarbongeneration from source rocks, paleo-structural evolution features and gas reservoir-forming composition, period of time, and gas reservoir types, it is regarded that the northeastern Ordos Basin is different from the middle and the south for their different thermal evolution degrees of organic burials of gas source rocks. Influenced by multi-stage structural uplift, gas migration, accumulation, and reservoir formation in the northeastern Ordos Basin experience two stages, that is, the early stage and the late stage. The reservoirs formed at the early stage are mainly concentrated in the south of the studied area and feature in near-sources formation under high temperature and high pressure. At the late stage, owing to the intense structural movement and the lost of abnormal pressure of regional sealing beds, gas migrates and accumulates upward and the cross reservoir-forming composition is developed. Therefore, according to the features of reservoir temperature and pressure and the process of reservoir formation, the gas reservoir-forming pattern of the area is summarized as three stages, that is, the high temperature and high pressure stage, the high temperature and low pressure stage, and the adjustment stage of temperature and pressure. On the basis of this, controlling factors and distribution laws of gas reservoirs are discussed, indicating a direction for Paleozoic gas exploration in the area. Key words: northeastern Ordos basin; Paleozoic; natural gas; reservoir-forming pattern; the law of gas reservoir distribution Reservoir Types and Controlling Factors of Reservoir Formation in Fuyu Oil Beds of Zhaoyuan-Taipingchuan Area, Songliao Basin/Shen Anjiang 1, Wu Haibo 2, Sun Hui 1, Guo Huikun 2, Luo Xianying 1 //1 PetroChina Hangzhou Institute of Geology, Hangzhou City, Zhejiang Province 310023; 2 Institute of Exploration and development, Daqing Oil Field Limited Company, Daqing City, Heilongjiang Province 163712 Abstract: Based on the analysis of structural characteristics and evolution, anatomise of hydrocarbon reservoirs and analysis of falling drills, eight types of reservoirs are recognized, i.e., the layer anticlinal reservoir, the fault block reservoir, the fault-nose reservoir, the structural fault reservoir, the sand lens reservoir, the up-dip pinch-out sandstone reservoir, the lithologic-structural reservoir, the lithologic fault reservoir. The controlling factors of reservoir formation are concluded in seven respects, i.e., the oil source condition, the effective reservoir, the power of hydrocarbon migration, the migration pathway, the effective trap, the source-reservoir-cap assemblage, and the preserving condition at the late stage. Five patterns of reservoir formation are summarized, i.e., the multi-stage and multi-directional reservoir of structural uplift zone, the upper source rock and lower reservoir near oil sources and sags, the multi-source reservoir of discordogenic fault communication, the fault-screened reservoir-forming pattern of slope zone, and the reservoir of negative structure. According to the analysis, the key time for reservoir formation in the area is the end of sediments in Nenjiang and Mingshui Formations. Key words: Songliao Basin; Zhaoyuan-Taipingchuan Area; Fuyu Oil Beds; reservoir type; the controlling factor of reservoir formation; the pattern of