| Considering the complexity and variety of volcanic lithology,lithofacies and fracture type of volcanic reservoir in vertical and literal distribution,this dissertation,on the basis of former research findings and in light of the structural geology,reservoir sedimentology and igneous petrology,makes full use of seismic,logging and drilling data to classify the volcanic lithology and lithofacies of third section of Yingcheng in detail and identify the features of volcanic reservoir in petrology and fracture in Anda Subsag.By the lithology identification and contrast between volcanic interval of the third section of Yingcheng Formation drilled by 8 coring wells and logging data in the study area, the fact that the Subsag mainly consists of intermediate-basic volcanic rocks is confirmed. The coring data and logging identification technique determine that the main types of reservoir space are air hole, residual air hole, hole in amygdaloid and shrinkage joint. In the 8 coring wells, 4 types of volcanic lithofacies such as surb-volcanic rock facies, outbreak facies, effusion facies and volcanic-sedimentary facies can be identified.Based on the research of lithology and lithofacies for volcanic reservoir of coring sections and their relations with reservoir space,volcanic rocks with good physical properties in the third section of Yingcheng Formation of this area are determined to be andesite and andesitic eruptive breccias.Comprehensive utilization of cores, microscopic identification, logging, seismic and other data, we set up the plane phasing pictures of the third section of Yingcheng volcanics in Anda Subsag. On plane, the facies following the crater are volcanic conduit facies, extrusive facies, explosive facies, effusive facies and volcanogenitic sedmentary facies. Also, we predict the distribution of volcanic bodies, which mainly controlled by Xu fracture, beaded on both sides of the Xu fault distribution, mainly towards the North West.
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