| This paper is focused on two key problems - distribution of coal seam, stability and regularity of enrichment, which limits the coal-seam methane in Daning-Jixian area. Through explored coal-seam methane wells, a relatively systematic research on distribution and stability of coal seam, preserving condition, characteristics of methane and regularity of permeability with high sequence stratigraphy, sedimentary environment analysis and integrated evaluation of fracture etc. Consequently, the most favorable exploration objectives are provided. The main achievements are as follows:1. In the research area, the coal series in late Palaeozoic era were mainly formed from epeiric sea - coastal plain environment. In this area, four major sedimentary systems of carbonate platform, barrier - platform, shallow delta and river - lake are identified.2. In Taiyuan - Shanxi section, six cycles of short term formation strata datum level and three mid term cycles of prdgradation, low retrogradation and low progradation can be identified. In research area and section, four mid term cycles, in which major coal accumulation occurred in top of mid term cycle and several short term cycles is included in one mid term cycle can be identified. On the basis of short and mid term cycles, 2 long term cycles were identified in coal seam.3. In this area, coal seams can be divided into 2 three level sequence, 4 four level sequence, 11 five level sequence. The classification of high resolution stratigraphy provides evidence and conception frame.4. Sedimentary environment of coal seam 8 in research area mainly is barrier -lagoon facies, in which the rich coal belt distributing direction is south - north. Coal seam 5 is in coastal plain environment, in which delta plain deposition is well developed. Its coal rich belt stretch from east to west.5. The characteristics of coal accumulating, lithology, composition of lithofacies and its spacial combination are all controlled by sedimentary environment. Basis on this cause and effect relation, sedimentation greatly determines the material basis and methane generation and the metric characteristics and physic property of reservoir and cap, which effects preserving condition together with relationship of coal seam and neighboring rock. Several deposition combinations have been divided on key coal seam 5 and 8 by researching, and evaluation on advantage of preservation condition of methane was conducted.6. Virtrinite is more likely form cleat system and has high permeability. Based on this point, permeability prediction of key coal seam 5 and 8 has done in this paper. In the surrounding area of well 4 well 5 of Jishi of the deep coal seam area, coal seam 5 and 8 are all have good permeability excepting the eastern outcrop area. In the surrounding areaof well 1, well 2 and well 3 of Jishi, coal seam 8 has favorable permeability and coal seam 5 has bad permeability.7. An integrated evaluation of coal seam fracture development in terms of coal seam breaking index and deforming coefficient to predict high permeability area. Degree of complexity on structure deforming can be evaluated qualitatively through K value contour map. High K value area has great deformation, which cause rich micro fracture and good permeability; in low K value area, the little deformation will lead to bad permeability.8. According to integrated analysis of deposition environment and fracture, high permeability area and favorable preservation area can be predicted. The most favorable exploration objective can be provided consequently.
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