| This thesis provides an eva reservoir assessmentluation of the reservior characteristics anddistribution of the continental shale in the research area of Section Chang7of the YanchangSet of the Triassic by means of the analyses of large number of samples with the geophysicalwell logging technology based on the collection of the geological, geochemical and reservoirdata from Ganquan District of the Ordos basin. The research resaults are as follows:(1) Section Chang7of the Yanchang Set mainly covers deep and half deep lakesedimentations, with rich organic shales developing at its bottom: thin in the northeast, thick inthe southwest,28~68m in thickness and1000～1500m in depth, with better continuity andrelatively stable distribution. The thicker area is located in the center of the basinsedimentation.(2) The shale in Section Chang7of the Yanchang Set contains high clay mineral, mainlyincluding andreattite and goeschwitzite. The mineral contents of quartz, feldspar and carbonateare low. Reservoir lithology mainly covers grain layered clay rock (shale), grain layer silty clayrocks (shale). Reservoir porosity distribution is3.21%~3.21%, with an average of4.5%.Matrix permeability rates are (0.004~0.219)×10-3μm2, with an average of0.053×10-3μm2.Organic matter pores are relatively less development.(3) Kerogen type are mainlyⅠand Ⅱ1; The organic matter evolution is of a mature-highmature degree. The main distribution of Ro between0.5%-1.1%, obvious trend of oilgenerative; the southwest is higher. The total organic carbon content of the study area is high,TOC of91%samples are higher than2%,with an average of4.15%.(4) From the comprehensive study, obtained shale reservoirs requirements of the studyarea: total organic carbon content TOC>2%, optimum TOC>4%, the thermal maturity Ro>0.9,shale effectivethickness H>15m.Combine with thermal maturity，total organic carbon contentand shale effectivethickness of the study area, predict favorable shale gas exploration area. |
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