| The research object of this thesis is chang6 reservoir of HuaQing area.Firstly,I study previous research results of the study area carefully.Based on core analysis and outcrop observation,I analyse regional geological background and depositional setting and make the stratigraphic division and coenocorrelation of chang 6 with the methods and theories of sedimentary,logging geology,reservoir geology and other theories.Secondly,I summarize the petrological characteristics and pore structure characteristics as well as the facies marks.Meanwhile,I has carried on sedimentary microfacies division.Through the analysis of drilling and logging data,combining with the casting thin sections,X-ray diffraction,and other testing technology,the paper describes the characteristics of diagenesis and diagenetic facies,analyses the influence of various types of diagenesis on reservoir concretely.The research suggests that the formation is stable overall and the change of its thickness do not chang severely.The study area has been identified as delta-gravity flow deposition system with developed large areas and thick layer sand bodies.The types of the sandstone in research area are mainly lithic arkose and feldspathic litharenite and the maturity of the sandstone is low.Meanwhile,extural maturity of sandstone is medium and diagenetic grade is high.Secondly,rock debris composition and interstitial material are both very complex in this ares and.Thirdly,pore types mainly include intergranular pore and feldspar dissolved pore.Besides,it has large plane porosity.Fourthly,this reservoir,typical low porous,low and ultra-low permeable,high degree of heterogeneity,has good correlation of petrophysical properties.Lastly,the mainly reason of low porosity is compaction and cementation,but chlorite cementation is good for petrophysical properties and dissolution,happening in cleavage and crack caused by compaction.The main reservoir type of chang63 is ? a and ? b in research area. |
PDF Full Text Request