Diagenetic Facies of Xujiahe Formation Member 4 Reservoir in Jinqiu Area and the Logging Recognition

The diagenesis,diagenetic minerals,diagenetic stage and diagenetic evolution sequence of Xujiahe Formation Member 4 reservoir in Jinqiu Area are studied by the normal thin sections,casting thin sections,X-ray diffraction scanning electron microscope analysis data. Five types of diagenetic facies are divided based on diagenesis,diagenetic minerals and its impact on reservoir property:compaction tight facies,carbonate cementation tight facies,illite and montmorillonite mixed layer filling facies,corrosion of unstable components facies and chlorite mat cementation facies. A series of logging curves including compensated neutron logging,density logging,natural gamma ray,array induction log and spectral gamma-ray log,are sensitive to the diagenetic facies. Actual log data of Well Jin1 were processed with the built logging identification model,and the vertical distribution law of diagenetic facies in Well Jin1 is figured out by the well logging data. When the logging recognition result of diagenetic facies in Well Jin 1 is corresponded with the reservoir physical property analysis data,it is found that the layer with the corrosion of unstable components facies and chlorite mat cementation diagenetic facies are the best,while the compaction tight facies illite and montmorillonite mixed layer filling facies are relatively worse,the reservoir property of the carbonate cementation tight diagenetic facies are the worst.