Research On Volcanic Rock Lithofacies In Kalagang Formation Of Alang Sag Of Santanghu Basin

In this paper, the core and rock slice as the foundation of all the work for theresearch of the Kalagang formation lithofacies in the Malang sag of Santanghu basin,make sure that the geological is the evidence of everything,do further research aroundgeological theory.So,at first, do research on the core,and give a detailed description.Meanwhile,identificate the slice by use of microscopy technology,and study thelithology of Kalagang formation deeply,summarize the volcanic lithologic features,onthe basis of the lithologic features,compare the logging and seismic data to study thevolcanic rock lithofacies.The volcanic rocks features are obtained,and depicting thelithofacies distribution features in detail,this paper enriched the volcanic lithofaceisknowledge and provide theoretical support for reservoir prediction and development.Through the research we can know that by use of slice identification,coreobservation and logging identification,the Kalagang formation in Malang sag developslava and pyroclastic rock,concluding36kinds of specific rocks,such as basalt,andesiteand part of intermediate-basic transition rocks,the mainly type is generalized basaltrock.By combining logging and seismic,volcanic lithofacies can be divided into5categories and8subfacies.The result shows that effusive facies is the main lithofacies inthe study area.Different volcanic rocks have different logging and seismic features, byuse of these various response characteristics,combined with the lithology,can identifylithofacies.For obtaining the common characteristics of volcanic lithofacies, lithofaciesof every wells in the whole area are divided,and analysis the lithofacies of single well,Inorder to explore the formation between wells,selecting proper wells to do profileresearch,and work out the connecting-well lithofacies in profile.By using the providedconclusion before,then make a comprehensive analysis and evaluation,depicting theplane distribution characteristics of different times of Kalagang information.Inprofile,volcanic lithofacies include3kinds:explosion-effusive-sedimentation,effusive-sedimentation, effusive-explosion-sedimentation.The planephasing showsexplosion facies is mainly concentrated in the vicinity of the crater,distributing asbeads-strings along main fracture.Excessive facies is distributed in the lateral ofexplosion facies along the fracture,volcanic sedimentary facies mainly distributes in thesubsags and low-lying area of volcanic institutions.