Research On Mud Logging Evaluation Technology For Deep Gas Zone In JiYang Depression

Along with the fast development of the world economy , the demands for hydrocarbon resources are increasing day after day,conventional exploration activities can't meets the demands for development of the world economy,and unconventional exploration activities are imperative under the situation,so exploiting deep hydrocarbon resources has been one of the paths that many countries amplify their hydrocarbon yield and reserves.in Recent Years,there are some breakthroughs in prospecting for deep cracked gas and coal-formed gas in ShengLi oilfield,the deep gas reservoirs exploration shows a well prospect,in future it's one of the important exploratory orientations in ShengLi oilfield.Because of oil quality of the deep gas being very slight,easily volatile,are some obvious differences with mud logging data of the conventional hydrocarbon reservoir,it is of stronger particularity and concealment,and at present the deep gas wells are less,degree of exploration is lower,so it is more difficult to make use of conventional evaluation technology to identify deep gas,and it is very necessary for according to characteristics of the deep gas's geology,engineering and mud logging to research mud logging evaluation technology for deep gas zone.Combined with geology data,testing date and drilled data,the wells deeper than 3500m are analyzed,which testing results are gas layer,and the wells belonging to the same block or having similar geologic characteristic and geologic position also are analyzed in this thesis,which comprehensive interpretations are gas layer or probable gas layer,or which testing results are not gas layer.Acorrding to above all data,the deep gas wells have been discovered to mainly centralize in four areas:the deep zone under salt structure in Northern Dongying Sag;Yi115 synclinal structure belt in Bonan subsag;the coal-formed Gas zone in Gubei low-buried hill;the deep zone in Lijin subsag.Acorrding to NMR mud logging parameters and the information from T2 spectrum,this thesis established the methods applying NMR mud logging data to reservoir identification and reservoir property evaluation , realized site reservoir property quantitative evaluation,assured the lower limitation of producing formation of deep gas zone's NMR reservoir property;analysed response characteristics of the different mud logging data on the deep gas zone basing on reservoir property evaluation,and concluded appropriate evaluation parameters of the deep gas zone;correction methods of partial influential factors of mud logging data are researched,established correction methods of the appropriate evaluation parameters of gas logging,cutting head space gas,NMR logging and the methods for identifying deep gas zone;basing on above all analysis combining with relevant evaluation example,established evaluation program of the deep gas zone,evaluation charts and standard of the parameters.All these work provided credible data source and reference for later geologic research,and further advanced level of the mud logging evaluation technology.