| The central block 1 Jurassic System is lower degree of exploration areas in Junggar Basin. Asthe incessant exploration and realization to this block, the major exploration target becomes moreand more specific. Current research shows that: The trap style of Jurassic System is not a simpletrap controlled by single low-structural-closure anticline, fault or lithology, but a subtlecompound trap controlled by above mentioned multi controlling factors. Although severalexploratory wells has oil and gas show in Sangonghe group Jurassic System, there are still manyproblems to solve urgently. The recognition and description to subtle traps and the accuracy ofprediction to target traps' oil and gas content is far from enough. It's necessary to further improvethe seismic techniques for recognition and description to this kind of trap and sum up a set ofexploratory techniques and measures for the complicated seismic geology condition and trapcharacteristics, such as big cover-depth, low structural closure, anisotropy reservoir etc. Bymeans of research to this area, the author proposes a study discipline: on the basis of the analysisto lithologic trap development traits and under the guide of capacity analysis to resolvinggeologic problem through seismic data and geology mode, make trap recognition and descriptionby means of comprehensively applying the high resolution sequence stratigraphic subdivision, fine horizon calibration, seismic attribute analysis and log confining inversion. Besides, thisstudy disciplines make good effect to this area's exploration.Key techniques used in thesis study:①high accuracy horizon calibration technique: carryon fine horizon calibration research via comprehensively apply the drilling, logging, seismicvelocity data etc.②sequence stratigraphy study: carry on the study of Jurassic sediment andevolvement, confirm the good facies for subtle trap development and distribution, and strengthenthe guidance of sequence stratigraphy toward seismic data interpretation.③seismic forwardstudy: Study the seismic response traits of all kinds of geologic objects by seismic simulation, sothat provide foundations to complex traps' search and recognition.④seismic particularprocessing study: Process the lines which control the favorite target block by means of seismicattribute extraction and seismic inversion, so that improve the trap recognition and reservoirprediction.⑤fine interpretation to high resolution data and trap recognition technique: Make fulluse of 2D and 3D seismic data, on the basis of fine stratum calibration, comprehensively useseismic forward solution, inversion and seismic attribute analysis, carry on the structure andsubtle trap interpretation to seismic data, and recognize subtle traps effectively.⑥reservoirprediction technique: on the basis of stratigraphic subdivision and correlation, sediment facestyle, sediment evolution traits' study, analyze the sediment face style and sediment faciesdistribution characteristics, optimize the reservoir anticipation method and forecasting thereservoirs laterally.⑦trap evaluation and target prospects optimization: According to trap evaluation, optimize favorite traps and make proposal for well deployment.Study results:(1) Aiming at the actual seismic and geologic condition in central block 1, confirm thebasic requirements to seismic data processing in subtle hydrocarbon reservoirexploration; analyze the major traits of this area's seismic data; form a set of effectivehigh resolution processing techniques: With the spirit of innovation, make use of someimportant techniques, such as static correction, velocity analysis, amplitude andfrequency compensation, deconvolution, noise attenuation, stacking, migration imagingetc. Carry on the processing method research, so that form a high resolution processingflow. After the fine static correction, a serious static correction problem is resolved.Take true amplitude preserve process and effective high resolution method, relative highresolution and S/N seismic profile is got. Each sets of stratum of this profile have clearwave group characters and good migration effect. The effective wave's dominantfrequency of Jurassic target stratum in final seismic profile has reached to 45～60Hz, which enhance the ability to solve geologic problems through seismic data, and is alsohelpful for seismic data's structural interpretation of subtle hydrocarbon reservoirs, sequence stratigraphic analysis and seismic reservoir prediction and evaluation.(2) Subject to related questions' research progression, carry on fine stratum division tosectionⅡof Sangonghe group Jurassic, which is further divided into several short-termstratum sedimentary cycle through regional stratigraphic correlation traits andsedimentary cycle analysis and then make fine layer contrast. On this basis, analyze allkinds of class attribute's slices, study reservoir's spatial variation by using lamella'sseismic attributes differences, and carry on the reservoir parameters' forecast study inintervalⅡof Sangonghe group in 3D connected projects by using seismic attributesinformation, so that sedimentary system of major exploratory stratums in this area isconfirmed.(3) Trap recognition and description techniques series with pertinency are established: Onthe basis of regional comprehensive evaluation, under the guideline of capacity analysisto resolving geologic problem through seismic data and sequence stratigraphy theory, combine with single-well's geophysical characteristics analysis, comprehensively usegeophysical techniques to carry on the fine portray to subtle traps, such as fine stratumcalibration, fine structural interpretation, forward solution simulation, log confinedinversion, seismic attributes extraction and analysis, spectrum analysis etc. Subtle traprecognition and description technique series under the guidance of geologic mode areestablished, so that subtle traps are found and exploration makes great progress.Innovation is made especially in the fields of prestack AVO P-wave and S-wavecombined inversion information to identify deep lithologic and oil and gas beatingobjects.(4) Processing-interpretation integration platform is established: On the basis offundamental data analysis and staggered method study result, aiming at specific geologic assignment, carry on repeated combination between processing andinterpretation; with the core of exploratory object, on the basis of processing, under theguidance of interpretation, strengthen the combination of geophysical prospecting andgeology and realize the processing-interpretation integration comprehensive study.(5) Carry on the application study on AVO technique. On one hand, use AVO attributessection to find attributes abnormity body, then distinguish its oil and gas bearing; on theother hand, making use of velocity data provided by AVO, carry on elastic impedanceinversion, identify the distribution of effective reservoirs, and distinguish its oil and gasbearing through P-wave and S-wave inversion. Finish the connected projects 3D AVOspecial processing in Moxizhuang, Zhuangdongbei, Central block 1, on the basis ofAVO attributes analysis, carry on AVO P-wave and S-wave impedance inversion, studythe distribution of effective reservoir by using fluid impedance data, which providesfoundation to exploratory targets.(6) Research result combines with production closely and directs the exploration effectively.Well locations mentioned in this thesis gain different-degreed oil and gas show. Highdiscovery well ratio is made in such a high-risk area, which gains great economy andsociety effect.
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