| In view of the current prospecting and research conditions in Kongque River area of Tarim basin, the thesis,which makes full use of the present materials of physico-chemical prospecting, drilling and comprehensiveresearch as well as apply new theories, technologies and methods of petroleum geology, basin structuralanalysis, sedimentology, sequence stratigraphy, etc., make an in-depth study on the regional tectonicbackground, basic oil geological conditions, structural characteristics and sediment characteristics, etc., ofKunque River regions. Meanwhile, it also probes into the oil and gas reserve formation pattern by combingwith achievements on hydrocarbon source rock research, the main results was follows as:1. based on a great deal of fieldwork, drilling analysis and comprehensive interpretation of seism,proceeding from the regional tectonic background, the present and structural layout and combining withregional basin-mountain connection as well as its dynamic characteristics, the author has reached aconclusion that the basin evolution, which has close relation with the orogenic process of south Tianshanmountains and tectonism process of Lukedage mountains, can be divided into seven stages.2. On the basis of the seismic reflection and geological materials, six non-integrating faces (Z/AnZ,∈/An∈,S/AnS,C/AnC,J/AnJ,and E/AnE) generated in this area and full analysis on its causes andcharacteristics is also involved.3. according to the balance section research, the present structural layout are generated under the jointacting forces of the following four tectonic deformation: ①fault from Sinian to mid-Ordovician stage andridge-depression structure of troughs alternating with horsts in NE direction;② the formation ofnose-uplift structure and reverse of fault in Caledon stage;③ a series of fracture structure in EW andNWW directions generated out of the Hercynian orogeny in mid-up Devonian era and a string of fracturefrom NNE to near SN direction formed in up-Permian era;④fracture tectonic of Era Paleozoic continuedto grow in Mesozoic era and fold formation in EW direction.4. through single drilling exploration and seismic facies studies, six seismic facies and eighteen subfaciesare carved out and clarified. Based on assessment of single-drilling sedimentation facies and comparisonwith adjacent drilling, the author conducted Sedimentographical research and concluded that the sedimentenvironment of the area has been transmitted continuously from carbonate rock of the marine facies of theCambrian system to fragmentary rock sedimentation of continental facies of Jurassic system with varioussedimentation facies.5. the contrastive results of oil and gas sources in the east of Tarim indicate that the associated gasdiscovered at present mainly originates from Cambrian system of down-Era Paleozoic to hydrocarbonsource rocks of the marine facies in down-Ordovician. The set of rocks have such characteristics as rapidmaturity at early stage and continuing burying. Currently, the hydrocarbon source rocks are generally atovermature phase (Ro accounts for more than 2%), and make it impossible to produce large amount ofkerogen pyrolysis gas. The natural gas and condensate oil discovered now are the pyrolysis product ofancient oil reserves.6. summing up the oil and gas reserve formation pattern in Kongque River area, the author considersCaledon-Hercynian orogeny is the period in which large scales of reserves formed in the east of Tarimaround Cambrian system and the center of Hydrocarbon formation at down-Ordovician. Since theIndo-Chinese epoch, on one hand, the hidden crude oil at early stage split under the down tectonic layer ofPaleozoic erathem , resulting in the adjustment and transformation of ancient oil reserves in the swellingareas, and on the other hand, the tectonic layer of Mesozoic erathem received oil and gas provided bydown-Paleozoic erathem and formed reserves at late stage.
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