| Yanqi basin is among Tarim basin, Junggar basin and Turpan basin, lying in the east of Tianshan drape zone It is a Mosozoic and Cenozoic coal basin growing from Haixi drape base and its area is 13000km2. The basin takes on a layout of two depressions and one uplift. From south to north the basin has three No. I tectonic units named respectively: Bohu depression, Yanqi uplift and Hejing uplift. Sediment cover consists of Trias, Jurassic, Tertiary and Qaternary, but Jurassic is the mainly exploited stratum. Henan oil field started to cosmically exploit in September in 1993 and fond two oil fields(Biaoliang oil field and Bengbutu oil field) and four oiliness sections(Baobei, Baozhong.Bengbutu and Bengbutudong), the whole area of oiliness come to 23.5×104t, discoverable geologic reserves of oil come to 4172×104t, produce ability of crude oil come to 23×104t, its accumulation output of crude oil and gas respectively come to 122×104t and 3.4×108m3. These prove that Yanqi basin is not only a oil-gas basin, but a preferable enrichment, containing oil and gas and preferable exploited foreground basin. Since the exploration in the basin for 10 years, We have got great many geologic data when we obtain breakout and finds. On these base, the study on forming condition and distribution rule of oil and gas has great meaning on summarizing geologic rule of forming- hydrocarbon and pool-forming of these small basin containing coal and on the further exploited work of Yanqi basin. With the guide of modern petroleum geologic rule, insisting the thought of integer, dynamic and integration, carrying through forming-basin, forming-hydrocarbon and pool-forming and being established in the characteristic of reformed basin, high ground temperature grads, coal stratum forming hydrocarbon, using the appraise thought of petroleum pool-forming system of relict basin, using comeback of balance profile and many new technology of testing, studying on each element and interrelation in the course of forming-hydrocarbon and pool-forming and analyzing main controlling factor and oil-gas distribution rule, we obtain viewpoint and conclusion as follow:1.On the analysis of region geology ground, we lodge that the formation and evolvement of the basin have consanguineous relation with the evolvement of Tianshan tectonic. Bestriding over Tianshan tectonic belt of different tectonic property and evolvement and Kuluketage causes that its structure and tectonic evolvement are clearly controlled by base tectonic and forms the deep structure character of belt form south to north with a boundary of Yanqi fracture. Northern base of the basin belongs to southern Tianshan tectonic zone, consists of large number of midd- Devonian and Haixi granite and is a passive continent verge depression. The southern base consists of Kuluketage stratum, mainly including foresinian crystal base and notamorphismless stratum of Paleozoic.2.studying on the tectonic conformation in the base, we expound that the main tectonics consist of near E-W extrusion tectonic zone and N-W conversion tectonic zone in basin and tectonic transmutation take on diamond tectonic layout with forming trap from south to north and forming block from East to west. On the basis of comeback analysis of tectonic and combining with regional tectonic background in basin, we can divide evolvement of Yanqi basin in Mesozoic and Cenozoic into three main phases, that is to say weak extension in early and mid-Yanshan, strong extrusion in late Yanshan and forming phase of thrust in Xishan.3.The study on sediment and sequence strata, sediment veneer in Yanqi basin consist of Trias, Jurassic, Tertiary and Qaternary, the Jurassic coal oddment rock system is the main exploited strata. The Jurassic strata can be divided into three sequences of bride rive-delta, meandring rive- shallow lake and lake- delta. Each sequence can be divided into LST, EST and HST wich show the representative sequence-system in the depression in Jurassic.4.The analysis of thermal history and palaeogeothermal in basin shows that the the...
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