The Research On Hydcocarbon Enrichment Regularity Of Chang 2 Oil-bearing Formation In Jiyuan Oil Field

Jiyuan oilfield is located in Yishan slope of Ordos Basin in the middle west, in order to carry out more reasonable and effective in the future work of exploration and development, this paper selects in Jiyuan area, Yanchang reservoir as the main object of study, on the basis of a large number of core, logging, logging data analysis, the structural characteristics, stratigraphic characteristics, sedimentary facies characteristics, storage reservoir and reservoir characteristics of the fine, according to the research and the analysis.Research results show that of Yanchang group in delta front underwater diversion channel sand body in the plane composite contiguous to become oil gas lateral migration and gathering places. Source reservoir cap combination of development, with the superior geological conditions for hydrocarbon accumulation, long 2 delta plain distributary channel sand body is the main reservoir sand body, the work area central Ji Yuan- Fanxue area row like nose is relatively dense. Reservoir sand body is mainly fine-grained feldspar sandstone and lithic arkose, grain coating chlorite cementation and dissolution of feldspar in the storage space is an important and constructive role, mainly developed feldspar dissolution phase and grain coating chlorite cementation phase. Reservoir in the vertical to the distribution has obvious difference, to Chang213 layer is the most abundant, to upper and lower layers of the degradation, in the plane reservoir vast most distribution in the high part of the structure, and for Chang213, Chang221 layer reservoir has obvious things into a row features, and Chang211, 212 and 13 layer into North and South with the characteristics of relatively more obvious, and long 23 oil reservoir were scattered like.Through the detailed analysis of reservoir forming conditions, the formation and distribution of reservoir in the study area are controlled by sedimentary facies, reservoir area, regional cap layer, and nasal structure. Among them, the effect of nasal swelling in the whole study area is weak. Favorable configuration and combination of various factors to make the oil and gas accumulation, into the reservoir.