| The BQ67 block of Xinzhuang oil field is a small complex fault block (fault-nose) heavy oil reservoir which is sheltered from faults, and structurally located in the sag part of Biyang, the northern slopes and eastern Xinzhuang various fault areas, lying in the the intersection of northeast central faults which aheads toward north and south. It grows fragmentally and the construction is in segments. The oil layer is mainly dispersed over Member 3 of the Hetaoyuan Formation the lower Tertiary , and is controlled by structure, faults and sand. Since this department construction as well as the lateral tracing comparison and division of the single sand level is hardly researchable, and sand distribution is not distinct, the relationship of oil-water layer and the varying rules of various oil-water layers can be vaguely recognised. This has led to a limitation of the exploitation of the oil field.This essay, aiming at the existence of the oil pool and having weaved a structural map which has a 10m contour interval in combination with the predecessors' explanation about earthquake, believes the research region should locate on the nose structure which uplifts itself from southwest to northwest where there are some positive-negative direction microstructure types such as nose shaped uplift, small fault blocks and gain grooves etc.; Basing on the predecessors' thin-layer division and combining the contrast analysis of well logging data, the BQ67 well is chosen as a standard well and the connecting-well section which can cover the whole region is constructed then, regarding the lithology curve as a major contrast and dividing foundation, meanwhile referencing to the electric property curve (line derived from points, south towards north), finally the subdivision contrasts of more than 80 wells within the region are completed, indicating that the stratum of the research region is transmeridionally stable with a lower south part and higher north part and the stratum connexity is mainly altered by faults; The analysis of core facies- log facies indicates that the reservoir mainly developed from the underwater distributary channel and the estuary dam sandbodies of the near-source fan-deltaic front, and the research region sedimentary facies model is also constructed; reservoir sand bodies is continuous in plane, and has a vertically large quantity with small thickness. Mercury intrusion tests have shown that the reservoir is mainly macropore path and moderate sorting, the pore types are mainly intergranular pores and dissolved pores which belong to the moderate pore and higher permeability reservoir. On the base of rock core physical properties, after establishing the neural network model, the physical parameters of over 80 wells within the region are interpreted and the plane distributive maps of every single layer of physical parameters are weaved; The cross plot, multiple stepwise discrimination method and BP neural network method are comprehensively applied for identifying oil-water bed. Advantageous blocks and single sand layers are preferably selected after a comprehensive reservoir evaluation based on an integration of each parameters. In general, the study formation has well physical properties and large oil-bearing area. Moreover, it is mainly distributed around the faults, advantageous blocks are concentrating mainly in the high position which is sealed by faults. The researched four small layer are all favorable reservoirs, and the best single ones are III4~1,III4~3,III5~4,III7~1.
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