Study On The Reservoir Geologic Model Of Dainan Formation In Lianxi Area Of Subei Basin

The reservoirs in Lianxi of Subei Basin are structure and lithology controlled reservoirs. The structures and fracture system are complicated and the fault distribution and combination rule is not clear in Lianxi area. The sand body, which is mostly controlledby lithology, has complexdistribution regularity, greatly changed Vertical and horizontal,poor reservoir property and Serious reservoir heterogeneity. Although we have carried out some research work in recent years, but still not system, not enough depth, and not to carry out the system of reservoir description and comprehensive research in aspects of effective development technology. To solve above problems, we explain the main structure at the top of the formation through fine stratigraphic correlation in Lianxi area, at the same time of reservoir sedimentary microfacies and sand body distribution rule to do in-depth research, Focusing on the analysis of reservoir heterogeneity. At last, weestablish the fine 3D geological model of Lianxi area, In order to further strengthen the study area provide reliable geological basis for development adjustment.Through the study, the following results were obtained:(1) The stratigraphic framework is establishedin Lianxi area. After the fine stratigraphic division and correlation, database of strata classification, sandbody and breakpoint of local wells has been adjusted. After the fine single correlation, the E1d25 Fm. has been dividedinto 19 single sand bodies, include eight main oil sands.(2)The structure features of Lianxi area wereclarified,clarified the tectonic framework and ran the fine structure interpretation.(3)The main sandbody growth rule of Lianxi area was found. Combined with the model of control sand geological permeability reservoir effective thickness to analyze plane distribution of Lianxi area permeability sandstone and developmental situation, we redraw the sedimentary microfacies of the single sand body and reveals the main sand body of Lianxi area growth rule.(4)The reservoir characteristics of Lianxi area areclarified. By analyzingthe reservoir property and heterogeneity, the results suggest that the reservoirs of Lianxi area are low porosity, low permeability reservoirs. The underwater distributary channel shows medium heterogeneity, and the excessive shore sand body shows strong heterogeneity, which interlayer and plane heterogeneity is serious.(5)Explored the tructure and lithology reservoir modeling accuracy improvement method. The pinch, interlayer, and the NTG model processing method were mainly studied.(6)The fine 3D geological model was established. Structure model and property model and sedimentary microfacies model has good consistency, with actual situation in line with the reservoir geological model, which has high credibility.Through the research, the fine 3D geological model of Lianxi area was established., effectively guided the adjustment of Lianxi area. The effect is remark able after adjustment, the daily oil of Lianxi area has been raised from 9.0 t/d(end of 2009) up to 104.0 t/d(Mar. 2014).