Research On The Comprehensive Evaluation Of Favorable Reservoir On North Slope Of Fuxin's Upwelling Area

Fuxin uplift zone is a key exploration appraisal area for Jilin Oilfield Company,whose north slope lies in the converging area of Qijia-Gulong sag and Sanzhao depression. And in west and south it links with Changling sag, and in east with Dong-nan uplift. Since the commercial oil is successfully tapped in Sep 29th,1959, a number of oilfields including Xinmin, Xinmiao,Xinli,Mutou have been discovered, where oil is mainly produced from Fuyang Oil layer,namely, Member3 or Member4 of Quantou Group in lower Cretaceous formation,which are dominated by lithologic reservoir and fault-lithologic reservoir, with proved oil in place of 47 804×10~4 tons.On the basis of geologic data, coring data, logging data and well testing data,supported by the principle of sedimentology, reservoir geology, logging geology and development geology, an integral study in respect of sequence-stratigraphic study, sedimentary microfacies analysis and comprehensive prediction of hydrocarbon accumulation is conducted. It indicates that the oil-gas pool forming in study area depends on its lithology,characterized by great varance of petrophysical property and strong heterogeneity. According to predecessor's achievements and systemetic study on north slope of Fuxin Uplift, the favorable reservoir distribution regularities is identified and favorable accumulation area is predicted. This results points out that the resource area in this study area lies in its south, controlled by Changchun water system, so it's classified as flural-delta facies in consideration of sedimentary type, and belong to low-porosity low permeability or ultra low permability structure in terms of pore space.The controlling factor affecting petrophysical property is analysed from micro and macro angle. It is summarized production potential is mainly concerned with lithology, petrophysics and micro pore structure. These achievements have been widely used in the appraisal of controllable predicted reserve, laying a good foundation for future well placement and reserve arrangement.