Reservoir Evaluation And Favorable Regions Prediction Of The Chang-2 Oil Formation In The South Of Hao Jiaping,Ansai Area

The south of Hao jiaping,Ansai area is located in the east-central of ordos basin Yishan slope,which exploration area amount to 240km2,Chang 2 formation is one of the main development reservoir in research area.Due to the weak fundamental geological research in the early,the drilling Wells in the shouth is less,it still faces the problems,such as the confusion in stratigraphic classification,sedimentary facies and sand body distribution characteristics is unclear,reservoir evaluation is incomplete,by conducting reservoir comprehensive evaluation and favorable area prediction research,provides certain geological theoretical foundation for the next exploration and development in the study area.This paper is guide to sedimentary petrology,petroleum geology,reservoir geology and multidisciplinary theory,using the results of previous studies and neighboring areas,Combine with well drilling,logging,coring,laboratory analysis and other basic datas researched the study area systematic.The results shows that: the strata thickness changes stability,overall shows monoclinal structure while the east is high and west is low,develops nose-like uplift structure in partly;In Chang 2 period it belongs to delta plain sedimentary subfacies,mainly develops distributary channel,floodplains these two microfacies,the sand body is thicker in distributary channel,superimposed each other in vertically and connected in plane,it's the main reservoir sand bodies in the study area;The rock types are mainly feldspar sandstone,particle size is given priority to medium grained sandstone,the pore of residual intergranular and feldspar dissolved are the major reservoir space,physical characteristics shows that it's the low pore-extra low permeability reservoir and influenced by diagenesis greatly,results the plane and vertical heterogeneity is clear,the sensitivity is about water and salt.Comprehensive the above results,use the reservoir evaluation standard to classify them,ultimately according to the tectonic characteristics,sedimentary facies and the distribution of sand body pattern,production performance,well logging interpretation and other aspects predicted the favorable regions,finally selected out eight built production target areas,including two type?regions,five type ? regions,one type ? region,the total acreage of all favorable areas is about 58.8 km2.type?and type? are the key of the future exploration,type ? is the oil and gas prospect district.