Distribution prediction and evaluation of the favorable res ervoir zones of lower section of Xingouzui formation in Mawangmiao region,Jianghan oilfield

The lower section of Xingouzui formation in Mawangmiao region has good oil and gas accumulation geo logical conditions,and its lithology,diagenesis and sand body,sedimentary micro-facies and other factors control the distribution of favorable reservoir zones of lower section of Xingouzui formation in this area.Through statistical anal ysis of various controlling factors,we established the criteri on for classified evaluating the relationship between various controlling factors and reservoir development.Combined with the composite evaluation results,we compiled the dis tribution prediction maps of the favorable reservoir zones of each oil group with the oil group as a unit,and effectively predicted the favorable reservoir zones of lower section of Xingouzui formation in this area.Studies show that Class Ⅰ and Class Ⅱ reservoirs developed widely for lower oil group Ⅲ in Xingouzui Formation of Mawangmiao area during the reservoir development of oil group Ⅲ,but Class Ⅲ reser-voirs seldom developed;Class Ⅰ and Class Ⅱ reservoirs devel oped more widely mainly in the eastern part and minor in the western part during the reservoir development of oil group Ⅱ,while the developing area of Class Ⅲ reservoirs is small;Class Ⅰ reservoirs developed only in the area of Well Yuecan 2-Well Ban 7 in the northeast corner of the study area dur-ing the reservoir development of oil group Ⅰ,while Class Ⅲ reservoirs relatively developed compared with the reservoir development of other two oil groups.