The Research On Favorable Areas Prediction Of Chang4+5Formation In Jingbian Eastern Area

This article to jingbian in eastern Ordos basin yanchang group chang4+5reservoirgroup as the research object, through177Wells in the area and formation accurate divisionand comparison, the first for long again on a small and the method of using combined cyclecontrol, thickness, through a small layer comparison of yanchang group in the studied area andits4+5small layer further comparison, the chang4+5reservoir can be divided into chang4+51, chang4+52two reservoir section from bottom to top. In combination with thesedimentary background in the study area, according to the rock types, sedimentary structure,sedimentary cycle, rock-electr combination of a variety of means, single well facies, thinkjingbian yan chang group chang4+5reservoir group are mainly delta sedimentary system,and further points delta plain subfacies. The study area is affected by the northeast provenance,river channel and distributary channel sand body is roughly north east, south west distribution,the reservoir in the study area paragraphs of sedimentary facies and sedimentary microfaciesdistribution has the characteristics of inheritance, and the various sedimentary period thandevelopment channel and distributary channel deposits.From the reservoir petrology features, physical properties and pore structure types, etc.,to extend the main oil layer yan chang group chang4+5reservoir was studied, the resultsshow that the eastern jingbian yanchang group4+5reservoir rock types mainly arkose, lithicarkose, the contact relationship is line contact,and ribbed roundness is subangular. Sedimentstructure maturity is high, the pore structure is intergranular pore, pore structure ischaracterized by mircropore throat type and it belongs to ultra-low permeable formation (Ⅲclass) and super-low permeable formation reservoir (Ⅳ class).Through the study of reservoir control factors that sedimentary facies is the basis for thecontrol of oil and gas distribution in the study area, nosing structure played an important rolein oil and gas enrichment.On the basis enrichment pattern studies of oil and gas，we canpredict the beneficial exploration region of Chang4+5stratum and provide geology referencesfor the future exploration at last.