The Classification And Evaluation Of Yan9Reservoir In Z Area Of Ordos Basin

Yan9reservoir is a typical low permeability oil layer in Z Area of Ordos Basin, Currently, the major oil layer of Yan9is in high water cut stage, and it is difficult to develop. Therefore, research of reservoir classification evaluation needs to be carried out, and the development of technology policy making was serviced in the following step. In this paper, neural network technology is used to the reservoir classification evaluation. Thereby, the effect of reservoir classification evaluation is improved.The main research object of this paper is yan9reservoir of Z Area in Ordos Basin. Based on the geological data、core data、logging data and the production dynamic information of study area, the research of stratigraphic classification and correlation, the sand top micro-structural features of small layer, sand thickness distribution characteristics, the sedimentary micro-facies of small layer, four characters relationship, reservoir heterogeneity characteristics, reservoir parameters distribution characteristics, reservoir classification evaluation, and so on is carrien out.The research shows that in the study area Yan9strata can be divided into the Yan91, Yan92, Yan93. The whole sand body of each small layer is more developmental, and sand thickness is bigger, and the sand body ductility is better. The distribution of sand bodies’ presents stripped along with the northwest to southeast. The central region of the reservoir is slightly thicker, good general connectivity on the plane. Northwest region is nearby to the material source, and its sand body distribute widely. Sand bodies distribute narrowly and presents moniliform in sourtheast In each small layer, the sand bodies of Yan93are thicker, better oil-bearing, and it is the major oil layer. The overall trend of small layer sand top micro-structure presents west-dipping monocline, and presents nose slot combination on the plane. Sand top micro structure of the small layer presents certain inheritance and difference. The whole structure of the region is simple and some areas presents low amplitude uplift like nose. The sedimentary facies of the study area is delta plain sedimentary, and the main sedimentary microfacies are distributary channel, natural levee and river diffuse swamp. The direction of the watercourseshe is northwest to the southeast, The research of four characters relationship shows that the lithology of the study area decides physical properties andHydrocarbon, certain electrical characteristics was performanced, we can analyze and revealthe lithology, physical property and hydrocarbon potential according to electrical. Theresearch of heterogeneity shows that interlaminar heterogeneity of Yan92is the most serious,and Yan91take second place.The research of the reservoir plane distribution shows that theflat distribution of reservoir is significantly effected by the structure, sedimentary microfaciesand reservoir heterogeneity. Along with the watercourse, the distribution of reservoir is moreconcentrated. Finally, under the guidance of the sedimentology,rock stratigraphy, geostatisticstheory, the reservoir classification evaluation of the study area is done by combining theconventional reservoirs classification method and neural network technology, and the researchof the favorable areas prediction is carried out. Thus, the purpose of quantitatively identifyingreservoir category can be achieved effectively.At the same time; the accuracy of theidentification mode is high. And its practical applicability is very good. The classificationidentification model which is built based on identification model is not only convenient for theprocessing of computer programming, but also easy and simple. It provides a good platformfor large sum data processing of the unconventional reservoir. The results of this researchprovide significant geological foundation for the development of the next production plan ofthis area.