Study On Reservoir Heterogeneity And Interlayer Of The Lower Member Of Oficina Formation In The MPE-3 Block, Venezuela Basin

Study on the reservoir heterogeneity is a basic work in geological exploration and development of oilfield,which is the core of reservoir description.At present,the conventional reservoir heterogeneity research is developing towards the direction of quantification and refinement in the development of horizontal well in the region.In order to improve the level of well drilling rate,the quantitative characterization of interlayer is particularly important.In this study,the high permeability reservoirs which developed in the braided river delta of lower Oficina Formation in block MPE-3 of the Venezuelan Basin are taken as the main research section.The reservoir heterogeneity is studied by using the data of core,logging and so onThere are several conclusions in this study.(1)The reservoir of lower Oficina Formation mainly developed in composite heart beach bar,braided channel filling,crevasse splay,flood plains,channel inter;(2)The reservoir heterogeneity in the lower Oficina Formation is qualitatively evaluated.It is considered that the other 4 small layers are high porosity and high permeability reservoirs except the small O-11 S layer,and the overall heterogeneity is weak-medium;(3)The interlayer is a key factor affecting MPE-3 reservoir heterogeneity.The geological origin of the interlayer in the study area has been determined,barrier is mainly caused by flooding plain mudstone and interlayer is mainly developed in the splay,abandoned channel deposition or suspended sediment silting accretion;(4)The identification standard of interlayer in the study area was established.On this basis,the mud content curve is calculated by GR curve,and the shale content model is established by making full use of the data of the horizontal well.We determined the limit of a value which is used to be the distinction between the sand and shale,and established the 3D geological model of the interlayer based on sedimentary model-horizontal wells;(5)The main controlling factors affecting reservoir heterogeneity are determined,and the control effect of interlayer on remaining oil is revealed.