Reservoir Architecture Analysis Of Meandering River: A Case Study Of Upper Guantao Formation,West 7^th Block,Gudong Oilfield

This paper is aiming at the meandering river reservoir of the upper member of Guantao Formation of the west 7th block of Gudong oilfield,integratedly combined with seismic,well logging,analysis of the core,dense well pattern and the static and dynamic material,basing on the method of “hierarchical constraint,model fitting,multidimensional interaction”,studies the architecture characterization of meandering river reservoir.Based on the fine isochronal strata framework,studying on the complex sedimentary micro facies,expounding and dividing the single meander belt,studying on the architecture characterization of the inter of the point bar.The studies show that:(1)The stratigraphic patterns contain accretion nearly the same thick in vertical in the target strata,and local strata increases the thick because of the channel incision;(2)The 5th sand groups of the Guantao Formation are whole in the rising sedimentary stage in the metaphase-cycles base level,transiting from the brained river sediments to meandering river sediments,and mainly being as the meandering river sediments.It contains four architectural factors of channel,overbank,abandoned channel and floodplain;(3)Complex sedimentary micro facies on the plane show as continuous,mixed,single and isolated distributary styles;(4)The major layer of the Ng522 contains the single meander belt sediment,with the height of 4-12 meters and the width of 500-2500 meters,and the longest span of the point bar can be as 1520 meters;(5)Lateral accretion sand bodies of the inter of the point bar distribute as horizontal echelon,with the height of 0.1-0.3 meters and a dip angle of about 3o-6o.The horizontal width of the single lateral accretion sand bodies is about 480 meters,and the horizontal interval of the contiguous lateral accretion bed is about 40-120 meters.