The Gudong oil field offers a unique opportunity to characterize thin meander-belt sandstones in an area with a dense network of wells (100 wells per square kilometer or 259 wells per square mile). The goal of this study is to evaluate the evolution of subsurface meander-belt complexes through analysis of their overall stratigraphic architecture defined by the spatial distribution of sedimentary structures and stratigraphic surfaces of stacked point-bar sandstones, which severely affect the potential for producing the remaining oil in these mature oil fields. Five types of superposition structures, which reflect the shapes of the point-bar sand bodies in the superimposed regions between point bars, are identified by combining stacked and migrated seismic profiles, seismic forward models, and wire-line log profiles. The point bars belong to different stages of channel stories through the analysis of their superimposed structures and the vertical offset of the basal surfaces of point-bar sandstones. Five channel stories are recognized in the thin meander belt. They can be distinguished by the analyses of stratal slices, wire-line log profiles, and tracer data. These channel stories were found to exhibit unique morphometric characteristics: the thickness and width of the channel stories changed with the discharge of the paleoriver; the widths of the later channel stories became more stable through time and were not affected by the flow discharge during the deposition of the channel stories. The identified superimposed structures between subsequent point bars and morphometric parameters of channel stories are useful for the modeling of the target reservoir.

中文翻译：

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地下曲流带砂岩的构造分析——以渤海湾盆地东部沾化凹陷致密油田为例

古东油田提供了一个独特的机会，可以在井网密集的地区（每平方公里 100 口井或每平方英里 259 口井）表征薄曲流带砂岩。本研究的目的是通过分析由沉积结构和堆积点砂岩地层表面的空间分布定义的整体地层结构来评估地下曲流带复合体的演化，这严重影响了剩余的生产潜力。这些成熟油田的石油。结合叠加偏移地震剖面、地震正演模型和测井测井剖面，识别出反映点坝叠合区点坝砂体形态的5种叠合构造。通过对点坝叠合构造和点坝砂岩基面垂向偏移的分析，点坝属于河道层的不同阶段。在细长的曲流带中识别出五个渠道故事。它们可以通过对地层切片、电缆测井剖面和示踪数据的分析加以区分。发现这些渠道故事表现出独特的形态特征：渠道故事的厚度和宽度随着古河流的排放而变化；后期河道层的宽度随着时间的推移变得更加稳定，并且不受河道层沉积过程中流量的影响。识别出的后续点杆之间的叠加结构和渠道层的形态测量参数对于目标储层的建模很有用。