【摘要】 目的区分古代富泥低弯度河流与曲流河,总结其沉积特征和河道砂岩的展布,为储层描述和预测提供参考。方法从不同盆地和时代的三维地震资料中识别出非辫状河也非曲流河的古代低弯度河道的展布与延伸,比较其河道(带)与漫滩的沉积差异及其与其他类型河流沉积的异同。结果从三维地震资料中获得了古代富泥低弯度河沉积的一些共同特征:古代富泥低弯度河多发育在干旱气候条件下的冲积扇扇缘和扇外;平面上可呈单河道体系,也可呈分支、交叉的多河道体系;单河道砂体规模小,一般仅数米厚;宽厚比小。结论三维地震识别出的低弯度河道一般为多期河道砂体相对发育的河道带。更多还原

【Abstract】 Aim Ancient mud-rich low-sinuosity rivers are summarized and separated from meandering river so as to understand exactly the relative depositional characteristics and channel sandstone distribution.Insight into the mud-rich low-sinuosity rivers can help for reservoir characterization and prediction.Methods The distributing and extension of ancient low-sinuosity channel can be identified from 3-D seismic data.They are neither braided river nor meandering rivers.The characteristics of channel belts are compared with overbanks,and compared with deposition of other types of rivers in different basin and different geologic times.Results The common depositional characteristics of ancient mud-rich low-sinuosity river are realized:Ancient mud-rich low-sinuosity rivers are invariably developed in lower fan and frontier fan environment of dry climate.They are planar either mono-channel system or multi-channel system that braches or cross each other.A mono-channel sandbody is usually several-meter thick and small in scale and width-thickness ration.Conclusion Ancient mud-rich low-sinuosity channels identified from 3-D seismic data are possibly a river belt in which multi-phase channel sands likely deposited.更多还原