应用遥感信息图像研究现代水下分流河道河流类型

Research on the channel pattern of present subaqueous distributary channel by remote sensing image

水下分流河道是三角洲前缘亚相最重要的微相类型及油气优质储层之一,但目前对水下分流河道河型研究较少,其是否存在曲流河型、辫状河型?有无其他河型?是否存在高角度转弯现象等问题尚不十分清楚,并直接影响高含水期及三次采油阶段水下分流河道单砂体精细刻画、内部构型或建筑结构、三维非均质性模式等研究,为此,弄清水下分流河道河型成为既急需又具有理论意义的关键问题。针对这一关键问题,以现代沉积为重要钥匙,采用能整体、细致揭示河道平面形态及特征的遥感信息法(卫星图像)对41条现代水下分流河道进行深入剖析,确定水下河型;将水下分流河道分为4带、划分3类8亚类河型,并论述了其特征及形成条件;通过41条现代水下分流河道的河型统计得出:顺直型水下分流河道是最常见河型,低弯度型、高弯度型、辫状型、网状型等河型少见且皆发育于不同地质背景的近岸水下环境。

Subaqueous distributary channel is one of the most important microfacies types and high-quality reservoirs in delta-front subfacies,but little research of subaqueous distributary channel pattern has been carried out.Whether there is meandering or braided pattern or any other subaqueous channels and whether there is high angle turning is not clear,which directly affect the research of fine characterization,architecture,three-dimensional heterogeneous model of subaqueous channel monosandbody in high water-cut stage and tertiary phase.Therefore,it is of great theoretic significance and badly needed to ravel the subaqueous channel pattern.Focused on this problem,our study used the remote sensing method（satellite image） which can integrally and finely reveal the plane configuration and the character of subaqueous channel to thoroughly dissect 41 present subaqueous channels and determine subaqueous channel patterns,to classify subaqueous channel region into 4 zones,3 types and 8 subtypes of channel pattern and discuss their characteristics and formation condition.Based on the statistics of the channel pattern of 41 present subaqueous channels,it is concluded that straight channel pattern is common,while low-sinuosity,high-sinuosity,braided and anastomosed channel patterns are rare and are normally developed in the nearshore subaqueous environment in different geological settings.