The depositional sequences of braided rivers mainly consist of braided channel lag deposits and mid - channel bar sandstones 辮狀河沈積主要發(fā)育河道和心灘微相,泛濫平原微相不太發(fā)育。
The depositional sequences of meandering river are typical of the development of point bars , crevasse - splays , natural levees and flood plains 曲流河沈積以發(fā)育點(diǎn)砂? 、決口扇、天然堤和泛濫平原等微相單元?特徵。
According to the abundance well logging , mud logging and core analysis data , gaotaizi reservoir has been classified into four sand group with the principle of cycle comparison and classified control . based on the detailed study of lithologic character , sedimentary structure , paleontologic fossils , depositional sequence , rock association and logging data , the microfacies of the studied area are divided into such seven types : subaqueous distributary channel microfacies ; river mouth bar microfacies ; subaqueous interdistributary channel microfacies ; subaqueous crevasse channel microfacies ; subaqueous natural barrier microfacies ; distal bar microfacies ; delta front sheet sand microfacies . the characteristic of each sedimentary microfacies are described detailedly 通過(guò)研究大量測(cè)井、錄井資料和巖芯資料,依據(jù)“旋回對(duì)比,分級(jí)控制”的原則,把研究區(qū)高臺(tái)子油層劃分為g 、 g 、 g 、 g四個(gè)砂層組。通過(guò)對(duì)研究區(qū)巖性、沉積構(gòu)造、古生物、沉積序列、巖石組合及測(cè)井曲線特征進(jìn)行研究的基礎(chǔ)上,認(rèn)為研究區(qū)高臺(tái)子油層屬于三角洲前緣亞相沉積,并將研究區(qū)沉積微相劃分為:水下分流河道、河口壩、水下分流河道間、水下決口扇、水下天然堤、遠(yuǎn)砂壩、席狀砂等七種微相類(lèi)型。