吐鲁番坳陷中下侏罗统层序地层格架内有利储集砂体分布规律

利用层序地层学理论,在吐鲁番坳陷中下侏罗统确定3类层序界面识别标志,划分出5个三级层序,10个四级层序,建立吐鲁番坳陷中下侏罗统的层序地层格架.研究结果表明:吐鲁番坳陷侏罗纪时期南部物源发育,中下侏罗统地层具有南薄北厚的特点;其层序形成具缓坡背景浅水湖盆和具沉积坡折背景浅水湖盆2种发育模式;吐鲁番坳陷中下侏罗统共发育5套主要的有利储集砂体,其中三间房组下部沉积的辫状河-曲流河三角洲中厚层-厚层砂岩层是研究区最有利储集砂体.

Development of reservoir sandbody in sequence stratigraphic framework of middle-lower Jurassic in Turpan Sag

Based on sequence stratigraphy theory, three types of identification signs of sequence interface were identified and middle-lower Jurassic was divided into five third-order sequences and ten fourth-order sequences, then the sequence stratigraphic framework was established in Turpan sag. The results show that the main source of Jurassic in southern region is plentiful, and the stratum is thick in north and thin in south and there are two developmental models of shallow lake basin with gentle slope background and deposit slope break background in Turpan sag. There develops five sets of major favorable reservoir sandbody of middle-lower Jurassic in Turpan sag, and the middle thick-thick sandstone layer of braided river-meandering river delta in lower part of Sanjianfang set deposition is the most favorable reservoir sandbody in the study area.