塔里木盆地白垩系层序地层学

Sequence of cetaceous in Tarim Basin

通过地震剖面、测、钻井、野外地质露头以及岩心等资料的综合分析,白垩系可识别出8个三级层序边界,这些层序边界均为Ⅰ型层序边界。根据8个层序边界白垩系可划分出7个三级层序,分别为KSQ1~KSQ7层序。这些层序均可识别出低位体系域、湖侵体系域,由于基准面下降期间地层的剥蚀作用使高位体系域多发育不全。顺托果勒和阿瓦提地区大部分剖面缺失KSQ6和KSQ7层序。在研究区南部、东部和北部等盆地边缘区域白垩系下部地层呈现明显的下超和上超,导致缺失KSQ1或KSQ2层序。在盆地内部各层序均有分布。白垩系层序的发育特征明显受到构造运动、气候、沉积期古地貌和湖盆性质的影响。

Based on comprehensive analysis of seismic data, drilling data, logging data and outcrop data, 8 sequence boundaries can be recognized, and all of the boundaries belong to type I. According to 8 sequence boundaries, 7 third-order sequences can be divided in Cretaceous： these are sequences KSQ1-KSQ7. Every sequence can be subdivided into lowstand system tract and transgressive system tract. Highstand system tracts remain few because of eroding during datum level falling. Sequences KSQ6 and KSQ7 are absent in Shuntuoguole and Awati area. Lower part of sequences downlaps on basin margin in southern, eastern and northern parts of the basin, which results in absence of sequences KSQ1 and KSQ2. All of sequences are present inner basin. Sequences in Cretaceous are controlled by tectonic activity, climate, palaeogeomorphology and basin features.