层序地层学在齐家北地区的应用

以层序地层学的原理为指导，从地震层序、测井曲线、沉积层序分析入手，对泉头组三段至青山口组二、三段层序地层格架进行了研究，划分出3个三级层序，并划分出了体系域，确立了地层格架。其中，层序Ⅰ相当于泉头组三段至青山口组二、三段下部地层，发育低水位体系域、水进体系域和高水位体系域，是一个完整的旋回；层序Ⅱ代表的是青山口组二、三段中部沉积，低水位体系域不发育，只发育水进体系域和高水位体系域；层序Ⅲ代表青山口组二、三段中上部地层，与层序Ⅱ有相似特征。

Application of sequence stratigraphy in North Qijia area

Based on theory of sequence stritigraphy, this paper analyzes seismic sequence, logging curves and sedimentary sequence, studies formation framework from Member 3 in Quantou Formation to Member 2 and 3 in Qingshankou Formation. It divides them into three 3-level sequences, divides reef limestone, and determines formation framework. Sequence I corresponds to formation from Member 3 in Quantou Formation to lower part of Member 2 and 3 in Qingshankou Formation, developing low water level reef limestone, water transgression system domain and high water level system domain, being a complete cycle. Sequence II corresponds to middle part of Member 2 and 3 in Qingshangkou Formation, only developing water transgression system domain and high water level system domain and without low water level system domain. Sequence III corresponds to upper part of Member 2 and 3 in Qingshankou Formation, with similar characteristics with Sequence II.