陆相湖盆砂砾岩体层序地层学研究——以济阳坳陷罗家—垦西地区为例

Study on sequence stratigraphy of glutenite in terrestrial lacustrine basin-taking Luojia & Kenxi area of Jiyang Depression as an example

陆相湖盆及其沉积体的特殊性决定了陆相湖盆层序地层学研究的特点、发展方向及方法。单一厚层的砂砾岩体的层序地层学研究应从相邻沉积体及砂砾岩体的沉积特征入手,研究湖盆转型所反映的砂砾岩沉积体系的转型,确定沉积层序类型及期次,利用钻井、测井和地震资料识别层序界面并划分层序;在层序内部识别最大湖泛面或与之相当的沉积转换面,划分体系域;采用比较有效的手段划分准层序,在层序内部以湖泛面(沉积转换面)为关键面,分别向上、向下对准层序建立高精度等时地层格架。该方法在济阳坳陷罗家—垦西地区取得了较好的效果。

The particularity of terrestrial lacustrine basins :and their deposi-tional systems decided the characteristics, development trend and methods of the lacustrine basin sequence stratigraphy study. Sequence stratigraphy study of single thick - layer glutenite should proceed with depositional characteristic of neighbouring deposi-tional system and glutenite, investigate transition of the glutenite depositional system reflected by transition of the lacustrine basin, determine depositional sequence type, period and order. U-sing drilling,well -logging and seismic data identified sequence interface and divided sequence. The biggest lake flood surface or comparative depositional conversion surface was confirmed and system domain was classified inside the sequence. Subsequence was classified by more effective means, high accuracy isochronous stratigraphic frame was set up upward and downward taking lake flood surface as the key surface. Preferable effect was a-chieved by using this method in Luojia&Kenxi area of Jiyang Depression.