1.Research Institute of Planning and Exploration, Shandong Bureau of Coal Geology, Jinan , China;2.Academician Workstation of Research Institute of Planning and Exploration, Shandong Bureau of Coal Geology, Jinan , China;3.Shale Gas(oil) and Coalbed Methane Technology Center of Shandong Bureau of Coal Geology, Jinan , China

为了探究海陆过渡相含煤岩系层序地层特征,基于垂向沉积序列、岩性组合、测井响应、地球化学特征,运用高分辨率层序地层理论和方法,对贵州盘县矿区上二叠统进行了层序地层研究。研究结果表明:以构造不整合面、区域海退面、沉积间断面、侵蚀不整合面、淹没不整合面等三级层序界面,将研究区上二叠统划分为4个三级层序。层序结构为典型的二元体系域,由海侵体系域(TST)和高水位体系域(HST)组成,低水位体系域(LST)不发育,呈现慢速海侵、快速海退的特点。研究区厚煤层主要分布于海侵体系域早中期,此时基底沉降缓慢,可容空间增加速率与泥炭堆积速率基本保持平衡。

In order to explore the the sequence stratigraphy characteristics of coal bearing formation with marine-continental transitional facies, the high resolution sequence stratigraphy theory and method were applied to the study on the Upper Permian in Panxian county, western Guizhou, by a number of features such as the biostratigraphy and chronostratigraphy data, well vertical sedimentary sequences, well log response and geochemical characteristics. The study showed that based on five third-order sequence boundary, such as the regional tectonic unconformity surface, regional regression unconformity surface, exposure unconformity surface, regional transgression unconformity surface and drowning unconformity surface, Upper Permian in study region was divided into four third-order sequences. The sequence structure was the typical dual characteristic. Transgressive system tract (TST) and highstand system tract (HST) were the main part in sequence structure, and lowstand system tract (LST) was not well-developed. It presented the characteristics of slow transgression and rapid regression. The thick seams in the study region mainly distributed in the the early and middle TST. At the moment, the foundation subsidence was gently slow, the accommodation space increased rate and the peat accumulation rate was basically kept in the balances.