塔中地区西部倾没端奥陶系高频层序地层格架中岩溶发育特征

研究区位于塔中隆起的西部倾没端。奥陶系属碳酸盐岩台地相缝洞型储层。深入解剖其岩溶发育特征,探讨岩溶发育规律,将对该区的储层预测具有重要意义。借助FMI成像测井资料对该区溶蚀孔洞发育情况进行了精细的解剖,有效的确定了溶蚀孔洞的发育形态、大小、疏密程度及其纵向发育规律。明确了该区溶蚀孔洞主要发育在下奥陶统鹰山组中。以高分辨率层序地层理论为指导,结合碳酸盐岩沉积特征,提出以水退面作为高频层序划分的界面,建立高频层序地层格架,并探讨了层序与岩溶发育的关系,揭示出高频层序界面对岩溶发育的控制作用。旨在探索预测碳酸盐储层的新思路。

The Karst Development Feature in Sequence Stratigraphic Framework of the Western Pitching End of Tazhong Area

The research area is located in the western pitching end of Tazhong uplift.Ordovician reservoir is fractured-caven reservoir of carbonate platform.To clarify the developed feature and rule of karst is the key for settling the exploration problem in the area.Using of FMI logging data,the paper accurately anatomizes the characteristics of a dissolved cave,and effectively makes sure the shape,size,density and longitudinal developed rule of a dissolved cave.The research reveals that the dissolved cave in the area is mainly developed in the Yingshan Formation of low Ordovician.Guiding by high resolution sequence stratigraphy and in combination with the sedimentary feature of carbonate rock,the author puts forward that dereliction surface isused as high frequency sequence interface to establish the sequence framework,discusse the relation between sequence and karst development,and reveal the controlled function of high frequency sequence surface to karst development and probe into a new clew of carbonate reservoir prediction.