MARKER BEDS FOR STRATIGRAPHIC DIVISION AND CORRELATION IN LIAOHE FAULT BASIN

The Paleogene system is characterized by violent segmentation, greatly various thickness and lithology vertically and horizontally as a result of the complex geological structure of Liaohe fault basin. Finding and identifying marker beds for fine stratigraphic division and correlation have always been the difficulty in stratigraphic research in the area, thus restricting the deployment of oil-gas exploration and development. Based on the analysis of tectonic sedimentary evolution of the basin, the paper systematically studies nearly 1 000 exploratory wells in the Western Sag through multiple stratigraphic division and correlation, identifying 7 regional marker beds of Paleogene, describing the contact relations and lithologic-electric characteristics for 14 types of bottom boundaries of Paleogene Shahejie Formation, and dividing different distribution areas by bottom boundary types within one stratigraphic unit on the basis of representative wells, which makes the stratigraphic division and correlation of continental fault basins more simple, detailed and easy to operate, and provides basic support for fine oil and gas exploration.