鄂尔多斯盆地姬塬地区长6段沉积相特征和砂体展布

姬塬地区位于鄂尔多斯盆地中西部，通过岩心观察和测井资料分析，认为晚三叠世长6时期该区北、西两侧都发育有河控型三角洲-浅湖沉积体系。基于高分辨率层序地层学分析的岩相古地理编图结果非常清晰地显示了研究区长6段砂体展布特征，同时通过古盐度恢复，首次确定了该区湖岸线的位置，从而确定研究区主要发育三角洲前缘亚相，三角洲平原只在东北一隅有小范围分布。耿-史地区长6段不同沉积时期岩相古地理面貌，特别是古岸线的确定，对于指导该区长6油藏下一步的开发具有极其重要的意义。

Sedimentary facies characteristics and sandbody distribution of Chang 6 member in Jiyuan area of Ordos Basin

Based on the core observation and logging analysis, it is believed that fluvial-dominated delta and shallow lacustrine sedimentary system developed well during Chang 6 period in Late Triassic in the north and west of Jiyuan area which is located in the Midwest of Ordos Basin. The lithofacies and paleogeography mapping based on high resolution sequence analysis show the sandbody distribution clearly. The paleoshoreline in this area is defined by paleosalinity recovery. Deltaic front subfacies mainly developed in the study area, with small-scale of deltaic plain in northeast. The reconstruction of lithofacies and paleogeography, especially the definition of paleoshoreline of Chang 6 member in Gengwan-Shijiawan area is significant for the further exploitation in this area.