辽河断陷西部凹陷白垩纪火山岩特征

Characteristics of Cretaceous volcanics in the western depression of Liaohe fault depression

通过全区综合录井资料的统计、大量的岩心观察,并利用薄片鉴定、阴极发光、扫描电镜、X衍射分析、图像分析、岩石化学分析、同位素年龄测定、包裹体温度测定等10余种方法,对辽河断陷西部凹陷白垩纪火山岩分布、岩石类型、岩石系列、形成的构造背景及储层特征进行了研究。结果认为,白垩纪火山岩以中酸性火山熔岩和火山碎屑岩为主,局部发育基性熔岩;中酸性火山岩以钙碱性系列为主,形成于挤压造山环境,储集性能较好,而白垩纪基性熔岩以碱性系列为主,形成于裂谷环境,储集性能较差。火山岩相关特征的明确对于本区的勘探开发具有重要的指导意义。

This paper studies Cretaceous volcanics distribution, rock types, tectonic setting and reservoir characteristics in the western depression of Liaohe fault depression through statistics of compound logging data, core observation, thin section identification, cathodeluminescence, scanning electron microscope, X-ray diffraction analysis, image analysis, rock chemical analysis, isotope age testing, and inclusions temperature testing. The study shows that Cretaceous volcanics mainly consist of medium acidic volcanic lava and volcanoclastic rocks, with locally developed basic lava; medium acidic volcanics mainly consists of calc-alkalic series, was formed in compressive orogenic environment, and has good reservoir property, while Cretaceous basis lava mainly consists of alkalic series, was formed in rift environment, and has poor reservoir property. Understanding of volcanic rock characteristics is of guiding importance to the exploration and development in this area.