沧东-南皮凹陷孔店期古盐度与古环境演化  

Analysis of paleosalinity and paleoenvironmental evolution of Kongdian Stage in Cangdong-Nanpi Sag

作　　者：秦敏 Qin Min(Exploration and Development Test Center,Exploration and Development Research Institute of Liaohe Oilfield,Panjin 124010,Liaoning,China)

机构地区：[1]辽河油田勘探开发研究院勘探开发试验中心,辽宁盘锦124010

出　　处：《地质学刊》2023年第2期129-134,共6页Journal of Geology

基　　金：国家自然科学基金项目(40972083)资助。

摘　　要：内陆封闭湖泊的盐度与湖平面具有同步反向变化的特点,通过古盐度研究可推测沉积时期的古气候状况。通过Sr/Ba、Th/U含量比值及C、O同位素的含量变化分析,对沧东—南皮凹陷孔店期各层序古盐度的变化进行系统研究,结合孢粉及岩性组合,推断该区孔店期的水体性质及各层序间古环境的演化。综合认为孔店期整体水体性质为半咸—微咸水,水体深度呈浅→深→浅的变化规律,古气候变化特征为半干旱→湿润→半干旱→干旱气候。The salinity of inland closed lakes changes synchronously and inversely with the lake level.The paleoclimate of sedimentary period can be inferred by the study of paleosalinity.Based on the analysis of the content ratios of Sr/Ba,Th/U and the changes of carbon and oxygen isotopes,this paper systematically studies the paleosalinity changes of the Kongdian Stage in the Cangdong-Nanpi Sag,and infers the water properties and palaeoenvironmental evolution of each sequence in the Kongdian Stage based on the palynological and lithological assemblages.It is concluded that the overall water quality of the Kongdian Stage was brackish to light brackish water,and the water depth changed from shallow to deep and then to shallow,and the paleoclimate changed from semiarid to humid and then to semiarid and arid.

关 键 词：古盐度 古气候 湖平面变化 沉积环境演化 孔店组 沧东-南皮凹陷 

分 类 号：P532[天文地球—古生物学与地层学]