塔里木盆地柯坪地区奥陶系高丰度海相烃源岩成因探讨  

Genesis of Ordovician Marine Source Rocks of High Organic Abundance in Keping Region,Tarim Basin

作　　者：廖晓[1,2] 王震亮[1,2] 余朱宇 于常青[3] Liao Xiao;Wang Zhenliang;Yu Zhuyu;Yu Changqing(a. State Key Laboratory of Continental Dynamics;1b. Department of Geology, Northwest University, Xi＇an 710069,Chin;2. Institute of Geology,Chinese Academy of Geological Sciences, Beijing 100037, China)

机构地区：[1]西北大学大陆动力学国家重点实验室,西安710069 [2]西北大学地质学系,西安710069 [3]中国地质科学院地质研究所,北京100037

出　　处：《地质科技情报》2018年第2期59-64,共6页Geological Science and Technology Information

基　　金：国家自然科学基金项目(41672121);中国地质调查局项目(12120114009701)

摘　　要：柯坪地区中-上奥陶统萨尔干组与上奥陶统印干组海相烃源岩是塔里木盆地重要的烃源岩组成部分,对其特征及其成因机制的研究具有重要的科学意义和经济价值。在通过岩石热解分析对比研究萨尔干组与印干组海相烃源岩现今地球化学特征的基础上,通过微量和稀土元素从地球生物学的角度对其特征差异性成因机制进行了探讨。结果表明,萨尔干组和印干组黑色页岩现今均处于成熟-高成熟阶段,萨尔干组的有机质丰度和古生产力水平都比印干组高,而古氧相和埋藏效率均较差。与印干组相比,Caradoc早期大洋缺氧事件使得柯坪地区同时期沉积的萨尔干组页岩古生产力水平得到了显著提高,在埋藏效率低、氧化还原条件差的情况下仍为高有机质丰度烃源岩。The marine source rocks of Middle-Upper Ordovician Saergan Formation and Upper Ordovician Yingan Formation are very important hydrocarbon source rocks of Tarim Basin. The study of their charac- teristics and genesis is of great scientific and economic significance. This paper studies the geochemical characteristics of Saergan Formation and Yingan The genetic analysis was conducted to contrast Formation marine source rocks by rock pyrolysis analysis. the different characteristics of Saergan shale and Yingan shale on the basis of trace elements and rare earth elements. The result shows that both Saergan shale and Yingan shale are in the mature-high maturity stage. Both the organic matter abundance and the level of pa- leoproductivity of Saergan Formation are higher than those of Yingan Formation. However, the condition of paleo oxygenation facies and burial efficiency are worse. Compared with Yingan shale, the paleoproduc- tivity of Saergan shale isobviously enhanced by the early Caradoc oceanic anoxic event in Keping region. Moreover, Saergan shale still contains high organic matter abundance source rock in the conditions of low burial efficiency and poor redox.

关 键 词：大洋缺氧事件 古生产力 印干组 萨尔干组 海相烃源岩 柯坪地区 

分 类 号：P618.3[天文地球—矿床学]