鄂西南五峰——龙马溪组富笔石细碎屑岩非常规沉积作用  

Unconventional Sedimentation of Graptolite-rich Fine-grained Clastic cks of Wufeng-LongmaxiFormationin Southwestern Hubei RoProvince,China

作　　者：贺萍 王青春 谷海艳 申方乐 HE Ping;WANG Qing-chun;GU Hai-yan;SHEN Fang-le(Hebei GEO University,Shijiazhuang 050031,China;Baoding University of Technology,Baoding 071000,China;Huaxin College of Hebei GEO University,Xinle 050799,China)

机构地区：[1]河北地质大学地球科学学院,河北石家庄050031 [2]河北地质大学保定理工学院,河北保定071000 [3]河北地质大学华信学院,河北新乐050799

出　　处：《河北地质大学学报》2022年第2期56-61,共6页Journal of Hebei Geo University

基　　金：国家自然科学基金项目(41802016);山东省沉积成矿作用与沉积矿产重点实验室开放基金项目(DMSM20190027);国家级、省级一流本科课程“沉积岩岩石学”建设项目;河北省、河北地质大学教改项目(2020GJJG589、2020J03);河北省研究生示范课程建设项目(KCJSX2021092)。

摘　　要：有关细碎屑岩沉积作用的研究相对较为薄弱,论文选取鄂西南五峰—龙马溪组富笔石细碎屑岩为研究对象,探讨岩石定名中的分歧及其沉积环境。研究区细碎屑岩中,粉砂级石英颗粒含量较高、磨圆较差,发育微平行层理和微粒序层理,而且较完整的笔石生物化石大多富集于黏土级沉积物中,正常陆棚沉积难以圆满解释其成因,论文引入事件性水下重力流沉积,并建立了理想沉积模式,能够较好地解释细碎屑岩中特殊的沉积现象。据此推断,海相细碎屑岩应该是泥质重力流、异重流、浊流等水下流体与正常陆棚沉积共同作用的产物,二者有效组合,对于非常规油气资源具有重要意义。The sedimentation research of fine-grained clastic rocks is relatively weak. This paper selects graptolite-rich fine-grained clastic rocks of Wufeng-Longmaxi Formation in southwestern Hubei Province as the research object to discuss the differences in rock naming and sedimentary environment. The sedimentary characteristics of fine-grained clastic rocks in the study area such as the higher content and poor roundness of silty quartz particles, the micro-parallel beddings and micro-graded beddings, and the enrichment layers of complete graptolites in clay sediments are not the prominent characteristics in normal continental shelf deposition environment. The paper introduced event sedimentation of underwater gravity current deposits and established the ideal sedimentary model. It can well explain the special sedimentary phenomena in fine-grained clastic rocks. It can be inferred that the marine fine-grained clastic rocks are the products of the interaction of underwater gravity current deposits such as argillaceous gravity flow, density current, turbidity current with normal continental shelf deposits. The effective combination of normal continental shelf deposits and the event underwater gravity flow deposits is of great significance for the unconventional hydrocarbon resources.

关 键 词：笔石 细碎屑岩 陆棚 水下重力流 

分 类 号：P618.13[天文地球—矿床学]