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贵州剑河八郎地区松山剖面的寒武系“清虚洞组”出露完整,总厚272 m,主要由灰岩、泥岩及白云岩组成.文中自下而上将“清虚洞组”分为4个岩性段:I段,灰色薄-中厚层含丰富生物碎屑泥质微晶灰岩;Ⅱ段,灰白色薄-中厚层含泥质微晶灰岩;Ⅲ段,灰色薄-中层含完整生物碎屑泥质微晶灰岩;Ⅳ段,灰色薄-中厚层含藻屑泥质微晶灰岩和细晶白云岩.Ⅲ段泥岩中产出包括软躯体化石在内的多门类化石,即剑河生物群.在前人工作的基础上,文中通过野外剖面观察、生物化石采集和微相分析等研究方法,对“清虚洞组”四个岩性段的沉积环境及其对应的海平面变化趋势进行了初步分析,认为“清虚洞组”沉积于含氧量较充沛、盐度正常、低能的较深水陆棚-陆棚边缘环境.中上部的特异埋藏化石群指示一个快速的沉积事件.分析结果表明,“清虚洞组”沉积期水体经历了3次变浅和2次变深的交替变化情况.其中,Ⅲ段沉积期,海底位于氧化还原界面附近;I、Ⅱ和Ⅳ段沉积期海底均位于氧化还原界面之上.“,”The Cambrian “ Tsinghsutung Formation ” crops out extensively in eastern Guizhou, it is perfectly exposed in the Songshan section at the Balang Village, Jianhe County. “Tsinghsutung Formation” is 272 m thick. Lithologically, the“ Tsinghsutung Formation ”, dominated by limestones, mudstones and dolomites can be subdivided into four members in ascending order: Thin-bedded to medium-bedded biodetritus pelmicrite (Member I); Thin-bedded to medium-bedded pelmicrite (Member Ⅱ); Thin-bedded to medium-bedded biodetritus pelmicrite (Member Ⅲ); Thin-bedded to medium-bedded pelmicrite with algae underlaying fine-crystal dolostones(Member IV). What's more, silt mudstone from the upper part of the “Tsinghsutung Formation” contains a Burgess shale-type Lagerstatte, known as the Jianhe biota. Based on detailed field investigation, microfacial analysis and palaeontological evidence, we proposed that the limestone-dominated “ Tsinghsutung Formation ” was deposited at the edge of deep shelf or deep shelf, which refers to a low water energy environment with high oxygen,normal salinity and good light conditions. Specifically, the Lagerstatte in the mid-upper part of the “ Tsinghsutung Formation ” indicates a rapid-burial event. In general, the sea level regarding the entire Tsinghsutung succession changes corresponding to three shallowing periods and two deepening periods, respectively. Our study also indicates that the Member Ⅲ may have been deposited nearby the redox surface,whereas the members I, Ⅱ and IV were probably deposited above the redox surface.