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黔中织金地区以黑色页岩为特征的下寒武统牛蹄塘组中部发育有一套厚约9.2m的白云岩,且在白云岩中由下至上发育有较强水动力成因的小型冲刷构造、小型槽状交错层理以及水动力相对较弱的低角度交错层理和水平层理,表明黔中地区早寒武世牛蹄塘组沉积期曾经出现过短暂的、碳酸盐浅滩相的沉积环境,同时也揭示了早寒武世牛蹄塘组沉积期并非一直处于滞留、低能的还原环境。另外,牛蹄塘组底部黑色页岩之下的紫红色泥岩以及明心寺组底部的粉砂岩整合于牛蹄塘组顶部的黑色页岩,表明牛蹄塘组沉积早期和晚期水体也相对较浅。因此,黔中织金地区牛蹄塘组中白云岩的发现,表明了在牛蹄塘组沉积期至少存在二次以上的三级海平面升降变化,为研究全球海平面的变化提供了新的材料。
In the Zhijin area of central Guizhou, a set of dolomite with a thickness of 9.2 m is developed in the middle of the Lower Cambrian Niutitang Formation, characterized by black shale. In the dolomite, small scour with strong hydrodynamic causes is developed from the bottom up The structure, the small trough cross-bedding and the relatively weak hydrodynamic low-angle cross-bedding and horizontal bedding show that there was a transient deposition of carbonate shoal facies during the deposition of the Niutizang Formation in Central Guizhou during the deposition period Environment, but also revealed that the Precambrian Niutitang Formation has not been in a detention and low-energy environment for a long time. In addition, mauve mudstone under the black shale at the bottom of the Niutitang Formation and siltstone at the bottom of the Mingxinsi Formation are integrated with black shale at the top of the Niutitang Formation, indicating that the sediments of the Niutitang Formation are also relatively early and late shallow. Therefore, the discovery of dolomite in the Niutitang Formation in the Zhijin area of Central Guizhou shows that there are at least two third-order sea-level changes in the Niutitang Formation during the depositional period, which provides a new method for studying the global sea level changes material.