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济源市西南郊出露有中—上三叠统谭庄组,代表了济源中生代盆地充填的一部分。在湖相剖面中识别出六种岩相组成的两类相序,相序 1呈叠置的向上变粗的序列,由下到上由富有机质页岩 (相E,类型Ⅰ ),纹层粉砂岩 (相A)和水流波痕层理砂岩(相B)组成,记录了在温暖潮湿条件下常年性开放湖泊中小型河口坝三角洲的进积作用;相序 2缺少明显的垂直序列,由互层状细粒碳酸盐岩和粉砂岩(相C),变形层理和波浪改造砂岩 (相D),富有机质页岩(相E,类型Ⅱ)和粘土岩组成,虽然也代表了常年性开放浅水湖泊体系,但反映出很强的季节性气候控制特征。湖相剖面的相C中发育丰富的Skolithoslinearis组合,也反映出底层受季节性气候控制。文章深入探讨了该组上段浅湖沉积的环境演替及气候对沉积作用的控制作用,在湖泊演化过程中,很可能出现过几次水体分层。根据晚三叠世时期的古地理重建,推测谭庄组上段湖相沉积反映出的强烈季节性可以用潘加亚巨型季风影响的设想模式解释。
In the southwestern suburbs of Jiyuan City, there is a middle-upper Triassic Tanzhuang Formation that represents part of the filling of Jiyuan Mesozoic basins. In the lacustrine facies, two types of facies sequences of six facies facies are identified. The facies sequence 1 is superimposed upwards and thickens from bottom to top and consists of organic-rich shale (facies E, type I), lamina Siltstone (facies A) and flow-mark bedding sandstone (facies B), the hydrofacies of small and medium estuarine dams in perennial open lakes are recorded. Phase sequence 2 lacks apparent vertical sequence Interbedded fine-grained carbonate and siltstone (facies C), deformation stratification and wave-modified sandstone (facies D), organic-rich shales (facies E, type II) and clay rocks, although also representing perennial A shallow shallow lake system is open but reflects strong seasonal climate control features. The abundance of Skolithoslinearis assemblages in phase C of the lake facies also reflect the underlying seasonal climate control. The paper discusses in depth the environmental succession of the shallow lake deposits and the climate control effect on the sedimentation in the Upper Paleozoic. In the process of lake evolution, it is likely that there will be several times of water body stratification. According to palaeogeographic reconstruction in the Late Triassic period, it is speculated that the strong seasons reflected in the upper lacustrine sediments of the Tanzhuang Formation can be explained by the imagination mode of Panjanga monsoon influence.