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管状岩是古生代地层中最易识别的遗迹组构之一,它在地质历程中的盛衰受生物演化事件和环境变迁的共同控制,有研究表明管状岩在古生代呈现出逐渐减少的趋势.本文对云南巧家大包厂剖面下奥陶统红石崖组发育良好的Skolithos管状岩进行遗迹学和沉积学分析,发现其形成和保存主要受控于海水中营养物质、氧气含量等环境因素,而且与造迹生物的生存和竞争压力、内栖食泥生物的扰动程度以及水动力条件相对动荡、时有侵蚀或加积的背景条件密切相关.通过总结全球寒武纪-奥陶纪管状岩例证,发现这类遗迹组构整体上呈现出逐步衰退的趋势,即在早寒武世较为繁盛,中、晚寒武世相对匮乏,而奥陶纪最终走向衰亡,但这个过程并非是匀速的,中、晚寒武世陆缘浅海地区碎屑沉积的减少及高温气候、高海平面以及缺氧和贫营养环境在浅海区域广布的特点是造成管状岩发育低谷期的重要控制因素.
Tubular rocks are one of the most identifiable relics in the Paleozoic strata, and their ebb and flow in the geological history is controlled by both biological evolution events and environmental changes. Some studies show that the tubular rocks show a decreasing trend in the Paleozoic. The well-developed Skolithos tubular rocks of the Lower Ordovician Hongshiya Formation in the Qiaojia Daban Factory section of Yunnan Province were studied by means of trace and sedimentology. It was found that the formation and preservation of the Skolithos tubular rocks were mainly controlled by environmental factors such as nutrients and oxygen content in seawater, The existence and competition pressure of living creature, the degree of disturbance of habitat food mud creatures, and the relative turbulence of hydrodynamic conditions and the background conditions of erosion or accretion at any time.According to the example of the global Cambrian-Ordovician tubular rock, Such relict structures show a trend of gradual recession as a whole. That is to say, they are more prosperous during the Early Cambrian and relatively scarce in the middle and late Cambrian, while Ordovician finally declines, but the process is not uniform. The reduction of clastic sediments in the shallow sea area of the Late Cambrian continental margin and the characteristics of high temperature, high sea level and widespread anoxic and oligotrophic environment in the shallow sea area are caused by The important controlling factors of trough rock development.