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硅质碎屑物质对分泌碳酸盐的生物的抑制作用,使人们得出了这样的概念,即:很少会形成由碳酸盐和硅质碎屑物质的混合物组成的沉积物。但是,在许多现代和古代陆架沉积中却包含着一系列由“混合”成分组成的沉积物。引起这种混合的作用可分为四类:(1)间断混合,即突发的风暴和其它周期性极强的事件把沉积物从一个沉积环境搬运到另一个环境;(2)相混合,即沉积物沿着不同相之间的边界发生混合;(3)原地混合,即碳酸盐是由堆积在硅质碎屑底层之上或之内的原地或准原地死亡钙质生物组成的;(4)源地混合,即混合物是由于附近碳酸盐源区的隆升和冲蚀而形成的。混合沉积物的异化成分均为珊瑚藻和有孔虫—软体动物。有孔虫—软休动物组合最为常见,这是由于浊度的升高,不稳定底层的作用,以及与硅质碎屑的注入有关的过滤-摄食机制的阻塞而造成的。
The inhibitory effect of siliceous clastic material on the bio-secreting carbonate gives rise to the notion that deposits consisting of a mixture of carbonate and siliceous clastic material are seldom formed. However, many modern and ancient shelf sediments contain a series of sediments composed of “mixed” components. The effects of this mixing can be divided into four categories: (1) intermittent mixing, ie sudden storms and other highly cyclical events that carry sediment from one sedimentary environment to another; (2) That is, the sediment is mixed along the boundary between different phases; (3) In-situ mixing, ie, the carbonate is formed by the in situ or quasi-dead calcareous organisms deposited on or in the bottom of the siliceous debris (4) source mixing, ie, the mixture is formed by uplift and erosion of nearby carbonate source areas. The alienation components of the mixed sediments are coral algae and foraminifera molluscs. The combination of foraminifera and mollusc is the most common, due to increased turbidity, the effect of unstable substrates, and obstruction of the filter-feeding mechanism associated with the injection of siliceous debris.