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对华北中、新元古代燕山盆地发育的三个主要阶段的生物群面貌进行了总结,三个阶段分别为:长城系下部碎屑岩沉积阶段(A),长城系上部至蓟县系碳酸盐岩沉积阶段(B),蓟县系上部至青白口系碎屑岩沉积阶段(C).其中阶段B是本研究的重点研究层位.B阶段的页岩相化石虽然不甚丰富,但燧石相生物化石却有着较高的分异度和丰度,并具有多种类型的形态及纹饰.此外B阶段中缺乏大直径个体.阶段B的生物群丰度、分异度、浮游生物和底栖生物分异度比例、底栖球状化石平均直径、球形化石最大直径在时间尺度上具有明显的变化规律.笔者从中识别出了两个典型的生物群演变事件,两个事件都和地质事件相耦合.事件一发生于大红峪组三段,这一时期生物群中大个体浮游生物化石十分繁盛,推测可能与火山活动有关.事件二发生于高于庄组三段,这一时期的生物群发生了整体面貌的更替,该更替事件与叠层石衰减、海洋元素地球化学指标以及碳同位素等多个因素的变化耦合.
The three major stages of the development of the mid-Neoproterozoic Yanshan Basin in North China are summarized as follows: the sedimentary stage of clastic rocks in the lower part of the Great Wall System (A), the upper part of the Great Wall to the Jixian carbonate Rock depositional stage (B), upper Jixian to Qinglaikou clastic sedimentary stage (C), of which stage B is the key study horizon in this study. Although the shale facies in stage B are not abundant, the chert phase Biofuels have a higher degree of diversity and abundance, and have many types of morphology and ornamentation, and lack of large-diameter individuals in stage B. The abundance, diversity, plankton and benthos Biological diversity, the average diameter of benthic spherical fossils, and the maximum diameter of spherical fossils in the time scale of the obvious changes in the author identified two typical biota evolution events, both events are coupled with the geological events The first event occurred in the third section of Dahongyu Formation, during which the large individual zooplankton fossils in the biota are very prosperous, suggesting that it may be related to volcanic activity.The second event occurred in the third section of the Gaozhuangzhuang Formation and the biota occurred during this period Whole Face of the replacement, the replacement event stromatolites attenuation, the plurality of coupling factors marine elements change indicators and carbon isotope geochemistry.