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奥陶纪末赫南特冰期和生物大灭绝事件结束后,扬子陆表海区志留纪兰多维列世早期的海进序列伴随着生物逐渐复苏的过程。在黔中古陆北缘石阡一带鲁丹晚期至晚埃隆早期的香树园组属近岸浅水带灰岩—碎屑岩沉积区。石阡县城北香树园剖面的香树园组以灰岩为主,夹含少量粉砂质、泥质陆源碎屑岩,频繁出现含丰富壳相后生动物化石碎片形成的薄层滩相单元。与大颗粒壳相化石为主形成的各类生物层状礁类似,生屑滩多为动荡流水改造的后生动物碎片近源沉积。滩相具有较高的生物多样性和化石丰度,是奥陶纪末生物礁复苏前浅海暖水区广泛分布的生态单元。此地香树园组缺少粗砂级以上的陆源碎屑颗粒,也无岩屑颗粒,指示沉积物具有较高的成熟度。推测黔中古陆靠近石阡的部位已经夷平,黔东北浅海区在香树园组灰岩沉积期具有偏低的海水浑浊度和碎屑岩沉积速率,生屑滩相灰岩单元是在正常盐度和高清洁度的环境下堆积的,附近有粉砂-泥级颗粒注入,但无大型河流输入丰富的淡水和陆源粗碎屑。
After the end of Ordovician Hernnén ice age and mass extinction, the early marine sequence of the Silurian orchidovsky in the Yangtze Terraina was accompanied by a gradual resuscitation. In the Qianqian area of the northern edge of the ancient Central Guizhou Province, the early Linden-late Erhualan Hashimu Formation in the northwestern margin of Central Guizhou is a limestone-clastic sedimentary area near the shallow water belt. The Xiangshuyuan Formation of the Xiangshuanyuan section in the north of the Shiqian County is dominated by limestone and contains a small amount of silty and muddy terrigenous clastic rocks. Thin-layer beach facies units formed by fossilized animal fragments rich in crusts frequently occur . Similar to the large-scale crust-phase fossils, all kinds of bio-layered reefs are similar. The swarms are mostly near-source sediments of metazoa fragments modified by turbulent water flow. The beach facies have high biodiversity and fossil abundance, and are widely distributed ecological units in shallow-sea warm water areas before the end of Ordovician reef reef. The lack of gypsum-derived terrigenous clastic particles and detritus particles above the Xiangshuyuan Formation indicate that the sediments have a high degree of maturity. It is speculated that the parts of ancient Chinese land near Shiqian have been leveled off. The shallow sea areas in northeast Guizhou have low turbidity and detritus deposition rate of seawater in Xiangshuyuan limestone sedimentary period. Salinity and high cleanliness of the environment, there is near the silt - mud-level particles injected, but no large rivers into the rich freshwater and terrestrial coarse debris.