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贵州省东北部江口县桃映震旦纪陡山沱组上部发现的庙河型生物群,包括宏体藻类、可能的后生动物、遗迹化石以及其它生物化石等,进一步证实这类宏体生物群在扬子地区震旦纪陡山沱晚期有较为广泛的分布。与鄂西庙河生物群、皖南蓝田植物群对比研究,震旦纪陡山沱晚期宏体生物群的生活环境主要为开阔浅海向台缘斜坡相过渡地带。通过对黔东北庙河型生物群的研究,认为陡山沱晚期的宏体生物群为以营固着生活方式为主,生活于透光性较好、具有一定水动力条件和一定含氧量的相对静水贫氧浅海环境;其固着基底为富含水份的未固结的粥性—软质基底。这些宏体生物群多呈半漂浮状竖立于海底,构成初步的“海底草原”,为生物群中依赖一定氧而生活、生长和繁殖的动物提供了必要的支持。生物死亡后,大部分生物躯体倒伏于沉积物表面,在贫氧和较快沉积速率的沉积环境中,生物遗体被较好保存,并很快被沉积物所埋藏。随着沉积物的增厚,生物遗体被完全封闭,导致生物遗体腐烂和分解过程终止,使其得以很好保存。较快的沉积速率、贫氧和相对平静水体的环境是生物群得以很好保存的重要因素。
The Miaohe-type biota, including macroalgae, probable metazoan, trace fossils and other biological fossils found in the upper part of the Sinian Doushantuo Formation in Taoying, Jiangkou County, northeastern Guizhou Province, further confirmed that this type of macro-organism In the late Sinian Doushantuo period, there is a more extensive distribution. Compared with the Miaohe biota in the western Hubei Province and the Lantian flora in southern Anhui, the living environment of the macroscopic biome in the late Sinian Doushantuo is mainly the transitional zone from shallow sea to platform slope. Based on the study of the Miaohe-type biota in northeastern Guizhou Province, it is concluded that the macroscopic biota in the late Doushantuo phase mainly dominated by camp-based lifestyles, living in better translucency, with certain hydrodynamic conditions and certain oxygen content Relatively static water oxygen-poor shallow sea environment; its fixation substrate is water-rich uncoiled porridge - soft substrate. These macroscopic biomes, mostly semi-floating on the seabed, constitute the initial “seagrass grassland” and provide the necessary support for animals living, growing and reproducing in certain biota. After biological death, most of the biological body lodging on the sediment surface, in the deposition environment of oxygen-poor and faster deposition rate, the biological remains are well preserved and quickly buried by sediments. As the sediment thickens, the biological body is completely closed, causing the decay and decomposition of the biological body to stop, allowing it to be well preserved. Faster sedimentation rates, oxygen-depleted and relatively calm water environments are important factors in the well-preserved biota.