气候变化领域集成服务门户(CCPortal): Unusual shallow marine matground-adapted benthic biofacies from the Lower Triassic of the northern Paleotethys: Implications for biotic recovery following the end-Permian mass extinction

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DOI	10.1016/j.earscirev.2018.07.012
	Unusual shallow marine matground-adapted benthic biofacies from the Lower Triassic of the northern Paleotethys: Implications for biotic recovery following the end-Permian mass extinction
	Feng X.; Chen Z.-Q.; Bottjer D.J.; Wu S.; Zhao L.; Xu Y.; Shi G.R.; Huang Y.; Fang Y.; Tu C.
发表日期	2019
ISSN	0012-9063
起始页码	194
结束页码	219
卷号	189
英文摘要	We report two shallow marine, ichnofauna-bivalve-microbial mat biofacies from the Lower Triassic Xiahuancang Formation of the southern Qilian area, Qinghai Province, northwestern China, which was located at moderate-high paleolatitudes on the northern margin of the Paleotethys Ocean. Paleoenvironmental analyses show that Members I and II of the Xiahuancang Formation represent a shoreface and a lower shoreface to offshore transition setting, respectively. Biofacies 1, recognized from Member I, is characterized by a diverse ichnofauna (including deep-tiers of Rosselia and Diplocraterion), Claraia-dominated bivalves, and microbially induced sedimentary structures (MISSs). Biofacies 2, in succeeding Member II, is dominated by a diverse ichnofauna, epifaunal and shallow infaunal bivalves, and wrinkle structures. Primary co-occurrences, preservational features, and palimpsest or crosscutting relationships of all components within the biofacies indicate that microbial mats, bivalves, and trace-makers actively interacted with one another during deposition. They largely represent contemporaneous biotic associations. Microbial mats are interpreted to have grown under well-oxygenated conditions after storm deposition due to the association of deep-tiering infauna and diverse epifauna as well as well-developed cross-stratification, and the top layer of microbial mats could serve as an oasis for metazoans. Microbial mats not only proliferated in harsh environments, but also coexist with epifauna and deep-tiering infauna in well-oxygenated settings following the end-Permian crisis. Their occurrences in the Early Triassic are unrelated to environmental stresses, which are coincident with their sedimentologic record from other geological time intervals. Apparently, the southern Qilian ichnofauna-bivalve-microbial mat biofacies with juxtaposed epifauna, infauna and MISS- or wrinkle-related microbial mats represents a matground-adapted benthic metazoan ecosystem in the earliest Triassic, which provided sufficient oxygen, food, and other hydrodynamic conditions hospitable for metazoans and ecosystems to recover and reached a fairly high level (recovery stage 3) in a tough time when most biotas suffered biotic depletion and environmental stress. The biotic components in unique biofacies may represent a phase shift community in siliciclastic settings during the Early Triassic. © 2018 Elsevier B.V.
英文关键词	Deep-tiering infauna; Early Triassic; Ichnodiversity; Microbial mats; Northwestern China; Phase shifts; Unusual biofacies
语种	英语
scopus关键词	benthic infauna; biodiversity; biofacies; ichnology; mass extinction; microbial activity; Triassic; China; Qinghai; Bivalvia; Diplocraterion; Metazoa
来源期刊	EARTH-SCIENCE REVIEWS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/209965
作者单位	State Key Laboratory of Biogeology and Environmental Geology, School of Earth Science, China University of Geosciences (Wuhan), Wuhan, 430074, China; Department of Earth Sciences, University of Southern California, Los Angeles, California, 90089, United States; State Key Laboratory of Geological Process and Mineral Resources, China University of Geosciences (Wuhan), Wuhan, 430074, China; Deakin University, School of Life and Environmental Sciences, Burwood Campus, Melbourne, Victoria 3125, Australia
推荐引用方式 GB/T 7714	Feng X.,Chen Z.-Q.,Bottjer D.J.,et al. Unusual shallow marine matground-adapted benthic biofacies from the Lower Triassic of the northern Paleotethys: Implications for biotic recovery following the end-Permian mass extinction[J],2019,189.
APA	Feng X..,Chen Z.-Q..,Bottjer D.J..,Wu S..,Zhao L..,...&Tu C..(2019).Unusual shallow marine matground-adapted benthic biofacies from the Lower Triassic of the northern Paleotethys: Implications for biotic recovery following the end-Permian mass extinction.EARTH-SCIENCE REVIEWS,189.
MLA	Feng X.,et al."Unusual shallow marine matground-adapted benthic biofacies from the Lower Triassic of the northern Paleotethys: Implications for biotic recovery following the end-Permian mass extinction".EARTH-SCIENCE REVIEWS 189(2019).