气候变化领域集成服务门户(CCPortal): The interaction of recovery and environmental conditions: An analysis of the outer shelf edge of western North America during the early Triassic

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DOI	10.1016/j.palaeo.2018.05.014
	The interaction of recovery and environmental conditions: An analysis of the outer shelf edge of western North America during the early Triassic
	Woods A.D.; Alms P.D.; Monarrez P.M.; Mata S.
发表日期	2019
ISSN	0031-0182
起始页码	52
结束页码	64
卷号	513
英文摘要	Biotic recovery from the Permian-Triassic mass extinction was complex and uneven, with prior studies typically revealing a long, drawn-out recovery that was either delayed for some interval, or was subdued and stepwise in nature. Examples of rapid recovery at the outcrop scale cloud this narrative and point to the importance of environmental stresses in determining the timing and shape of recovery. The Union Wash Formation at the Darwin locality (east-central California) contains at least 3 recovery intervals that terminate with the onset of deleterious conditions and therefore offers a means to examine the relationship between environmental stress and recovery. The first recovery is manifested as bioturbated (ii = 5–6), shallow marine micritic limestones that contain small diameter (2–4 mm) Thalassinoides burrows that form complex networks. This interval is overlain by 650.5 m of laminated mudstone that signal deleterious environmental conditions. The second recovery interval begins directly above seafloor precipitate-bearing micritic limestones that make up the lowermost 130 m of the upper member of the Union Wash Formation and is marked by the occurrence of a 3 m-thick interval containing sphinctozoan sponges, an intervening ~1 m-thick laminated (ii = 1) micritic limestone, and an overlying, 5 m-thick bivalve-rich and bioturbated calcareous siltstone (ii = 4–5) that contains Chrondrites trace fossils. This interval is overlain by 18 m of laminated green shale (ii = 1) that signifies another incursion of anoxic waters. The third recovery interval is represented by a 30 m-thick unit that includes beds of micritic limestone, fossiliferous limestone containing transported fossil grains (including bivalves, microgastropods, sphinctozoan sponges, microgastropods, flat clams, and terebratulid brachiopods), flat pebble conglomerate and vermicular limestone. The results of this study, therefore, point to an uneven recovery within the Union Wash Formation, in which an initially robust recovery in the lower member deteriorated across the remainder of the study section. Areas exposed to persistent environmental stress, therefore, demonstrate protracted and complex recoveries. Study localities located within the habitable zone instead exhibit accelerated recoveries during the post-extinction interval and are indicative of an environmental bias in the form of persistent favorable conditions. The most accurate measures of post – extinction recovery, therefore, are those that examine biotic trends over a broad geographic area, and, as a result, incorporate the role of environmental stress in determining when and how life recovered from the Permian – Triassic mass extinction. © 2018 Elsevier B.V.
英文关键词	Anachronistic facies; Anoxia; Permian – Triassic mass extinction; Thalassinoides; Union wash formation
语种	英语
scopus关键词	anoxic conditions; bioturbation; bivalve; brachiopod; burrow; conglomerate; environmental conditions; environmental stress; facies; gastropod; limestone; marine environment; mass extinction; mudstone; outcrop; Permian-Triassic boundary; recovery; seafloor; shelf break; sponge; trace fossil; California; North America; United States; Bivalvia; Brachiopoda; Sphinctozoa; Terebratulida; Thalassinoides
来源期刊	Palaeogeography, Palaeoclimatology, Palaeoecology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151206
作者单位	Department of Geological Sciences, California State University, Fullerton, 800 N. State College Blvd, Fullerton, CA 92834-6850, United States; Department of Geology, University of Georgia, 210 Field Street, Athens, GA 30602-2501, United States
推荐引用方式 GB/T 7714	Woods A.D.,Alms P.D.,Monarrez P.M.,et al. The interaction of recovery and environmental conditions: An analysis of the outer shelf edge of western North America during the early Triassic[J],2019,513.
APA	Woods A.D.,Alms P.D.,Monarrez P.M.,&Mata S..(2019).The interaction of recovery and environmental conditions: An analysis of the outer shelf edge of western North America during the early Triassic.Palaeogeography, Palaeoclimatology, Palaeoecology,513.
MLA	Woods A.D.,et al."The interaction of recovery and environmental conditions: An analysis of the outer shelf edge of western North America during the early Triassic".Palaeogeography, Palaeoclimatology, Palaeoecology 513(2019).