气候变化领域集成服务门户(CCPortal): Upper Windermere Supergroup and the transition from rifting to continentmargin sedimentation, Nadaleen River area, northern Canadian Cordillera

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DOI	10.1130/B32039.1
	Upper Windermere Supergroup and the transition from rifting to continentmargin sedimentation, Nadaleen River area, northern Canadian Cordillera
	Moynihan D.P.; Strauss J.V.; Nelson L.L.; Padget C.D.
发表日期	2019
ISSN	167606
起始页码	1673
结束页码	1701
卷号	131 期号:2021-09-10
英文摘要	Neoproterozoic-Cambrian rocks of the Windermere Supergroup and overlying units record the breakup of Rodinia and formation of the northwestern Laurentian ancestral continental margin. Understanding the nature and timing of this transition has been hampered by difficulty correlating poorly dated sedimentary successions from contrasting depositional settings across Mesozoic structures. Here we present new lithoand chemo-stratigraphic data from a Cryogenian- lower Cambrian succession in east-central Yukon (Canada), establish correlations between proximal and distal parts of the upper Windermere Supergroup and related strata in the northern Canadian Cordillera, and consider implications for the formation of the northwestern Laurentian margin. The newly defined Nadaleen Formation hosts the first appearance of Ediacaran macrofossils, while the overlying Gametrail Formation features a large negative carbon isotope anomaly with δ13Ccarb values as low as -13‰ that correlates with the globally developed Shuram-Wonoka anomaly. We also define the Rackla Group, which includes the youngest (Ediacaran) portions of the Windermere Supergroup in the northern Cordillera. The top of the Windermere Supergroup is marked by an unconformity above the Risky Formation that passes into a correlative conformity in the Nadaleen River area. This surface has been interpreted to mark the top of the rift-related succession, but we draw attention to evidence for tectonic instability through the early-middle Cambrian and argue that the transition from rifting to postrift thermal subsidence is marked by a widespread unconformity that underlies upper Cambrian carbonate rocks. This is younger than the interpreted age of the rift to postrift transition elsewhere along the ancestral western Laurentian continental margin. © 2019 Geological Society of America.
语种	英语
来源期刊	Bulletin of the Geological Society of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/184893
作者单位	Yukon Geological Survey, P.O. Box 2703, Whitehorse, YT Y1A 2C6, Canada; Department of Earth Sciences, Dartmouth College, HB6105 Fairchild Hall, Hanover, NH 03755, United States; Department of Earth and Planetary Sciences, Johns Hopkins University, 3400 N. Charles Street, Olin Hall, Baltimore, MD 21218, United States; Department of Geoscience, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
推荐引用方式 GB/T 7714	Moynihan D.P.,Strauss J.V.,Nelson L.L.,et al. Upper Windermere Supergroup and the transition from rifting to continentmargin sedimentation, Nadaleen River area, northern Canadian Cordillera[J],2019,131(2021-09-10).
APA	Moynihan D.P.,Strauss J.V.,Nelson L.L.,&Padget C.D..(2019).Upper Windermere Supergroup and the transition from rifting to continentmargin sedimentation, Nadaleen River area, northern Canadian Cordillera.Bulletin of the Geological Society of America,131(2021-09-10).
MLA	Moynihan D.P.,et al."Upper Windermere Supergroup and the transition from rifting to continentmargin sedimentation, Nadaleen River area, northern Canadian Cordillera".Bulletin of the Geological Society of America 131.2021-09-10(2019).