气候变化领域集成服务门户(CCPortal): Isotopes to ice: Constraining provenance of glacial deposits and ice centers in west-central Gondwana

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DOI	10.1016/j.palaeo.2018.04.020
	Isotopes to ice: Constraining provenance of glacial deposits and ice centers in west-central Gondwana
	Griffis N.P.; Montañez I.P.; Fedorchuk N.; Isbell J.; Mundil R.; Vesely F.; Weinshultz L.; Iannuzzi R.; Gulbranson E.; Taboada A.; Pagani A.; Sanborn M.E.; Huyskens M.; Wimpenny J.; Linol B.; Yin Q.-Z.
发表日期	2019
ISSN	0031-0182
卷号	531
英文摘要	The timing and geographic distribution of glaciers in high-latitude southern Gondwana during the Late Paleozoic Ice Age remain poorly constrained, ultimately precluding our ability to estimate ice volume and associated climate teleconnections and feedbacks during Earth's penultimate icehouse. Current aerial extents of glaciers, constrained by sedimentary flow directions, near exclusively infer paleo-glaciation to be highland-driven and may underestimate potential ice sources in continental regions from which ice sheets may have emanated. Here, we report new U-Pb ages and Hf isotope compositions of detrital zircons recovered from diamictites in two key mid- to high-latitude Gondwanan basins (Paraná, Brazil and Tepuel, Argentine Patagonia). The results indicate regional sediment sources for both basins during the early period of late Paleozoic glaciation evolving into more distal sources during the final deglaciation along southern and western Gondwana. Similar age sediment sourced from diamictites in the Congo Basin, that require an ice center in eastern Africa suggest the possibility of a large ice sheet in this area of Africa proximal to the Carboniferous-Permian boundary, which may have sourced sediments to the Paraná Basin. An inferred distal southern source of glacial sediment for the Tepuel Basin argues for the presence of an ice sheet(s) in the Ellsworth Block of Antarctica towards the end of the glaciation history in Patagonia. These findings indicate an evolution during the Late Paleozoic Ice Age from proximally to extrabasinally sourced sediment reflecting continental-scale glaciation and subsequent drainage from the Windhoek Highlands, Ellsworth Block and an east African source in west-central Gondwana. Coincidence with a long-term fall in atmospheric pCO2 during the Pennsylvanian to a minimum across the Carboniferous-Permian boundary and a subsequent rise in the early Permian suggests a primary CO2-driver for deglaciation in the Paraná Basin. Additional boundary conditions including availability of moisture and paleogeography likely further contributed to the timing of nucleation, growth and demise of these Gondwanan glaciers. © 2018 Elsevier B.V.
英文关键词	Detrital zircon; Glaciation; Ice sheet; LPIA; Provenance
语种	英语
scopus关键词	boundary condition; Carboniferous; detrital deposit; glacial deposit; glaciation; ice sheet; isotopic composition; paleogeography; Pleistocene; uranium-lead dating; zircon; Antarctica; Brazil; Congo Basin; Khomas; Namibia; Parana [Brazil]; Patagonia; Windhoek
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/150880
作者单位	University of California, Davis, Davis, CA, United States; University of Wisconsin, Milwaukee, Milwaukee, WI, United States; Berkeley Geochronology Center, Berkeley, CA, United States; Universidade Federal do Paraná, Curitiba, Brazil; Universidade do Contestado, Mafra - CENPÁLEOSanta Catarina, Brazil; Universidade Federal Rio Grande do Sul, Porto Alegre, Brazil; CIEMEP, CONICET-UNPSJB, Esquel, Chubut, Argentina; Museo Paeontológico Egidio Feruglio - CONICETChubut, Argentina; Nelson Mandela Metropolitan University, Port Elizabeth, South Africa
推荐引用方式 GB/T 7714	Griffis N.P.,Montañez I.P.,Fedorchuk N.,et al. Isotopes to ice: Constraining provenance of glacial deposits and ice centers in west-central Gondwana[J],2019,531.
APA	Griffis N.P..,Montañez I.P..,Fedorchuk N..,Isbell J..,Mundil R..,...&Yin Q.-Z..(2019).Isotopes to ice: Constraining provenance of glacial deposits and ice centers in west-central Gondwana.Palaeogeography, Palaeoclimatology, Palaeoecology,531.
MLA	Griffis N.P.,et al."Isotopes to ice: Constraining provenance of glacial deposits and ice centers in west-central Gondwana".Palaeogeography, Palaeoclimatology, Palaeoecology 531(2019).