干旱区生态环境知识资源中心(Arid): Testing local and extraregional sediment sources for the Late Cretaceous northern Nanaimo basin, British Columbia, using Ar-40/Ar-39 detrital K-feldspar thermochronology

Arid

DOI	10.1130/GES02395.1
	Testing local and extraregional sediment sources for the Late Cretaceous northern Nanaimo basin, British Columbia, using Ar-40/Ar-39 detrital K-feldspar thermochronology
	Isava, V; Grove, M.; Mahoney, J. B.; Haggart, J. W.
通讯作者	Isava, V (corresponding author), Stanford Univ, Dept Geol Sci, 450 Jane Stanford Way,Bldg 320,Room 118, Stanford, CA 94305 USA.
来源期刊	GEOSPHERE
ISSN	1553-040X
出版年	2021
卷号	17 期号:6 页码:2234-2261
英文摘要	Detrital K-feldspar Ar-40/Ar-39 thermochronology was conducted on clastic sedimentary rock samples collected from northern exposures of the Upper Cretaceous Nanaimo Group on Vancouver Island and adjacent Gulf Islands of British Columbia to constrain the denudation history of the local Coast Mountains batholith source region and determine the origin of extraregional sediment supplied to the basin. Strata of the northern Nanaimo Group deposited between 86 and 83 Ma (Comox and Extension formations) exhibit a 130-85 Ma age distribution of detrital K-feldspar Ar-40/Ar-39 ages that lack age maxima. These are interpreted to have been sourced from the southwestern Coast Mountains batholith. Younger strata deposited between 83 and 72 Ma (Cedar District and De Courcy formations) yield a broader age range (150-85 Ma) with an age maximum near the depositional age. These results indicate focused denudation of deeper-seated rocks east of the Harrison Lake fault. The youngest units deposited after 72 Ma (Geoffrey, Spray, and Gabriola formations) primarily yield younger than 75 Ma detrital K-feldspar ages with pronounced age maxima near the depositional age. This sediment was sourced extraregionally relative to the Coast Mountains batholith. We sought to constrain the origin of the extraregional sediment by measuring the thermal histories of 74 samples of basement rocks from throughout the Pacific Northwest, and by compiling a database of over 2400 biotite Ar-40/Ar-39 and K/Ar cooling ages from predominantly Cretaceous batholiths along the western North American margin. This analysis focused upon two previously proposed source regions: the Idaho batholith and the Mojave-Salina margin of southern California. The Nanaimo detrital K-feldspar Ar-40/Ar-39 age distributions favor the peraluminous Late Cretaceous Idaho batholith and its Proterozoic Belt-Purcell Supergroup sedimentary wall rock as the more likely source of the extraregional sediment and disfavor the Baja-British Columbia hypothesis for 2000-4000-km-scale translation of rocks along the margin during the Late Cretaceous.
类型	Article
语种	英语
开放获取类型	Green Submitted, gold
收录类别	SCI-E
WOS记录号	WOS:000726728000005
WOS关键词	COAST PLUTONIC COMPLEX ; U-PB ZIRCON ; SIERRA-NEVADA BATHOLITH ; MOJAVE DESERT REGION ; DEXTRAL STRIKE-SLIP ; SAN-JUAN ISLANDS ; FORE-ARC BASIN ; VANCOUVER-ISLAND ; TECTONIC EVOLUTION ; UNITED-STATES
WOS类目	Geosciences, Multidisciplinary
WOS研究方向	Geology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/374015
作者单位	[Isava, V; Grove, M.] Stanford Univ, Dept Geol Sci, 450 Jane Stanford Way,Bldg 320,Room 118, Stanford, CA 94305 USA; [Mahoney, J. B.] Univ Wisconsin, Dept Geol, 149 Phillips Sci Hall, Eau Claire, WI 54701 USA; [Haggart, J. W.] Geol Survey Canada Pacific, 1500-605 Robson St, Columbia, BC V6B 5J3, Canada
推荐引用方式 GB/T 7714	Isava, V,Grove, M.,Mahoney, J. B.,et al. Testing local and extraregional sediment sources for the Late Cretaceous northern Nanaimo basin, British Columbia, using Ar-40/Ar-39 detrital K-feldspar thermochronology[J],2021,17(6):2234-2261.
APA	Isava, V,Grove, M.,Mahoney, J. B.,&Haggart, J. W..(2021).Testing local and extraregional sediment sources for the Late Cretaceous northern Nanaimo basin, British Columbia, using Ar-40/Ar-39 detrital K-feldspar thermochronology.GEOSPHERE,17(6),2234-2261.
MLA	Isava, V,et al."Testing local and extraregional sediment sources for the Late Cretaceous northern Nanaimo basin, British Columbia, using Ar-40/Ar-39 detrital K-feldspar thermochronology".GEOSPHERE 17.6(2021):2234-2261.