气候变化领域集成服务门户(CCPortal): Trace element-enriched mid-visean dikes in the New Carlisle area of Quebec, Canada: Unusual products of a tholeiitic melt sourced from metasomatized mantle rocks and fractionated in a brine-rich upper-crustal environment

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DOI	10.1130/B35206.1
	Trace element-enriched mid-visean dikes in the New Carlisle area of Quebec, Canada: Unusual products of a tholeiitic melt sourced from metasomatized mantle rocks and fractionated in a brine-rich upper-crustal environment
	Jutras P.; Dostal J.; Kamo S.
发表日期	2019
ISSN	167606
起始页码	2079
结束页码	2093
卷号	131 期号:2021-11-12
英文摘要	Early Carboniferous tholeiitic dikes in the New Carlisle area of Quebec, Canada, are abnormally enriched in high field strength elements (HFSEs), including rare earth elements. The enrichment is systematic and was apparently caused by an enhanced incompatibility of HFSEs during a prolonged episode of crystal fractionation. As a result, HFSE concentrations are up to one order of magnitude higher than those of typical mafic rocks. Very high F and Cl contents suggest that halogen complexing was largely responsible for the trace-element enrichment. The high halogen contents are in part accounted for by a subcontinental lithospheric mantle source that had previously been enriched in these elements by prolonged subduction. Additional Cl enrichment is interpreted to have occurred in a magma chamber that developed within porous and brine-rich country rocks of the upper crust. This conclusion is supported by the observation that HFSE-enriched mafic plutons in the same magmatic province occur in nonmetamorphosed upper-crustal rocks, suggesting high buoyancy and therefore high temperatures. Such evidence for high heat in the late Paleozoic magmatic system of eastern Canada corroborates previous studies suggesting that the transtensional basin in which it evolved was overriding a mantle plume at the time. In the case of the New Carlisle dikes, which are more than twice as enriched in incompatible trace elements as slightly older mafic rocks of the same magmatic system, the regional paleoenvironmental setting suggests that the associated upper-crustal magma chamber may have evolved in rocks with saltier pore water due to long-lasting evaporitic conditions at the surface. © 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/184951
作者单位	Department of Geology, Saint Mary's University, Halifax, NS B3H 3C3, Canada; Department of Earth Sciences, University of Toronto, 22 Russell Street, Toronto, ON M5S 3B1, Canada
推荐引用方式 GB/T 7714	Jutras P.,Dostal J.,Kamo S.. Trace element-enriched mid-visean dikes in the New Carlisle area of Quebec, Canada: Unusual products of a tholeiitic melt sourced from metasomatized mantle rocks and fractionated in a brine-rich upper-crustal environment[J],2019,131(2021-11-12).
APA	Jutras P.,Dostal J.,&Kamo S..(2019).Trace element-enriched mid-visean dikes in the New Carlisle area of Quebec, Canada: Unusual products of a tholeiitic melt sourced from metasomatized mantle rocks and fractionated in a brine-rich upper-crustal environment.Bulletin of the Geological Society of America,131(2021-11-12).
MLA	Jutras P.,et al."Trace element-enriched mid-visean dikes in the New Carlisle area of Quebec, Canada: Unusual products of a tholeiitic melt sourced from metasomatized mantle rocks and fractionated in a brine-rich upper-crustal environment".Bulletin of the Geological Society of America 131.2021-11-12(2019).