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DOI	10.1016/j.epsl.2020.116123
	Geochemistry of Etendeka magmatism: Spatial heterogeneity in the Tristan-Gough plume head
	Zhou H.; Hoernle K.; Geldmacher J.; Hauff F.; Homrighausen S.; Garbe-Schönberg D.; Jung S.
发表日期	2020
ISSN	0012821X
卷号	535
英文摘要	The origin and distribution of geochemically distinct source components in continental flood volcanism (generally associated with the initial phase of a mantle plume head) are poorly understood. Here we present new geochemical (major and trace element and Sr-Nd-Pb-Hf isotope) data from the Etendeka flood basalts and associated dikes from northern and central Namibia that are believed to have been produced during the initial stage of the Tristan-Gough hotspot. Following earlier studies, the Etendeka lava flows and dikes are divided into high-Ti and low-Ti groups. The trace element and isotopic composition of the high-Ti tholeiitic basalts, exclusively outcropping in northern Etendeka (northwestern Namibia), are similar to the Gough-type enriched mantle I (EMI) composition found on the Walvis Ridge (the Atlantic type locality for the EMI end member). The low-Ti tholeiitic basalts, primarily outcropping in Southern Etendeka (central western Namibia), have higher 143Nd/144Nd and 207Pb/204Pb but lower 208Pb/204Pb ratios than the Gough composition. Combining our data with newly published 3He/4He data and estimates of the magma source's potential temperature from 1520-1680°C, we conclude that the source of the low-Ti basalts was also intrinsic to the Tristan-Gough plume, consistent with a spatially-zoned plume head. The low-Ti basalts were derived from a distinct EMI-type source component that has thus far only been detected in the initial Tristan-Gough plume head (∼132 Ma), but not the later submarine hotspot track. © 2020 Elsevier B.V.
关键词	Etendeka flood basalts Gough Large Igneous Province (LIP)Namibia plume zonation Sr-Nd-Pb-Hf isotope ratios
英文关键词	Basalt; Floods; Geochemistry; Hafnium alloys; Isotopes; Levees; Neodymium alloys; Strontium alloys; Trace elements; Flood basalt; Gough; Large igneous provinces; Namibia; plume zonation; Sr-Nd-Pb-Hf isotopes; Lead alloys; flood basalt; hafnium; hot spot; igneous geochemistry; large igneous province; lava flow; lead isotope; magmatism; neodymium isotope; strontium isotope; Namibia
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/203009
作者单位	GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, Kiel, 24148, Germany; Institute of Geosciences, Kiel University, Ludewig-Meyn-Str. 10, Kiel, 24118, Germany; Institute of Mineralogy and Petrography, Universität Hamburg, Grindelallee 48, Hamburg, 20146, Germany
推荐引用方式 GB/T 7714	Zhou H.,Hoernle K.,Geldmacher J.,et al. Geochemistry of Etendeka magmatism: Spatial heterogeneity in the Tristan-Gough plume head[J],2020,535.
APA	Zhou H..,Hoernle K..,Geldmacher J..,Hauff F..,Homrighausen S..,...&Jung S..(2020).Geochemistry of Etendeka magmatism: Spatial heterogeneity in the Tristan-Gough plume head.Earth and Planetary Science Letters,535.
MLA	Zhou H.,et al."Geochemistry of Etendeka magmatism: Spatial heterogeneity in the Tristan-Gough plume head".Earth and Planetary Science Letters 535(2020).