Global volcanic arc magma composition correlates with thickness of both arc crust (Moho depth) and arc lithosphere (LAB depth): A revealing message on arc basement histories and arc magmatism

doi:10.1016/j.gsf.2023.1016091674-9871/e2023

IOCAS-IR

	Global volcanic arc magma composition correlates with thickness of both arc crust (Moho depth) and arc lithosphere (LAB depth): A revealing message on arc basement histories and arc magmatism
	Mazuir, R. A. Balqis ; Niu, Yaoling 1,2,3,4
	2023-09-01
发表期刊	GEOSCIENCE FRONTIERS
ISSN	1674-9871
卷号	14 期号:5 页码:12
通讯作者	Niu, Yaoling(yaoling.niu@foxmail.com)
摘要	Past fifty years have seen mounting publications on the genesis of volcanic arc magmas. While details remain debated, it is generally agreed that arc magmas result from slab-dehydration induced mantle wedge melting followed by crustal level differentiation of varying extent and sophistication. Two recent arc magma studies deserve particular attention because they attempt to discuss globally unifying con-trols on arc magma composition. Both Harvard study (Turner and Langmuir, 2015a,b) and Rice study (Farner and Lee, 2017) show correlations of arc magma composition with crustal thickness and both ascribe the crustal thickness as the principal control on their observed magma compositional variations, yet the physical role of the crustal thickness in their interpretations is markedly different because of (1) the ambiguous use of "crust" and (2) their different magma compositional ranges chosen in discus-sion. The Harvard study only uses basaltic samples corrected to MgO = 6.0 wt.% to discuss mantle pro-cesses and interprets the arc crustal thickness as restricting the mantle wedge melting, i.e., the extent of melting decreases with increasing crustal thickness. The Rice study uses samples of all compositions (basaltic to rhyolitic), whose extent of differentiation increases with increasing crustal thickness, inter-preted as Moho-crossing mantle wedge melts travelling greater vertical distance with greater degree of cooling and erupting more evolved compositions above thicker crust than melts erupted above thinner crust without need of invoking mantle wedge processes. We commend these efforts and approve their different approaches but emphasize that the unifying understanding of global arc magmatism requires clearly defined Moho (the base of the crust) and LAB (the lithosphere-asthenosphere boundary) and their intrinsic controls on mantle wedge melting (Harvard Study model) and crustal level magma differentia-tion (Rice Study model) beneath global arcs. In this study, we use chemical compositions of 36,945 global arc volcanic samples provided by the Rice study together with the literature data on seismic Moho and LAB depths of these sample locations to establish (1) the correlation of crustal thickness interval averaged magma composition with crustal thickness and (2) the correlation of lithosphere thickness interval aver-aged magma composition with lithosphere thickness. These correlations reaffirm our understanding that the lithospheric mantle must exist beneath volcanic arc crust with a globally averaged LAB/Moho depth ratio of 3.26 +/- 0.63, i.e., the arc crust is on average about 31.8% +/- 6.1% of the lithosphere thickness. This knowledge forms a solid constraint essential for models of global arc magmatism. (c) 2023 CHINA UNIVERSITY OF GEOSCIENCES (BEIJING) and PEKING UNIVERSITY. Published by Elsevier B.V. on behalf of China University of Geosciences (Beijing). This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
关键词	Global volcanic arc magma compositions Arc crustal thickness Arc lithospheric thickness Moho-LAB depth correlation Flux melting for diapirs Diapiric decompression melting
DOI	10.1016/j.gsf.2023.1016091674-9871/e2023
收录类别	SCI
语种	英语
资助项目	NSFC[B18048] ; 111 Project ; [91958215]
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000984543200001
出版者	CHINA UNIV GEOSCIENCES, BEIJING
WOS关键词	ISLAND BASALTS OIB ; SUBDUCTION ZONES ; ELEMENT TRANSPORT ; CONTINENTAL-CRUST ; GEOCHEMISTRY ; EVOLUTION ; VELOCITY ; FRONT ; CHEMISTRY ; ORIGIN
引用统计
文献类型	期刊论文
条目标识符	http://ir.qdio.ac.cn/handle/337002/183057
专题	中国科学院海洋研究所
通讯作者	Niu, Yaoling
作者单位	1.Univ Durham, Durham DH1 3LE, England 2.Laoshan Lab, Qingdao 266237, Peoples R China 3.China Univ Geosci Beijing, Beijing 100083, Peoples R China 4.Inst Oceanol, Qingdao 266071, Peoples R China
通讯作者单位	中国科学院海洋研究所
推荐引用方式 GB/T 7714	Mazuir, R. A. Balqis,Niu, Yaoling. Global volcanic arc magma composition correlates with thickness of both arc crust (Moho depth) and arc lithosphere (LAB depth): A revealing message on arc basement histories and arc magmatism[J]. GEOSCIENCE FRONTIERS,2023,14(5):12.
APA	Mazuir, R. A. Balqis,&Niu, Yaoling.(2023).Global volcanic arc magma composition correlates with thickness of both arc crust (Moho depth) and arc lithosphere (LAB depth): A revealing message on arc basement histories and arc magmatism.GEOSCIENCE FRONTIERS,14(5),12.
MLA	Mazuir, R. A. Balqis,et al."Global volcanic arc magma composition correlates with thickness of both arc crust (Moho depth) and arc lithosphere (LAB depth): A revealing message on arc basement histories and arc magmatism".GEOSCIENCE FRONTIERS 14.5(2023):12.