Different effects of serpentinite-derived and slab-derived fluids on arc magmatism in the Chinese Eastern Tianshan: evidence from Mg-B isotopic systematics

doi:10.1144/jgs2023-011

	Different effects of serpentinite-derived and slab-derived fluids on arc magmatism in the Chinese Eastern Tianshan: evidence from Mg-B isotopic systematics
	Du, Long 1,2; Zhang, Yunying 3; Zhu, Hongli4 ; Zhang, Zhaofeng 5; An, Yajun 5; Yuan, Chao 6; Huang, Zongying 6; Li, Xuping 1; Long, Xiaoping 2
	2023-09-29
发表期刊	JOURNAL OF THE GEOLOGICAL SOCIETY
ISSN	0016-7649
卷号	180 期号:5 页码:10
通讯作者	Long, Xiaoping(longxp@nwu.edu.cn)
摘要	Fluids are important media for elemental cycling in subduction zones, but the compositions of such fluids remain obscure, especially those derived from dehydration of serpentinite. To better understand the role of subduction-zone fluids in arc magmatism of the Chinese Eastern Tianshan (CET), we present Mg and B isotopic data for the arc diorites (e.g. Kalatage and Nanshankou). Our results show that the Kalatage diorites have higher delta Mg-26 (-0.23 to -0.13 parts per thousand) and delta B-11 (-0.04 to +1.08 parts per thousand) values than the corresponding mantle values, whereas the Nanshankou diorites display relatively lower delta Mg-26 (-0.26 to -0.19 parts per thousand ) and 811B (-10.7 to -2.97 parts per thousand) values. Because high-temperature magmatic and post-magmatic processes have limited effects on Mg and B isotope fractionation of our samples, their distinct Mg-B isotopic signatures inherited from the mantle sources should be caused by subduction-related metasomatism. Because neither altered oceanic crust (AOC) directly melting nor the incorporation of subducted sediments could induce significant Mg-B isotope fractionation in these rocks, we infer that their variable delta Mg-26 and delta B-11 values were probably associated with subduction fluids that were derived from different sources. Specifically, dehydrated fluids from serpentinites possess high delta Mg-26 and delta B-11 values, which resulted in the heavy Mg-B isotopic compositions of the Kalatage diorites, whereas mantle metasomatized by fluids from AOC and subducted sediments were responsible for the Nanshankou rocks with relatively low delta Mg-26 and delta B-11 values. Taking into account the different effects of serpentinite-derived and slab-derived fluids in the formation of arc magmatism, subduction-zone fluids can be probably an important factor in changing the Mg-B isotope composition of mantle sources.
DOI	10.1144/jgs2023-011
收录类别	SCI
语种	英语
资助项目	We thank Jinlong Ma and Le Zhang for their help with the geochemical analyses.
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:001079766600013
出版者	GEOLOGICAL SOC PUBL HOUSE
WOS关键词	BORON ISOTOPE ; SUBDUCTION ZONES ; OROGENIC BELT ; MANTLE WEDGE ; FORE-ARC ; GRANITOIDS ; FRACTIONATION ; CONSTRAINTS ; LAVAS ; HETEROGENEITY
引用统计
文献类型	期刊论文
条目标识符	http://ir.qdio.ac.cn/handle/337002/181553
专题	深海极端环境与生命过程研究中心
通讯作者	Long, Xiaoping
作者单位	1.Shandong Univ Sci & Technol, Coll Earth Sci & Engn, Res Ctr Continental Dynam, Qingdao 266590, Peoples R China 2.Northwest Univ, Dept Geol, State Key Lab Continental Dynam, Xian 710069, Peoples R China 3.Chinese Acad Sci, South China Sea Inst Oceanol, Key Lab Ocean & Marginal Sea Geol, Innovat Acad South China Sea Ecol & Environm Engn, Guangzhou 510301, Peoples R China 4.Chinese Acad Sci, Ctr Deep Sea Res, Inst Oceanog, Qingdao 266071, Peoples R China 5.Chengdu Univ Technol, Coll Earth Sci, Int Ctr Planetary Sci, Chengdu 610059, Peoples R China 6.Chinese Acad Sci, Guangzhou Inst Geochem, State Key Lab Isotope Geochem, Guangzhou 510640, Peoples R China
推荐引用方式 GB/T 7714	Du, Long,Zhang, Yunying,Zhu, Hongli,et al. Different effects of serpentinite-derived and slab-derived fluids on arc magmatism in the Chinese Eastern Tianshan: evidence from Mg-B isotopic systematics[J]. JOURNAL OF THE GEOLOGICAL SOCIETY,2023,180(5):10.
APA	Du, Long.,Zhang, Yunying.,Zhu, Hongli.,Zhang, Zhaofeng.,An, Yajun.,...&Long, Xiaoping.(2023).Different effects of serpentinite-derived and slab-derived fluids on arc magmatism in the Chinese Eastern Tianshan: evidence from Mg-B isotopic systematics.JOURNAL OF THE GEOLOGICAL SOCIETY,180(5),10.
MLA	Du, Long,et al."Different effects of serpentinite-derived and slab-derived fluids on arc magmatism in the Chinese Eastern Tianshan: evidence from Mg-B isotopic systematics".JOURNAL OF THE GEOLOGICAL SOCIETY 180.5(2023):10.