Challenger Deep basalts reveal Indian-type Early Cretaceous oceanic crust subducting in the southernmost Mariana Trench

doi:10.1130/G51258.1

CORC > 深海科学与工程研究所 > 中国科学院深海科学与工程研究所 > 深海科学研究部 > 深海地质与地球化学研究室

	Challenger Deep basalts reveal Indian-type Early Cretaceous oceanic crust subducting in the southernmost Mariana Trench
	Xu, Wenjing 3; Peng, Xiaotong 3; Stern, Robert J.; Xu, Xisheng 1,2; Xu, Hengchao 3
刊名	GEOLOGY
	2023-09-01
卷号	51 期号:9 页码:865-869
ISSN号	0091-7613
DOI	10.1130/G51258.1
通讯作者	Peng, Xiaotong(xtpeng@idsse.ac.cn)
英文摘要	Why the Challenger Deep, the deepest point on Earth's solid surface, is so deep is unclear, but part of the reason must be the age and density of the downgoing plate. Northwest Pacific oceanic crust subducting in the Izu-Bonin-Mariana Trench is Cretaceous and Jurassic, but the age and nature of Pacific oceanic crust subducting in the southernmost Mariana Trench remains unknown. Here we present the first study of seafloor basalts recovered by the fullocean-depth crewed submersible Fendouzhe from the deepest seafloor around the Challenger Deep, from both the overriding and downgoing plates. 40Ar/39Ar ages indicate that downgoing basalts are Early Cretaceous (ca. 125 Ma), indicating they are part of the Pacific plate rather than the nearby Oligocene Caroline microplate. Downgoing-plate basalts are slightly enriched in incompatible elements but have similar trace element and Hf isotope compositions to other northwest Pacific mid-ocean ridge basalts (MORBs). They also have slightly enriched Sr-Nd-Pb isotope compositions like those of the Indian mantle domain. These features may have formed with contributions from plume-derived components via plume-ridge interactions. One sample from the overriding plate gives an 40Ar/39Ar age of ca. 55 Ma, about the same age as subduction initiation, to form the Izu-Bonin-Mariana convergent margin. Our results suggest that 50%-90% of the Pb budget of Mariana arc magmas is derived from the subducted MORBs with Indian-type isotope affinity.
资助项目	National Key R&D Program of China[2016YFC0300503] ; National Key R&D Program of China[2016YFC0300600] ; National Key R&D Program of China[2017YFC0306604] ; National Key R&D Program of China[2018YFC0309802] ; National Key R&D Program of China[2022YFF0800404]
WOS关键词	ELEMENT ; MANTLE ; SCALE ; SIGNATURE ; ORIGIN ; FLUIDS
WOS研究方向	Geology
语种	英语
出版者	GEOLOGICAL SOC AMER, INC
WOS记录号	WOS:001108906300002
资助机构	National Key R&D Program of China
内容类型	期刊论文
源URL	[http://ir.idsse.ac.cn/handle/183446/10716]
专题	深海科学研究部_深海地质与地球化学研究室
通讯作者	Peng, Xiaotong
作者单位	1.Nanjing Univ, Sch Earth Sci & Engn, State Key Lab Mineral Deposits Res, Nanjing 210023, Peoples R China 2.Univ Texas Dallas, Dept Geosci, Richardson, TX 75080 USA 3.Chinese Acad Sci, Inst Deep Sea Sci & Engn, Deep Sea Sci Div, Sanya 572000, Peoples R China
推荐引用方式 GB/T 7714	Xu, Wenjing,Peng, Xiaotong,Stern, Robert J.,et al. Challenger Deep basalts reveal Indian-type Early Cretaceous oceanic crust subducting in the southernmost Mariana Trench[J]. GEOLOGY,2023,51(9):865-869.
APA	Xu, Wenjing,Peng, Xiaotong,Stern, Robert J.,Xu, Xisheng,&Xu, Hengchao.(2023).Challenger Deep basalts reveal Indian-type Early Cretaceous oceanic crust subducting in the southernmost Mariana Trench.GEOLOGY,51(9),865-869.
MLA	Xu, Wenjing,et al."Challenger Deep basalts reveal Indian-type Early Cretaceous oceanic crust subducting in the southernmost Mariana Trench".GEOLOGY 51.9(2023):865-869.