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DOI	10.1130/B35673.1
	Large-scale asymmetry in thickness of crustal accretion at the Southeast Indian Ridge due to deep mantle anomalies
	Suo Y.; Li S.; Cao X.
发表日期	2021
ISSN	167606
起始页码	1057
结束页码	1070
卷号	133 期号:2021-05-06
英文摘要	Hot mantle plumes and ancient cold slabs have been observed beneath modern midocean ridges, but their specific and detailed effects on mid-ocean ridge crustal accretion are poorly understood. The oceanic lithosphere beneath the Southeast Indian Ocean displays unique morphological, geophysical, and geochemical characteristics, which may reflect the influence of both mantle anomalies and upwelling plumes on seafloor spreading. In this study, we combined gravity-derived oceanic crustal thickness with plate tectonic reconstructions to investigate patterns of asymmetry in thickness of crust accreted at the Southeast Indian Ridge over the last 50 m.y. Our results reveal several distinct features: (1) small-scale, short-lived asymmetries in the thickness of crustal accretion of up to 0.75 km are alternatively distributed on the southern and northern flanks of the 90°-120°E Southeast Indian Ridge segment. These can be explained by variations in mantle depletion or mantle temperature. (2) Two large-scale, long-lived (duration of -50 m.y.) asymmetries in crustal accretion of >2.5 km are observed around the Kerguelen Plateau and Balleny Islands, which we attribute to excess crust from the off-axis Kerguelen and Balleny mantle plumes. (3) Two large-scale, long-lived (duration of -50 m.y.) asymmetries in crustal accretion of 0.75-2.5 km are observed on the northern flank of the westernmost (70°-80°E) Southeast Indian Ridge and the southern flank of the eastern (120°-140°E) Southeast Indian Ridge segment, respectively. We attribute these to asymmetry in mantle temperature of up to 20-53 °C. We suggest these asymmetric temperatures across the Southeast Indian Ridge are asso- ciated with the foundered lithospheric fragments of the Indian Craton triggered by the African Large Low-Shear-Velocity Province during the breakup of Gondwanaland and an intraplate subducted slab of the PaleoTethys Ocean, respectively. The remnant craton fragments and subducted oceanic slab may have moved north in concert with the northward-migrating Southeast Indian Ridge beginning at 50 m.y. ago. © 2021 Geological Society of America. All Rights Reserved.
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/184684
作者单位	Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Lab of Submarine Geosciences and Prospecting Techniques, MOE, College of Marine Geosciences, Ocean University of China, Qingdao, 266100, China; Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266100, China; EarthByte Group, School of Geosciences, The University of Sydney, Sydney, New South Wales 2006, Australia
推荐引用方式 GB/T 7714	Suo Y.,Li S.,Cao X.. Large-scale asymmetry in thickness of crustal accretion at the Southeast Indian Ridge due to deep mantle anomalies[J],2021,133(2021-05-06).
APA	Suo Y.,Li S.,&Cao X..(2021).Large-scale asymmetry in thickness of crustal accretion at the Southeast Indian Ridge due to deep mantle anomalies.Bulletin of the Geological Society of America,133(2021-05-06).
MLA	Suo Y.,et al."Large-scale asymmetry in thickness of crustal accretion at the Southeast Indian Ridge due to deep mantle anomalies".Bulletin of the Geological Society of America 133.2021-05-06(2021).