气候变化领域集成服务门户(CCPortal): Eocene pre- and syn-obduction tectonics in New Caledonia (Southwest Pacific), a case for oblique subduction, transcurrent tectonics and oroclinal bending; structural and paleomagnetic evidence

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DOI	10.1016/j.tecto.2021.228875
	Eocene pre- and syn-obduction tectonics in New Caledonia (Southwest Pacific), a case for oblique subduction, transcurrent tectonics and oroclinal bending; structural and paleomagnetic evidence
	Dominique C.; Marion I.; Yan C.
发表日期	2021
ISSN	00401951
卷号	811
英文摘要	The structural analysis of the metamorphic belt and allochthonous terranes, which represent the lower and upper plates of the Eocene subduction/obduction complex of New Caledonia respectively, unravels a multi-step evolution. At subduction inception, the originally N-S trending northern Norfolk/New Caledonia Ridge was moving northward as recorded by sheared lower Eocene dykes of the Peridotite Nappe. Fast exhumation of the fore-arc mantle in transtensional conditions was recorded by the injection of fore-arc magmas through fast-cooling peridotites, followed by the occurrence of antigorite- and tremolite-bearing crack seals in small-scale transcurrent or oblique-slip faults. Meanwhile, slices of the oceanic crust of the lower plate were scrapped off and accumulated in the fore-arc region while some elements were dragged down into the subduction zone and contributed to the formation of eclogite facies mélange. When the tip of the New Caledonia Ridge reached the trench, it progressively jammed the subduction. Meanwhile, the oblique slip and coeval rotation of the arc due to the opening of the north Loyalty back-arc basin provoked the dextral transcurrent folding of already accreted ocean crust slices and metamorphic units on the course of exhumation. Bulk counterclockwise rotation of 56° ± 5° was recorded in the foreland basin by paleomagnetic data of sediments from the 45–35 Ma time interval. The final obduction of fore-arc peridotites occurred with top-to-the-SW kinematics when the island had already reached its present orientation. © 2021 Elsevier B.V.
关键词	fault analysis Oblique subduction oroclinal bending paleomagnetism supra-subduction dykes transcurrent folding
英文关键词	Kaolinite; Metamorphic rocks; Serpentine; Tectonics; Counter clockwise rotation; Fore arc region; Metamorphic belts; Multi-step evolutions; Oblique subduction; Paleomagnetic data; Paleomagnetic evidence; Subduction zones; Plates (structural components); dike; Eocene; exhumation; folding; foreland basin; obduction; oblique fault; paleomagnetism; subduction; transtension; New Caledonia [Melanesia]
语种	英语
来源期刊	Tectonophysics
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/207963
作者单位	Université de la Nouvelle-Calédonie, Institut des Sciences Exactes et Appliquées (EA 7484), Avenue James Cook, Nouméa, 98850, New Caledonia; Université d'Orléans, CNRS, BRGM, ISTO, UMR 7327, Orléans, F-45071, France
推荐引用方式 GB/T 7714	Dominique C.,Marion I.,Yan C.. Eocene pre- and syn-obduction tectonics in New Caledonia (Southwest Pacific), a case for oblique subduction, transcurrent tectonics and oroclinal bending; structural and paleomagnetic evidence[J],2021,811.
APA	Dominique C.,Marion I.,&Yan C..(2021).Eocene pre- and syn-obduction tectonics in New Caledonia (Southwest Pacific), a case for oblique subduction, transcurrent tectonics and oroclinal bending; structural and paleomagnetic evidence.Tectonophysics,811.
MLA	Dominique C.,et al."Eocene pre- and syn-obduction tectonics in New Caledonia (Southwest Pacific), a case for oblique subduction, transcurrent tectonics and oroclinal bending; structural and paleomagnetic evidence".Tectonophysics 811(2021).