气候变化领域集成服务门户(CCPortal): Cretaceous intracontinental rifting at the southern Chatham Rise margin and initialisation of seafloor spreading between Zealandia and Antarctica

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DOI	10.1016/j.tecto.2019.228298
	Cretaceous intracontinental rifting at the southern Chatham Rise margin and initialisation of seafloor spreading between Zealandia and Antarctica
	Riefstahl F.; Gohl K.; Davy B.; Hoernle K.; Mortimer N.; Timm C.; Werner R.; Hochmuth K.
发表日期	2020
ISSN	00401951
卷号	776
英文摘要	Passive continental margins are commonly classified as magma-poor and magma-rich types. Related breakup processes are often associated with far-field tectonic stresses or upwelling mantle plumes. The Chatham Rise east off New Zealand records a sequence of Late Cretaceous tectonic events, which include subduction and collision of the oceanic Hikurangi Plateau to subsequent continental rifting and breakup. The mechanisms triggering the change in tectonic forces are poorly understood but address open questions regarding the formation of passive margins. We acquired wide-angle seismic reflection/refraction, multi-channel seismic and potential field data along three profiles crossing the southern Chatham Rise margin and SE Chatham Terrace to the oceanic crust in order to image and understand the crustal structure and breakup mechanisms. Variations in crustal thickness along the highly faulted Chatham Rise are most likely related to the collision with the Hikurangi Plateau. Our data indicate that the SE Chatham Terrace represents a broad continent-ocean transition zone (COTZ), which we interpret to consist of very thin continental crust affected by magmatic activity. Along the southern Chatham Rise margin, features of both, magma-poor and magma-rich rifted margins are present. We suggest that passive rifting initiated at 105–100 Ma related to slab dynamics after the Hikurangi Plateau collision. We revise the onset of seafloor spreading south of the eastern Chatham Rise to ~88 Ma from the extent of our inferred COTZ. Geographically extensive, but low-volume intraplate magmatism affected the margin at 85–79 Ma. We suggest that this magmatism and the onset of seafloor spreading are a response to upwelling mantle through a slab window after 90 Ma. After 85 Ma, spreading segments became connected leading to the final separation of Zealandia from Antarctica. We interpret the southern Chatham Rise margin as a unique hybrid margin whose tectonic history was influenced by passive continental rifting and mantle upwelling. © 2019 Elsevier B.V.
关键词	Chatham Rise Crustal structure Gondwana breakup Passive margins Seismic refraction Zealandia
英文关键词	Seismology; Tectonics; Chatham rise; Crustal structure; Gondwana breakups; Passive margins; Seismic refraction; Zealandia; Structural geology; collision; continental breakup; continental margin; Cretaceous; crustal structure; Gondwana; passive margin; rifting; seafloor spreading; seismic refraction; subduction; Antarctica; Denmark; Sjaelland
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/207863
作者单位	Alfred Wegener Institute Helmholtz-Centre for Polar and Marine Research, Am Alten Hafen 26, Bremerhaven, Germany; GNS Science, 1 Fairway Drive, Avalon, Lower Hutt, New Zealand; GEOMAR Helmholtz-Centre for Ocean Research, Wischhofstraße 1-3, Kiel, Germany; GNS Science, 764 Cumberland Street, Dunedin, New Zealand; School of Geography, Geology and the Environment, University of Leicester, University Road, Leicester, United Kingdom; Christian-Albrechts-Universität zu Kiel, Institute of Geosciences, Otto-Hahn-Platz 1, Kiel, Germany
推荐引用方式 GB/T 7714	Riefstahl F.,Gohl K.,Davy B.,et al. Cretaceous intracontinental rifting at the southern Chatham Rise margin and initialisation of seafloor spreading between Zealandia and Antarctica[J],2020,776.
APA	Riefstahl F..,Gohl K..,Davy B..,Hoernle K..,Mortimer N..,...&Hochmuth K..(2020).Cretaceous intracontinental rifting at the southern Chatham Rise margin and initialisation of seafloor spreading between Zealandia and Antarctica.Tectonophysics,776.
MLA	Riefstahl F.,et al."Cretaceous intracontinental rifting at the southern Chatham Rise margin and initialisation of seafloor spreading between Zealandia and Antarctica".Tectonophysics 776(2020).