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DOI	10.1016/j.earscirev.2021.103791
	On the origins of the Iapetus ocean
	Robert B.; Domeier M.; Jakob J.
发表日期	2021
ISSN	0012-8252
卷号	221
英文摘要	The Iapetus Ocean opened during the fission of the supercontinent Rodinia, from the breakup of three of its core continental constituents: Laurentia, Baltica and Amazonia. The timing of Iapetus opening is still much debated, with estimates ranging from 700 to 550 Ma. Similarly debated is exactly how Laurentia, Baltica and Amazonia were positioned relative to each other immediately before their breakup. In this study, we reconsider the timing and framework of Iapetus opening by integrating the fragmentary mid-Neoproterozoic to early Cambrian observational records from these continents. We first demonstrate that paleomagnetic data, despite being both sparse and probably contaminated by some global-scale, non-uniformitarian process in Ediacaran time, support the existence of a wide ocean between these continents by 575 Ma. However, the paleomagnetic data alone are insufficient to allow the formulation of more specific conclusions concerning the timing and paleogeography of Iapetus opening. We therefore conduct an extensive review of the mid-Neoproterozoic to Cambrian geology of eastern Laurentia, western Baltica and western Amazonia which, jointly interpreted with the paleomagnetic constraints, allow us to construct a self-consistent and geodynamically feasible plate tectonic model. In this model, the breakup of Laurentia, Baltica and Amazonia was polyphase, involving the spalling of multiple marginal terranes from Laurentia and the successive opening of several oceans, including a composite ‘Iapetus Ocean’. The first phase of continental breakup occurred between eastern Laurentia and western Amazonia at 750–700 Ma, leading to the opening of the Puncoviscana Ocean. This was followed by the opening of the eastern branch of the Iapetus Ocean, between Laurentia and Baltica, at ~590 Ma, which may have been instigated by emplacement of the Central Iapetus Magmatic Province. The western branch of Iapetus subsequently opened at ~550 Ma by the detachment of marginal terranes from eastern Laurentia, following a protracted phase of rifting. We contend that our preferred scenario is the simplest solution given the presently available evidence but throughout this review we underline key outstanding questions and the attendant uncertainties in our preferred model. © 2021 The Authors
英文关键词	Cambrian; Iapetus; Neoproterozoic; Paleomagnetism; Plate tectonics
语种	英语
来源期刊	EARTH-SCIENCE REVIEWS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/209181
作者单位	The Centre for Earth Evolution and Dynamics, University of Oslo, Oslo, Norway; GFZ German Research Centre for Geosciences, Potsdam, Germany; Geological Survey of Norway (NGU), Trondheim, Norway
推荐引用方式 GB/T 7714	Robert B.,Domeier M.,Jakob J.. On the origins of the Iapetus ocean[J],2021,221.
APA	Robert B.,Domeier M.,&Jakob J..(2021).On the origins of the Iapetus ocean.EARTH-SCIENCE REVIEWS,221.
MLA	Robert B.,et al."On the origins of the Iapetus ocean".EARTH-SCIENCE REVIEWS 221(2021).