期刊
GONDWANA RESEARCH
卷 18, 期 1, 页码 60-81出版社
ELSEVIER
DOI: 10.1016/j.gr.2009.12.003
关键词
Miyashiro; Ophiolites; Tectonics; Volcanic rock series; Subduction; Major elements; Volcanic glasses
Miyashiro (1973) famously initiated a debate on the tectonic setting of ophiolite complexes by proposing that 'the Troodos ophiolitic complex was probably formed in an island arc'. This paper evaluates and updates Miyashiro's work by: (a) using the Mehegan-Robinson set of 137 fresh volcanic glass analyses to sidestep the controversy over the effect of alteration on major element classification diagrams; (b) using the volcanic glass database for Troodos analogues such as back-arc basins, slab edges, forearcs and subduction initiation terranes; (c) revising Miyashiro's classifications by including the boninitic series and subdividing the tholeiitic series into high- and medium-Fe series; and (d) extending Miyashiro's methodologies to new developments in the interpretation of major element data. We conclude that the Troodos Massif is made up of oceanic crust built from a high-Si8, moderate-Fe tholeiitic magma, overlain by boninites. Its low K8/H8 is consistent with near-trench crustal accretion and its Na8-Fe8 systematics indicate that T-P = c.1400 degrees C for the Lower Lavas, consistent with rapid slab roll-back and/or sideways influx of hot mantle. Overall, the geochemical characteristics and geological setting support models in which the Troodos Massif formed by slab roll-back following subduction initiation, probably near a slab edge. (c) 2009 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据