气候变化领域集成服务门户(CCPortal): Neotethyan Subduction Ignited the Iran Arc and Backarc Differently

CCPortal

DOI	10.1029/2019JB018460
	Neotethyan Subduction Ignited the Iran Arc and Backarc Differently
	Shafaii Moghadam H.; Li Q.L.; Li X.H.; Stern R.J.; Levresse G.; Santos J.F.; Lopez Martinez M.; Ducea M.N.; Ghorbani G.; Hassannezhad A.
发表日期	2020
ISSN	21699313
卷号	125 期号:5
英文摘要	Most arcs show systematic temporal and spatial variations in magmatism with clear shifts in igneous rock compositions between those of the magmatic front (MF) and those in the backarc (BA). It is unclear if similar magmatic polarity is seen for extensional continental arcs. Herein, we use geochemical and isotopic characteristics coupled with zircon U-Pb geochronology to identify the different magmatic style of the Iran convergent margin, an extensional system that evolved over 100 Myr. Our new and compiled U-Pb ages indicate that major magmatic episodes for the NE Iran BA occurred at 110–80, 75–50, 50–35, 35–20, and 15–10 Ma. In contrast to NE Iran BA magmatic episodes, compiled data from MF display two main magmatic episodes at 95–75 and 55–5 Ma, indicating more continuous magmatism for the MF than for the BA. We show that Paleogene Iran serves as a useful example of a continental arc under extension. Our data also suggest that there is not a clear relationship between the subduction velocity of Neotethyan Ocean beneath Iran and magmatic activity in Iran. Our results imply that the isotopic compositions of Iran BA igneous rocks do not directly correspond to the changes in tectonic processes or geodynamics, but other parameters such as the composition of lithosphere and melt source(s) should be considered. In addition, changes in subduction zone dynamics and contractional versus extensional tectonic regimes influenced the composition of MF and BA magmatic rocks. These controls diminished the geochemical and isotopic variations between the magmatic front and backarc. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	Arc magmatism; continental arc; extension; flare-up; Iran; Urumieh-Dokhtar Magmatic Belt
语种	英语
来源期刊	Journal of Geophysical Research: Solid Earth
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/187858
作者单位	State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China; School of Earth Sciences, Damghan University, Damghan, Iran; CCFS and GEMOC ARC National Key Centre, Macquarie University, Sydney, NSW, Australia; Now at GEOMAR, Helmholtz-Zentrum für Ozeanforschung Kiel, Kiel, Germany; Geosciences Department University of Texas at Dallas, Richardson, TX, United States; Centre for Geoscience, Universidad Nacional Autonoma de Mexico, Mexico City, Mexico; Geobiotec. Departamento de Geociências, Universidade de Aveiro, Aveiro, Portugal; Departamento de Geología, Centro de Investigación Científica y de Educación Superior de Ensenada (CICESE), Ensenada, Mexico; University of Arizona, Tucson, AZ, United States; Faculty of Geology and Geophysics, University of Bucharest, Bucharest, Romania
推荐引用方式 GB/T 7714	Shafaii Moghadam H.,Li Q.L.,Li X.H.,et al. Neotethyan Subduction Ignited the Iran Arc and Backarc Differently[J],2020,125(5).
APA	Shafaii Moghadam H..,Li Q.L..,Li X.H..,Stern R.J..,Levresse G..,...&Hassannezhad A..(2020).Neotethyan Subduction Ignited the Iran Arc and Backarc Differently.Journal of Geophysical Research: Solid Earth,125(5).
MLA	Shafaii Moghadam H.,et al."Neotethyan Subduction Ignited the Iran Arc and Backarc Differently".Journal of Geophysical Research: Solid Earth 125.5(2020).