Petrological characteristics and geochemical compositions of the Neotethyan Mersin ophiolite (southern Turkey): Processes of melt depletion, refertilization, chromitite formation and oceanic crust generation

doi:10.1016/j.jseaes.2019.01.003

CORC > 地质与地球物理研究所 > 中国科学院地质与地球物理研究所 > 中国科学院矿产资源研究重点实验室

	Petrological characteristics and geochemical compositions of the Neotethyan Mersin ophiolite (southern Turkey): Processes of melt depletion, refertilization, chromitite formation and oceanic crust generation
	Saka, Samet 1; Uysal, Ibrahim 1; Kapsiotis, Argyrios 2,9; Bagci, Utku 3; Ersoy, E. Yalcin 4; Su, Ben-Xun 5; Seitz, Hans-Michael 6; Hegner, Ernst 7,8
刊名	JOURNAL OF ASIAN EARTH SCIENCES
	2019-06-01
卷号	176 页码:281-299
关键词	Ophiolite Boninite Chromitite Subduction initiation Geochemistry Mineralogy Turkey Neotethys
ISSN号	1367-9120
DOI	10.1016/j.jseaes.2019.01.003
英文摘要	The Mersin ophiolite of the Central Taurides in southern Turkey represents an incomplete section of ocean lithosphere consisting from bottom to top of chromitite-bearing mantle peridotites, cumulate dunites, clinopyroxenites, and gabbros with rare pillow lavas covered by bathypelagic sedimentary rocks. The tectonized peridotites are harzburgites with minor dunites. They are strongly melt-depleted peridotites, comprising chromian spinel (Cr-spinel) with medium to high Cr-numbers (Cr#) [100 x Cr/(Cr + Al) = 48-82] and low Al2O3 concentrations (0.05-2.2 wt%). They display concave chondrite-normalized rare earth element (REE) patterns, which we interpret as evidence for their refertilization by boninitic melts in a mantle wedge. Geochemical evidence suggests that the parental magmas of the high-Cr podiform chromitites (Cr#(sp) = 71-83) were of boninitic composition. The chromitites host a platinum-group mineral (PGM) assemblage of laurite [Ru#-64.0-90.7] and Os-Ir alloys, indicating crystallization within a range of low fS(2) conditions (logfS(2) similar to -2 to -1.3) and a T-max of similar to 1200 degrees C. Mineral compositions and geochemical data of the basalts show tholeiitic to alkali compositions. The tholeiites show mildly light REE depleted patterns and high Th/Yb and La/Nb ratios indicate the presence of a sediment component, implying a subduction-related origin. Petrogenetic modeling indicates that the tholeiitic basalts resulted from 20% melting of a spinel-bearing asthenospheric mantle. The initial epsilon(Nd) values of 7.2 and 4.9 for two tholeiite samples indicate depleted asthenosphere and more enriched mantle sources probably due to the input of older sediment. A comparison with the data of other ophiolite complexes from southern Turkey suggests subduction-overprinted mantle sources as seen in immature island arcs. The trace element patterns of the alkali basalts are similar to OIB implying an origin unrelated to that of the ophiolite assemblage. The composition of the OIB can be modeled by mixing of magmas from low-degree (1-2%) melting of garnet-bearing lherzolite (GLS) with melt fractions from a spinel-bearing lherzolite (SLS) at variable proportions (GLS/SLS = 7/10-1/10). We propose the following tectono-magmatic model for the petrogenetic evolution of the Mersin ophiolite: i) oceanic ridge spreading generated MORE type magmas (not observed in our sample collection), (ii) melting of deep mantle sources beneath MORB type crust generated OIB-like basalts in Neo-Tethyan oceanic basin, (iii) subduction initiation and formation of an infant forearc basin formed island arc tholeiites and boninites.
资助项目	TUBITAK project[109Y219] ; National Natural Science Foundation of China[41772055]
WOS关键词	POZANTI-KARSANTI OPHIOLITE ; PLATINUM-GROUP ELEMENTS ; OIB-TYPE COMPONENTS ; PODIFORM CHROMITITES ; TRACE-ELEMENTS ; SUPRA-SUBDUCTION ; UPPER-MANTLE ; ABYSSAL PERIDOTITES ; TAURIDE OPHIOLITES ; MAGMATIC PROCESSES
WOS研究方向	Geology
语种	英语
出版者	PERGAMON-ELSEVIER SCIENCE LTD
WOS记录号	WOS:000466823600023
资助机构	TUBITAK project ; TUBITAK project ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; TUBITAK project ; TUBITAK project ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; TUBITAK project ; TUBITAK project ; National Natural Science Foundation of China ; National Natural Science Foundation of China ; TUBITAK project ; TUBITAK project ; National Natural Science Foundation of China ; National Natural Science Foundation of China
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/91501]
专题	地质与地球物理研究所_中国科学院矿产资源研究重点实验室
通讯作者	Saka, Samet
作者单位	1.Karadeniz Tech Univ, Dept Geol Engn, TR-61080 Trabzon, Turkey 2.Sun Yat Sen Univ, Sch Earth & Geol Engn, Guangzhou 510275, Guangdong, Peoples R China 3.Mersin Univ, Dept Geol Engn, TR-33343 Mersin, Turkey 4.Dokuz Eylul Univ, Dept Geol Engn, TR-35390 Izmir, Turkey 5.Chinese Acad Sci, Inst Geol & Geophys, Key Lab Mineral Resources, Beijing 100029, Peoples R China 6.Goethe Univ Frankfurt, Inst Geowissensch Petrol & Geochem, Frankfurt, Germany 7.Ludwig Maximilians Univ Munchen, Dept Earth & Environm Sci, Munich, Germany 8.Ludwig Maximilians Univ Munchen, GeoBioctr, Munich, Germany 9.Ayiou Mina 31, Salamina 18900, Greece
推荐引用方式 GB/T 7714	Saka, Samet,Uysal, Ibrahim,Kapsiotis, Argyrios,et al. Petrological characteristics and geochemical compositions of the Neotethyan Mersin ophiolite (southern Turkey): Processes of melt depletion, refertilization, chromitite formation and oceanic crust generation[J]. JOURNAL OF ASIAN EARTH SCIENCES,2019,176:281-299.
APA	Saka, Samet.,Uysal, Ibrahim.,Kapsiotis, Argyrios.,Bagci, Utku.,Ersoy, E. Yalcin.,...&Hegner, Ernst.(2019).Petrological characteristics and geochemical compositions of the Neotethyan Mersin ophiolite (southern Turkey): Processes of melt depletion, refertilization, chromitite formation and oceanic crust generation.JOURNAL OF ASIAN EARTH SCIENCES,176,281-299.
MLA	Saka, Samet,et al."Petrological characteristics and geochemical compositions of the Neotethyan Mersin ophiolite (southern Turkey): Processes of melt depletion, refertilization, chromitite formation and oceanic crust generation".JOURNAL OF ASIAN EARTH SCIENCES 176(2019):281-299.