气候变化领域集成服务门户(CCPortal): The early Paleozoic cumulate gabbroic rocks from the southwest part of the Tisza Mega-Unit (Mt. Papuk; NE Croatia): evidence of a Gondwana suture zone

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DOI	10.1007/s00531-020-01896-8
	The early Paleozoic cumulate gabbroic rocks from the southwest part of the Tisza Mega-Unit (Mt. Papuk; NE Croatia): evidence of a Gondwana suture zone
	Slovenec D.; Belak M.; Mišur I.; Šegvić B.; Schuster R.
发表日期	2020
ISSN	14373254
起始页码	2209
结束页码	2233
卷号	109 期号:6
英文摘要	The Mt. Papuk heteroadcumulate pyroxene–amphibole gabbronorites, which outcrops at the southern margin of the Tisza Mega-Unit, is suggested to stem from the deep oceanic crust formed by the in situ crystallisation in a supposed magma chamber. Amphibole oikocrystals are found to define a poikilitic texture of analysed rocks. A common enclosure in amphibole is the cumulus orthopyroxene, and rarely, the clinopyroxene and/or plagioclase and spinel. The chemical composition of related minerals and their crystallisation sequence suggest the sub-solidus crystallisation of gabbronorite in an open system at high temperatures and medium pressures. Parental magmas originated from the moderately depleted mantle source, which was metasomatised prior to melting. Early mineral fractionation gave rise to the assemblage consisted of spinel, pyroxene, plagioclase and intercumulus amphibole. The rocks’ bulk chemistry, mineral crystallisation sequence, pyroxene geochemistry and myriad of high Ca-plagioclase, which coexists with igneous Ca-amphibole are all in favour of the strong subduction influence typical for mafic intrusion formed above mantle wedge in the root of an island arc at depths of 10–21 km. Herein presented geochemical and isotopic data (40Ar–39Ar: 487.1 ± 4.3 Ma and Sm–Nd: 505 Ma) go along with the existence of an intra-oceanic arc related to geodynamic events that took place in the Prototethyan oceanic realm s.l. during middle Cambrian to earliest Ordovician. These events were likely correlated with the subduction of the Quaidam(?) back-arc ocean, or alternatively, with the subduction and closure of Prototethyan branches located between microcontinental fragments of Asia. Initially, the closure of back-arc oceans led to crust fragmentation and, then, addition of non-metamorphosed mafites into the obducted sequence further from the active continental margins of Gondwana and Laurassia at the time of the formation of Pangea in the late Palaeozoic. © 2020, Geologische Vereinigung e.V. (GV).
英文关键词	Cumulate gabbronorite; Early Paleozoic; Gondwana suture zone; Intra-oceanic island arc; Mt. Papuk; Tisza Mega-Unit
语种	英语
scopus关键词	amphibole; cumulate; gabbro; Gondwana; magma chamber; oceanic crust; outcrop; Paleozoic; pyroxene; suture zone; Croatia; Mount Papuk; Tisza Valley
来源期刊	International Journal of Earth Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/147636
作者单位	Croatian Geological Survey, Sachsova 2, Zagreb, HR-10 000, Croatia; Department of Geosciences, Texas Tech University, 1200 Memorial Circle, Lubbock, TX 79409, United States; Geologische Bundesanstalt, Neulinggasse 38, Vienna, 1030, Austria
推荐引用方式 GB/T 7714	Slovenec D.,Belak M.,Mišur I.,et al. The early Paleozoic cumulate gabbroic rocks from the southwest part of the Tisza Mega-Unit (Mt. Papuk; NE Croatia): evidence of a Gondwana suture zone[J],2020,109(6).
APA	Slovenec D.,Belak M.,Mišur I.,Šegvić B.,&Schuster R..(2020).The early Paleozoic cumulate gabbroic rocks from the southwest part of the Tisza Mega-Unit (Mt. Papuk; NE Croatia): evidence of a Gondwana suture zone.International Journal of Earth Sciences,109(6).
MLA	Slovenec D.,et al."The early Paleozoic cumulate gabbroic rocks from the southwest part of the Tisza Mega-Unit (Mt. Papuk; NE Croatia): evidence of a Gondwana suture zone".International Journal of Earth Sciences 109.6(2020).