Peri-Gondwanan terranes in the Romanian Carpathians: A review of their spatial distribution, origin, provenance, and evolution

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• 作者：Ioan Balintoni^a ; ^{ioan.balintoni@ubbcluj.ro" class="auth_mail} ; Constantin Balica^a ; ^{constantin.balica@ubbcluj.ro" class="auth_mail} ; Mihai N. Ducea^b ; ^d ; ^{ducea@geo.arizona.edu" class="auth_mail} ; Horst-Peter Hann^c ; ^{hann@uni-tuebingen.de" class="auth_mail}
• 关键词：Romanian Carpathians pre-Alpine terranes ; U-Pb Geochronology ; Avalonian-type and Carpathian-type terranes ; Tornquist ; Rheic and Paleotethyan sutures ; Ordovician North-African orogen
• 刊名：Geoscience Frontiers
• 出版年：May, 2014
• 年：2014
• 卷：5
• 期：3
• 页码：395-411
• 全文大小：5738 K

文摘

The basement of the Romanian Carpathians is made of Neoproterozoic to early Paleozoic peri-Gondwanan terranes variably involved in the Variscan orogeny, similarly to other basement terrains of Europe. They were hardly dismembered during the Alpine orogeny and traditionally have their own names in the three Carpathian areas. The Danubian domain of the South Carpathians comprises the Dr膬g艧an and Lainici-P膬iu艧 peri-Amazonian terranes. The Dr膬g艧an terrane originated within the ocean surrounding Rodinia and docked with Rodinia at 鈭?00聽Ma. It does not contain Cadomian magmatism and consequently it is classified as an Avalonian extra-Cadomian terrane. The Lainici-P膬iu艧 terrane is a Ganderian fragment strongly modified by Cadomian subduction-related magmatism. It is attached to the Moesia platform. The Tisovi牛a terrane is an ophiolite that marks the boundary between Dr膬g艧an and Lainici-P膬iu艧 terranes.

The other basement terranes of the Romanian Carpathians originated close to the Ordovician North-African orogen, as a result of the eastern Rheic Ocean opening and closure. Except for the Sebe艧-Lotru terrane that includes a lower metamorphic unit of Cadomian age, all the other terranes (Bretila, Tulghe艧, Negri艧oara and Rebra in the East Carpathians, Some艧, Biharia and Baia de Arie艧 in the Apuseni mountains, Fagara艧, Leaota, Cara艧 and Pade艧 in the South Carpathians) represent late Cambrian-Ordovician rock assemblages. Their provenance, is probably within paleo-northeast Africa, close to the Arabian-Nubian shield.

The late Cambrian-Ordovician terranes are defined here as Carpathian-type terranes. According to their lithostratigraphy and origin, some are of continental margin magmatic arc setting, whereas others formed in rift and back-arc environment and closed to passive continental margin settings. In a paleogeographic reconstruction, the continental margin magmatic arc terranes were first that drifted out, followed by the passive continental margin terranes with the back-arc terranes in their front. They accreted to Laurussia during the Variscan orogeny. Some of them (Sebe艧-Lotru in South Carpathians and Baia de Arie艧 in Apuseni mountains) underwent eclogite-grade metamorphism. The Danubian terranes, the Bretila terrane and the Some艧 terrane were intruded by Variscan granitoids.