Isotopic constraints for identification and correlation of the pre-Alpine Carpathian-Balkan
terranes-Zircon U/Pb, Lu/Hf, and whole rock Sm/Nd methods


PN II - Program Idei

Project PN-II-ID-PCE-2011-3-0100

Contract 97/05.11.2011

Project manager: Prof. dr. Ioan Coriolan BALINTONI

Department of Geology/Babes-Bolyai University Cluj Napoca

 

 

       

Objectives:

1. Pre-Alpine terranes identification;

2. Pre-Alpine terranes provenance;

3. Pre-Alpine terranes correlation;

4. Specification of Cadomian Caledonian and Variscan thermotectonic events;

5. Docking times to Baltica or Moesia.

 

 

During the late Neoproterozoic, subduction and associated orogenic processes were common at the periphery of Gondwana and the main orogen formed along its Northern margin is known as the Avalonian-Cadomian tectonostratigraphic belt (Murphy and Nance, 1989, 1991; Murphy et al., 2006, 2010). Starting with the latest Neoproterozoic time and continuing throughout the Paleozoic, the Gondwana margin, including the Avalonian-Cadomian orogen, dismembered and the resulted fragments were incorporated into the Caledonian and Variscan belts of North and Central Americas and Europe (e.g. Neubauer, 2002; Stampfli and Kozur, 2006; Nance et al., 2010). To decipher the intricate history of these crustal fragments in terms of their origin and migration time and paths, magmatic and detrital zircons U/Pb geochronology, as well as Sm/Nd isotopic signatures have been widely utilized. Accordingly, different types of peri-Gondwanan terranes were distinguished. The Cadomian terranes were associated with the West African part of Gondwana during Neoproterozoic and early Paleozoic and developed upon older basement than the Avalonian terranes. The latter developed on relatively newly formed crust in the vicinity of the Amazonian craton (e.g. Nance and Murphy, 1994, 1996; Finger et al., 2000; Murphy and Nance, 2002; Linnemann et al., 2004, 2007). Isotopic data for Eastern Mediterranean terranes are different from both the Avalonian and Cadomian signatures, as they show affinities to the Arabian-Nubian Shield. For this reason Zulauf et al. (2007) coined the term Minoan terranes for the terranes with these particular isotopic signatures. Such terranes were also identified in Romanian Carpathians by Balintoni et al. (2009). The project theme was chosen to address the following questions in the Southeastern Europe: a) How many pre-Alpine terranes are present in the Carpathians and Balkans basements? b) What is their provenance? c) What is the docking timing to Baltica, Moesia or Laurussia? d) How were the Cadomian, Caledonian and Variscan thermotectonic events recorded in the terranes' geological history? e) Is there any correlation that can be made between the pre-Alpine terranes along the Alpine Carpathian-Balkan orogen? f) Are there any identifiable remnants of the Tornquist, Rheic, and Paleothetys oceans in this region? Except for the Northern Greece and to some extent Romanian Carpathians, all the answers to the above questions will represent geological novelties.

 
       

Research team

Prof. Dr. Ioan Coriolan Balintoni - project manager

Asist Dr. Constantin Balica - senior researcher

Prof. Dr. Vlad Codrea - senior researcher

PhD stud. Cosmin Stremtan - young researcher

 

Major achievements of the project:

Scientific achievements

Provenance of the Carpathian basement

a- East Carpathians

Bretila, Tulghes, Negrisoara and Rebra terranes had been specified;

East-African Gondwanan provenance is infered for these terranes;

since these terrane proved not to be of Cadomian affinity, a new class of terranes - Carpathian terranes - has been defined. These had been generated during an Ordovician orogenic event that affected North Africa;

b- South Carpathians

Avalonian extra Cadomian provenance of the Dragsan terrane;

Ganderian peri-Amazonian provenance of the Lainici-Paius terrane;

presence of Cadomian (post 800 Ma - i.e. 580-500 Ma) events in the Dragsan terrane; composite nature of the Dragsan terrane;

c- North Dobrogea

Avalonian provenance for Boclugea and Orliga terranes and Cadomian provenance for Megina terrane;

The Variscan Orogeny in North Dobrogea has a special and complex development since towo age groups are revealed. One group, formed by Agighiol granite, gave ages around 310 Ma, while the second group, more consistent, represented by Greci, Pricopan, Vacareni and Coslugea plutons as well as Iacobdeal alcaline granite and Iglicioara Rhyolites were emplaced around 250 Ma.

d- Moesia

New data reveal an old Amazonian craton attached with Central and North Dobrogea components during the Late Neoproterozoic and Early Paleozoic. Its basement (i.e. Ovidiu Group, intercepted by Palazu drill)has been proven as the first Archaean (2.7 Ga)component from the Romanian basement.

e- Moldavian Platform

Two orthogneisses colected from drill cores (i.e. Todireni and Batranesti drills) gave zircons of 2.07 Ga, suggesting a Paleoproterozoic age of Western margin of Sarmatia craton, as component of the larger East European Craton

Southward corelatives of the Carpathian basement

a- Rhodope orogen

Generated during Alpine orogeny;

Made of a Jurassic upper unit and a Variscan lower unit;

Our data entirely cover this orogen and confirm these assuptions.

b- SW Bulgaria

Cadomian age for Frolosh Unit;

Ordovician-lower Silurian age for Ograzhden super-unit.

c- Stara Planina

Berkovica mega-unit is made of east-Cadomian entities.

d- Zaglavak ophiolites

these Tisovita-Iuti correspondents stand up as a Variscan (i.e. 390-380 Ma) rather than a Cadomian suture

Main pre-Alpine orogenetic events that generated and/or deformed the Carpathian basement

Cadomian Orogeny

Caledonian Orogeny – Carpathian phase

Variscan Orogeny

 

Detailed descriptions of these results are given in the scientific reports (2011) (2012) (2013) (2014) (2015) and 2016

 

Methodologic achievements

Sampling of the North Dobrogea metamorphic basements

Nord-Dobrogea Orogen- majority of granitic, metagranitic and ortogneisses bodies from Orliga, Megina and Boclugea metamorphic terranes

Aditionally, an important number of quartzites and paragneisses has been sampled for detrital zircons

Sampling of Bulgarian metamorphic basements

All important units and their granitic, metagranitic and ortogneisses components from the Rhodope, Sredno Gorjie and Serbo-Macedonean Massifs were sampled to complete the evolution model and history of the Carpathian metamorphic terranes and their correlatives. In order to complete the whole picture of the origin and geologic history based on zircon dating, of the Carpathian metamorphic basement, some new sampling key points are projected for this year both soutward the Danube river, in the Balcan Mts area (Getic and Danubian Extensions) and in the Rhodope massif

Sampling of Serbian metamorphic basements

All important units and their granitic, metagranitic and ortogneisses components from the Serbian part of the Serbo-Macedonean massif were sampled

Sample processing and preparation

All the stages required for zircon extraction (except the magnetic separation) can be carried out, started with 2012 in the Heavy Minerals Separation Lab created at the Department of Geology, Babes-Bolyai University

Zircon analysis

CL (Cathodoluminiscence) screening and imaging, and U/Pb, Pb/Pb, Sm/Nd isotopic dating – Arizona LaserChron, University of Arizona, Department of Geology, Babes-Bolyai University (CL)

 

Human resource

Senior researchers have been fully involved in all activities concerning sampling, samples processing and preparation, zircon analysis, attaining high specialization in the fields of geochronology, geochemistry and specific dating methodologies:

TIMS and ID-TIMS

Pb/Pb, U/Pb, Sm/Nd

LA-MC-ICP-MS

U/Pb

Young researchers:

PhD student Stremtan Cosmin. He finished his PhD thesis at the Department of Geosciences, South Florida University (Tampa). The thesys' subject covers the Danubian granites (geochemistry, age and petrogenesis). At the same time, he is fixed-term full time employed at the Department of Geology. Therefore he was partly involved in some of the sampling, samples processing and preparation, and dating and geochemical analyses, and payed according to five months therm. He attained very good skills in the fields of geochronology, geochemistry and LA-MC-ICP-MS dating methodologies

Publications:

Balintoni, I., Balica, C., Ducea, M., Stremtan, C., 2011. Peri-Amazonian, Avalonian-type and Ganderian-type terranes in the South Carpathians, Romania: The Danubian domain basement Gondwana Research 19, 945-957.

Balintoni, I., Balica, C., Hann, H.P., 2011. About a peri-Gondwanan - North African enlarged acceptance of the Caledonian Orogeny. Studia Universitatis Babes-Bolyai, Geologia 56, 29-32.

Balintoni, I., Balica, C., Seghedi, A., Ducea, M.N., 2011. Peri-Amazonian provenance of the Central Dobrogea terrane (Romania) attested by U/Pb detrital zircon age patterns. Geologica Carpathica 62, 299-307.

Balintoni, I., Balica, C., 2012. Avalonian, Ganderian and East Cadomian terranes in South Carpathians, Romania, and Pan-African events recorded in their basement. Mineralogy and Petrology.

Zagorchev, I., Balica, C., Balintoni, I., Kozhoukharova, E., Sabau, G., Dimitrescu, R., Negulescu, E., 2012. Isotopic data on the age of the Krupnik granite pluton and its host rocks, Kresna horst, Krupnik Mountains, SW Bulgaria. Comptes Rendues de l'Academie Bulgare de Sciences 65, 977-984.

Balintoni, I., Balica, C., 2013. Carpathian peri-Gondwanan terranes in the East Carpathians (Romania): A testimony of an Ordovician, North-African orogeny. Gondwana Research 23, 1053-1070.

Balintoni, I, Balica C., Ducea, M. N., Hann H.P., 2014, Peri-Gondwanan terranes in the Romanian Carpathians: A review of their spatial distribution, origin, provenance, and evolution. Geoscience Frontiers, 5, 3, 395-411

Zagorchev, I., Balica, C., Balintoni, 2015. Repeated Crustal Melting and Ductile Flow: Possible Major Mechanisms of Rhodope Evolution. Comptes Rendues de l'Academie Bulgare de Sciences 68, 11, 1403-1416.

Zagorchev, I., Balica, C., Kozhoukharova, E., Balintoni, I. C., Sabau, I., Negulescu, E., 2015. Cadomian and post-Cadomian tectonics west of the Rhodope Massif - The Frolosh greenstone belt and the Ograzhdenian supercomplex, Geologica Macedonica, 29, 2, 101-132

Balintoni, I, Balica C., 2016, Peri-Amazonian provenance of the Euxinic Craton components in Dobrogea and of the North Dobrogean Orogen components (Romania): A detrital zircon study. Precambrian Research 278, 34-51

 

International scientific meetings and congressess

2012, Miskolc

Campeanu, M. Balica, C., Stremtan, C., Balintoni, I., 2012. AGE OF POST - COLLISIONAL EVENTS I N THE DANUBIAN DOMAI N (SOUTH CARPATHIANS, ROMANIA ): MOTRU DYKE SWARM. Acta Mineralogica - Petrographica, Abstract Series, Szeged, Vol. 7, 2012

 

2012, AGU Fall Meeting, San Francisco

Balica, C., Balintoni, I., 2012. PERI-GONDWANAN CARPATHIAN TERRANES (ROMANIA): HOW MANY PALEOZOIC OCEANS IN BETWEEN? Abstract T23B-2677. Presented at 2012 Fall Meeting, AGU, San Francisco, Calif., 3-7 Dec.

Stremtan, C., Campeanu, M., Balica, C., Ryan G. J., Savov, I. P., Balintoni, I., 2012, Post-collisional magmatism associated with Variscan orogeny in the Danubian Domain (Romanian Southern Carpathians): the Motru Dyke Swarm. Abstract V11D-2791,Presented at 2012 Fall Meeting, AGU, San Francisco, Calif., 3-7 Dec

 

2013, EGU General Assembly, May 02-07 2010 Vienna

Balica, C., Balintoni, I., Seghedi, A., 2013. Gondwanan, peri-Amazonian terranes in North Dobrogea, Romania: Megina metamorphic sequence. Geophysical Research Abstracts, Vol. 15, EGU2013-11731-1, 2013.

Campeanu, M. Balica, C., Balintoni, I., Stremtan, C., 2013. Late Variscan postcollisional extensional events in the Danubian domain (Romania): the Motru Dyke System. Geophysical Research Abstracts, Vol. 15, EGU2013-12451-1, 2013.

Stremtan, C., Balica, C., Savov, I. P., Ryan G. J., Balintoni, I., 2013. The role of the mantle in Variscan post-collisional magmatism – insights from Muntele Mic and Culmea Cernei plutons (Romanian Southern Carpathians). Geophysical Research Abstracts, Vol. 15, EGU2013-10002, 2013.

 

2014, XX Congress of the Carpathian-Balkan Geological Association CBGA-2014, September 24-26 2014 Tirana, Albania

Balica, C., Balintoni, I., Berza, T., 2014. On the age of the Carpathian-Balkan pre-Alpine ophiolites. In: Beqiraj, A., Ionescu, C., Christofides, G, Uta, A., Beqiraj, G. E., Marku, S. (eds): Proceedings XX Congress of tha Carpathian-Balkan Geological Association, Special Issue, 1, 196-197.

Campeanu, M., Balica, C., Balintoni, I., 2014. Geochronology and emplacement conditions of the Motru Dyke System (South Carpathians, Romania). In: Beqiraj, A., Ionescu, C., Christofides, G, Uta, A., Beqiraj, G. E., Marku, S. (eds): Proceedings XX Congress of tha Carpathian-Balkan Geological Association, Special Issue, 1, 198-199.

Zagorchev, I. S., Balica, C., Bayanova, T. B., Kozhoukarova, E. S., Balintoni, I., Mitrofanov, T. P., Lyalina, B. V., Sabau, G, Negulescu, E., 2014. Precambrian metabasic relics in the Ograzhdenian supercomplex, Gorna Ribnitsa Village, Serbo-MAcedonian Massif, Southwest Bulgaria. In: Beqiraj, A., Ionescu, C., Christofides, G, Uta, A., Beqiraj, G. E., Marku, S. (eds): Proceedings XX Congress of tha Carpathian-Balkan Geological Association, Special Issue, 1, 224-227.

2015, Goldscmidt-2015, August 16-21 2015 Prague, Czech Republic

Campeanu, M., Balica, C., Balintoni, I., Tanaselia, C., 2015. Motru Dyke Swarm (South Carpathians, Romania): Emplacement age and geotectonic setting. Goldschmidt Abstracts, 2015, 459.

2016, AAPG-Europe Region Conference, 19-20 May, Bucharest, Romania

Balintoni, I., Balica, C., 2016. The Variscan history of the North Dobrogea Orogen. AAPG Europe Region Conference: Petroleum Systems of Alpine-Mediterranean Fold Belts and Basins – Abstract Book, 19-20 May 2016, Bucharest, Romania, p93.

2016, 8-th CAAWG, 1-7 Oct, Sibiu, Romania

Campeanu, M., Balica, C., Balintoni, I., Tanaselia, C., Cadar, O., 2016. REE Investigation of Motru Dyke Swarm components (South Carpathians, Romania). 8-th Confernce of the African Association of Women in Geosciences (CAAWG8), Sibiu, 1-7 Oct, 2016. Abstracts Volume, 38-39.