Blar i forfatter "Konopásek, Jiří"
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Anticlockwise metamorphic pressure–temperature paths and nappe stacking in the Reisa Nappe Complex in the Scandinavian Caledonides, northern Norway: evidence for weakening of lower continental crust before and during continental collision
Faber, Carly; Stunitz, Holger; Gasser, Deta; Jeřábek, Petr; Kraus, Katrin; Corfu, Fernando; Ravna, Erling Krogh; Konopásek, Jiří (Journal article; Tidsskriftartikkel; Peer reviewed, 2019)This study investigates the tectonostratigraphy and metamorphic and tectonic evolution of the Caledonian Reisa Nappe Complex (RNC; from bottom to top: Vaddas, Kåfjord, and Nordmannvik nappes) in northern Troms, Norway. Structural data, phase equilibrium modelling, and U-Pb zircon and titanite geochronology are used to constrain the timing and pressure–temperature (<i>P–T</i>) conditions of deformation ... -
Arc-like magmatism in syn- to post-collisional setting: The Ediacaran Angra Fria Magmatic Complex (NW Namibia) and its cross-Atlantic correlatives in the south Brazilian Florianópolis Batholith
Janousek, Vojtěch; Florisbal, Luana Moreira; Konopásek, Jiří; Jeřábek, Petr; Bitencourt, Maria de Fatima; Gadas, Petr; Erban, Vojtěch; Kopačková-Strnadová, Veronika (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-27)Ediacaran syn-tectonic plutonic rocks (amphibole gabbros, quartz diorites/tonalites to biotite- and muscovite-bearing granites) of the Angra Fria Magmatic Complex (Kaoko Belt, north-western Namibia) belong to two compositionally similar, magnesian, transitional tholeiitic–calc-alkaline suites, the Older (∼625–620 Ma) and the Younger (∼585–575 Ma). Both have counterparts in the broadly contemporaneous ... -
Autochthonous origin of the Encruzilhada Block, Dom Feliciano Belt, southern Brazil, based on aerogeophysics, image analysis and PT-paths
De Toni, Giuseppe Betino; Bitencourt, Maria de Fatima; Konopásek, Jiří; Battisti, Matheus Ariel; da Costa, Elisa Oliveira; Savian, Jairo Francisco (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-02-04)The Encruzilhada Block lies between the eastern hinterland and western foreland of the Dom Feliciano Belt (southern Brazil) and its tectonic meaning in the orogenic evolution of the belt is still poorly understood. Its low magnetic signal is similar to that of the foreland supracrustal sequences, whereas the high gammaspectrometric signal appears due to the hinterland post-collisional granitoids. ... -
Chronology of the Saxothuringian subduction in the West Sudetes (Bohemian Massif, Czech Republic and Poland)
Konopásek, Jiří; Anczkiewicz, Robert; Jerabek, Petr; Corfu, Fernando; Žáčková, Eliška (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-11-22)Isotopic dating of monazite and garnet from high-pressure metamorphic rocks exposed in the northern part of the Saxothuringian palaeo-suture in the Bohemian Massif revealed a diachronous metamorphism of various rock types that are now closely associated within allochthonous units representing the Devonian–Carboniferous subduction–accretionary complex. Mafic blueschists of the middle unit yielded ... -
Comment to “Neoproterozoic magmatic arc systems of the central Ribeira belt, SE-Brazil, in the context of the West-Gondwana pre-collisional history: A review”
Fossen, Haakon; Meira, Vinicius T.; Cavalcante, Carolina; Konopásek, Jiří; Janoušek, Vojtěch (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-25) -
A critical discussion of the subduction-collision model for the Neoproterozoic Araçuaí-West Congo orogen
Fossen, Haakon; Cavalcante, Carolina; Konopásek, Jiří; Meira, Vinicius T.; Paes de Almeida, Renato; Hollanda, Maria Helena BM de; Trompette, Roland (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-03-22)The Neoproterozoic Araçuaí-West Congo orogen in Brazil and Congo represents a branch of the Brasiliano/Pan-African orogenic system that is considered to terminate northward into a confined cratonic environment defined by the horseshoe-shaped pre-Atlantic São Francisco-Congo craton. The prevailing interpretation is that this orogen formed as a result of 50 m.y. of subduction leading to a classical ... -
Garnet growth and mineral geochronology constrains the diachronous Neoproterozoic convergent evolution of the southern Dom Feliciano Belt, Uruguay
Percival, Jack James; Konopásek, Jiří; Oyhantçabal, Pedro; Slama, Jiri; Anczkiewicz, Robert (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-05-15)The Dom Feliciano Belt of southern Brazil and Uruguay represents part of a larger Neoproterozoic orogenic system formed during the amalgamation of Western Gondwana. The hinterland and foreland domains in parts of the belt preserve deformation structures and metamorphic assemblages that developed during early crustal thickening from c. 650 Ma. However, the metamorphic history of the southern foreland, ... -
Influence of a rigid backstop on the flow pattern during thrusting of the supracrustal Balsfjord Series of the North Norwegian Caledonides
Höpfl, Stephan Maximilian; Konopásek, Jiří; Sláma, Jiří (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-17)The Caledonian evolution of the low–medium grade Balsfjord Series (Troms, Northern Norway) is characterized by four sets of deformation structures that developed progressively during burial and exhumation from underneath the high-grade Nakkedal and Tromsø nappe complexes. The Balsfjord Series commonly displays top-to-the SSE–SE directed movement during the development of the main metamorphic fabric ... -
Late Paleoproterozoic and Mesoproterozoic magmatism of the Nico Pérez Terrane (Uruguay): Tightening up correlations in southwestern Gondwana
Oriolo, Sebastián; Oyhantcabal, Pedro; Konopásek, Jiří; Basei, Miguel A.S.; Frei, Robert; Sláma, Jiří; Wemmer, Klaus; Siegesmund, Siegfried (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-04-04)New geochronological, isotopic and geochemical data were obtained from the late Paleoproterozoic and Mesoproterozoic magmatic units of the Nico Pérez Terrane (Uruguay). A U-Pb LA-ICP-MS zircon age of 1768 ± 11 Ma confirms the Statherian age for the Illescas rapakivi intrusion, being thus comparable with the age of the Campanero Unit felsic orthogneisses. Though both the Illescas and Campanero ... -
Long-lasting Cadomian magmatic activity along an active northern Gondwana margin: U–Pb zircon and Sr–Nd isotopic evidence from the Brunovistulian Domain, eastern Bohemian Massif
Soejono, Igor; Janousek, Vojtěch; Žáčková, Eliška; Sláma, Jiří; Konopásek, Jiří; Machek, Matěj; Hanžl, Pavel (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-11-03)Cadomian magmatic complexes of the Brunovistulian Domain crop out at the eastern termination of the Bohemian Massif. However, the age, nature and geotectonic affinity of some of pre-Variscan (meta-)igneous rock complexes from this domain are still unknown. Geochronological and geochemical study of the granitic rocks across the Brunovistulian Domain reveals new information about the timing and nature ... -
The onset of flysch sedimentation in the Kaoko Belt (NW Namibia) – Implications for the pre-collisional evolution of the Kaoko–Dom Feliciano–Gariep orogen
Konopásek, Jiří; Hoffmann, Karl Heinz; Sláma, Jiří; Košler, Jan (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-06-17)<p>Detrital zircon provenance study of a metamorphosed sedimentary succession in the eastern part of the Kaoko Belt in Namibia has revealed two distinct sources for the Neoproterozoic sedimentation along the southwestern Congo Craton margin. The lower part of the succession shows detrital zircon ages consistent with erosion of Paleoproterozoic basement of the Congo Craton with an inferred Mesoproterozoic ... -
P-T-D evolution of the southeast Passo Feio Complex and the meaning of the Caçapava Lineament, Dom Feliciano Belt, southernmost Brazil
da Costa, Elisa Oliveira; Bitencourt, Maria de Fatima; Tennholm, Tonje; Konopásek, Jiří; Moita, Thayse de Franceschi (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-08-05)Metamorphic–deformation paths and interpretations of regional structures are essential for the understanding of how orogens evolve. While in active orogens, structures can be easily mapped for hundreds of kilometres, regional structures in ancient mountain belts may appear only as subsurface geophysical data. In this paper, we constrain the metamorphic–deformation history of the southeastern part ... -
Pre-collisional crustal evolution of the European Variscan periphery: Constraints from detrital zircon U–Pb ages and Hf isotopic record in the Precambrian metasedimentary basement of the Brunovistulian Domain
Soejono, Igor; Schulmann, Karel; Slama, Jiří; Hrdličková, Kristýna; Hanžl, Pavel; Konopásek, Jiří; Collett, Stephen; Mikova, Jitka (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-02-23)In this study, U–Pb ages and Hf isotopic composition of detrital zircons from the Precambrian metasedimentary autochthon of the Brunovistulian Domain in the eastern Bohemian Massif were investigated to understand the pre-collisional evolution of the eastern periphery of the European Variscan belt. Detrital zircons of the Tonian sequences have mostly Paleoproterozoic to Neoproterozoic ages (c. 2.1–0.9 ... -
Pre-orogenic connection of the foreland domains of the Kaoko–Dom Feliciano–Gariep orogenic system
Percival, Jack James; Konopásek, Jiří; Eiesland, Ragnhild; Sláma, Jiří; Campos, Roberto Sacks de; Battisti, Matheus Ariel; Bitencourt, Maria de Fatima (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-30)Neoproterozoic metasedimentary rocks in the foreland domains of the Kaoko–Dom Feliciano–Gariep orogenic system record sedimentation from the breakup of Rodinia to the amalgamation of Gondwana, and thus provide ideal subjects for investigation of the mutual pre-orogenic positions of rifted margins of the African and South American cratonic blocks. U–Pb isotopic dating of zircon in the Brusque Complex ... -
Reconstruction of a volcano-sedimentary environment shared by the Porongos and Várzea do Capivarita complexes at 790 Ma, Dom Feliciano Belt, southern Brazil
Battisti, Matheus Ariel; Bitencourt, Maria de Fatima; Schmitt, Renata da Silva; Nardi, Lauro Valentim Stoll; Martil, Mariana Maturano Dias; De Toni, Giuseppe Betino; Pimentel, Márcio Martins; Armstrong, Richard; Konopásek, Jiří (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-06-22)This work investigates the pre-collisional (before ca. 650 Ma) history of the Dom Feliciano Belt in southernmost Brazil through geochronological and zircon oxygen isotope study. U–Pb SHRIMP dating of two orthogneiss samples from the Várzea do Capivarita Complex and one metarhyolite sample from the Porongos Complex yielded crystallisation ages of 786 ± 5 Ma, 780 ± 10 Ma and 787 ± 5 Ma, respectively. ... -
Tectono-Metamorphic Evolution of the Northern Dom Feliciano Belt Foreland, Santa Catarina, Brazil: Implications for Models of Subduction-Driven Orogenesis
Percival, Jack James; Konopásek, Jiří; Anczkiewicz, Robert; Ganerød, Morgan; Slama, Jiri; Campos, Roberto Sacks de; Bitencourt, Maria de Fatima (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-27)The Dom Feliciano Belt in southern Brazil and Uruguay represents the western half of a Neoproterozoic orogenic belt located in the southern portion of the South Atlantic Neoproterozoic Orogenic System. Current interpretations are divided as to the nature of orogenesis in this belt, in part owing to lacking geochronological constraints. Metamorphosed and deformed supracrustal sequences of the Brusque ... -
Transformation weakening: Diffusion creep in eclogites as a result of interaction of mineral reactions and deformation
Stunitz, Holger; Neufeld, Kai; Heilbronner, Renée; Finstad, Ane Kongsro; Konopásek, Jiří; Mackenzie, James R. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-07-09)The deformation of eclogites and the driving forces for their fabric development are an important topic, potentially allowing to determine deformation rates and stresses in subduction zones, where the greatest number of large earthquakes occurs. Here, fabric studies of grain size and shape, texture, and chemical composition from two locations of Variscan and Alpine eclogites are presented. All samples ... -
Transpressive strain partitioning between the Major Gercino Shear Zone and the Tijucas Fold Belt, Dom Feliciano Belt, Santa Catarina, southern Brazil
De Toni, Giuseppe Betino; Bitencourt, Maria de Fatima; Konopásek, Jiří; Martini, Amos; Andrade, Pedro; Florisbal, Luana Moreira; Campos, Roberto Sacks de (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-04-15)A composite cross section from the Florianópolis Batholith towards the Tijucas Fold Belt in the northern Dom Feliciano Belt (southern Brazil) is divided in three structural domains: the Major Gercino Shear Zone, the suprastructural Brusque Complex and the infrastructural Camboriú Complex. A kinematic correlation among the structural domains is based on structural and petrological data integrated ...