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001-es BibID:	BIBFORM116329
035-os BibID:	(Scopus)85175031969 (WoS)001092105000001 (cikkazonosító)83
Első szerző:	Molnár Kata
Cím:	Unravelling the pre-eruptive conditions of the rhyolitic Šumovit Greben lava dome from clinopyroxene-dominant glomeroporphyritic clots / Kata Molnár, Pierre Lahitte, Boglárka Döncző, Róbert Arató, János Szepesi, Zsolt Benkó, Sebastien Nomade, Jochen Gätjen, Stéphane Dibacto, Marjan Temovski
Dátum:	2023
ISSN:	0010-7999
Megjegyzések:	Detailed analyses of mineral composition and whole-rock geochemical data helped to unravel the volcanic plumbing system beneath the rhyolitic Sumovit Greben lava dome, the westernmost member of the Kozuf-Voras volcanic system (N. Macedonia). It is characterized by high SiO2 content (> 70 wt%) coupled with low MgO (< 1 wt%) and Sr (< 500 ppm) suggesting fractionation of clinopyroxene and plagioclase at depth forming a crystal mush and a crystal-poor rhyolitic lens by fractional crystallization and melt extraction on top of it. The crystal mush is composed of mainly clinopyroxene, biotite and plagioclase, whereas sanidine and plagioclase are the most abundant phenocrysts of the rhyolitic lens. The main dome forming event occurred at ca. 2.9 Ma, which sampled the crystal-poor rhyolitic lens. After a short quiescence time, an explosive eruption occurred depositing a massive lapilli tuff layer northwest of the lava dome, and an extrusion of a small-volume lava flow on the northern side of the lava dome at ca. 2.8 Ma. This latter sampled also the crystal mush, as it contains abundant glomeroporphyritic clots of clinopyroxene +/- plagioclase +/- biotite. The clinopyroxene phenocrysts are chemically homogeneous, their crystallization temperature is ca. 900(degrees)C representing the crystal mush, whereas the plagioclase and the sanidine crystallized at a lower temperature (ca. 790(degrees)C) representing the rhyolitic lens. Noble gas isotopic composition of the clinopyroxene indicate no mantle-derived fluids (< 0.5%) having an R/R-a of ca. 0.04 R-a. The rejuvenation of the system probably occurred due to implementation of mafic magma at depth leading to a heat transfer and partial melting of the cumulate. This led to crystallization of Ba-rich rims of the sanidine and An- and Sr-rich rims of the plagioclase. The crystal mush zone beneath Sumovit Greben might be connected to the nearby, more mafic volcanic centers, and the eruption of Sumovit Greben could have been the start of the last cycle in the lifetime of the Kozuf-Voras volcanic system.
Tárgyszavak:	Természettudományok Földtudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk Rhyolite Clinopyroxene Noble gases Volcanic plumbing system Sanidine Ar/Ar dating
Megjelenés:	Contributions To Mineralogy And Petrology. - 178 : 11 (2023), p. 1-17. -
További szerzők:	Lahitte, Pierre Döncző Boglárka (1987-) (biológiatanár-földrajztanár) Arató Róbert Szepesi János Benkó Zsolt (1980-) (geológus) Nomade, Sebastien Gätjen, Jochen Dibacto, Stéphane Temovski, Marjan
Pályázati támogatás:	GINOP-2.3.2-15-2016-00009 GINOP GINOP-2.3.3-15-2016-00029 GINOP
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM106604
035-os BibID:	(WoS)000734011500001 (Scopus)85121652725
Első szerző:	Molnár Kata
Cím:	The westernmost Late Miocene-Pliocene volcanic activity in the Vardar zone (North Macedonia) / Kata Molnár, Pierre Lahitte, Stéphane Dibacto, Zsolt Benkó, Samuele Agostini, Boglárka Döncző, Artur Ionescu, Ivica Milevski, Zita Szikszai, Zsófa Kertész, Marjan Temovski
Dátum:	2021
ISSN:	1437-3254
Megjegyzések:	Late Miocene to Pleistocene volcanism within the Vardar zone (North Macedonia) covers a large area, has a wide range in composition, and is largely connected to the tectonic evolution of the South Balkan extensional system, the northern part of the Aegean extensional regime. The onset of the scattered potassic to ultrapotassic volcanism south from the ScutariPeć transverse zone occurred at ca. 8.0 Ma based on this study. Here, we focused on three volcanic centers located on deep structures or thrust faults along the western part of the Vardar zone, for which there is none to very little geochronological and geochemical data available. Pakoševo and Debrište localities are represented as small remnants of lava fows cropping out at the southern edge of Skopje basin and at the western edge of Tikveš basin, respectively. Šumovit Greben center is considered as part of the Kožuf-Voras volcanic system, and it is located on its westernmost side, at the southern edge of Mariovo basin, which is largely composed of volcaniclastic sediments. We present new eruption ages applying the unspiked Cassignol-Gillot K-Ar technique on groundmass, as well as petrological and geochemical data, supplemented with Sr and Nd isotopes to complement and better understand the Neogene-Pleistocene volcanism in the region. Eruption ages on these rocks interlayered between sedimentary formations allow to better constrain the evolution of those sedimentary basins. Rocks from the three volcanic centers belong to the high-K calc-alkaline-shoshonitic series based on their elevated K content. The oldest center amongst these three localities, as well as other Late Miocene centers within the region, is the trachyandesitic Debrište, which formed at ca. 8.0 Ma, and exhibits the highest Nd and lowest Sr isotopic ratios (0.512441-0.512535 and 0.706759-0.706753, respectively). The basaltic trachyandesite Pakoševo center formed at ca. 3.8 Ma and its Nd and Sr isotopic ratios (0.512260 and 0.709593, respectively) bear the strongest signature of crustal contamination. The rhyolitic Šumovit Greben center is a composite volcanic structure formed at ca. 3.0-2.7 Ma. Its youngest eruption unit has a slightly higher Nd and lower Sr isotopic ratios (0.512382 and 0.709208, respectively) representing a magma with a lesser extent of crustal assimilation than the other samples from this center. The overall trend through time in the Sr and Nd isotopic ratios of the Late Miocene to Pleistocene mafc volcanic centers in the region implies an increasing rate of metasomatism of the lithospheric mantle.
Tárgyszavak:	Természettudományok Földtudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk Unspiked Cassignol-Gillot K-Ar dating Late Miocene-Pleistocene Volcanism Vardar zone Sr and Nd isotopes
Megjelenés:	International Journal Of Earth Sciences. - 111 : 3 (2021), p. 749-766. -
További szerzők:	Lahitte, Pierre Dibacto, Stéphane Benkó Zsolt (1980-) (geológus) Agostini, Samuele Döncző Boglárka (1987-) (biológiatanár-földrajztanár) Ionescu, Artur Milevski, Ivica Szikszai Zita (1969-) (fizikus) Kertész Zsófia (1971-) (fizikus) Temovski, Marjan
Pályázati támogatás:	GINOP-2.3.2-15-2016-00009 GINOP TÉT-FR-2018-00018 Egyéb
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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