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001-es BibID:	BIBFORM080863
Első szerző:	Karátson Dávid (földrajz-biológia tanár)
Cím:	The latest explosive eruptions of Ciomadul (Csomád) volcano, East Carpathians : A tephrostratigraphic approach for the 51-29 ka BP time interval / D. Karátson, S. Wulf, D. Veres, E. K. Magyari, R. Gertisser, A. Timar-Gabor, Á. Novothny, T. Telbisz, Z. Szalai, V. Anechitei-Deacu, O. Appelt, M. Bormann, Cs. Jánosi, K. Hubay, F. Schäbitz
Dátum:	2016
ISSN:	0377-0273
Megjegyzések:	The most recent, mainly explosive eruptions of Ciomadul, the youngest volcano in the Carpatho-Pannonian Region, have been constrained by detailed field volcanological studies, major element pumice glass geochemistry, luminescence and radiocarbon dating, and a critical evaluation of available geochronological data. These investigations were complemented by the first tephrostratigraphic studies of the lacustrine infill of Ciomadul's twin craters (St. Ana and Moho₀s) that received tephra deposition during the last eruptions of the volcano. Our analysis shows that significant explosive activity, collectively called EPPA (Early Phreatomagmatic and Plinian Activity), started at Ciomadul in or around the present-day Moho₀s, the older crater, at ?51 ka BP. These eruptions resulted in a thick succession of pyroclastic-fall deposits found in both proximal and medial/distal localities around the volcano, characterized by highly silicic (rhyolitic) glass chemical compositions (ca. 75.2?79.8 wt.% SiO2). The EPPA stage was terminated by a subplinian/plinian eruption at ?43 ka BP, producing pumiceous pyroclasticfall and -flow deposits of similar glass composition, probably from a "Proto-St. Ana" vent located at or around the younger crater hosting the present-day Lake St. Ana. After a quiescent period with a proposed lava dome growth in the St. Ana crater, a new explosive stage began, defined as MPA (Middle Plinian Activity). In particular, a significant two-phase eruption occurred at ~31.5 ka BP, producing pyroclastic flows from vulcanian explosions disrupting the preexisting lava dome of Sf. Ana, and followed by pumiceous fallout from a plinian eruption column. Related pyroclastic deposits show a characteristic, less evolved rhyolitic glass composition (ca. 70.2? 74.5 wt.% SiO2) and occur both in proximal and medial/distal localities up to 21 km from source. The MPA eruptions, that may have pre-shaped a crater similar to, but possibly smaller than, the present-day St. Ana crater, was followed by a so far unknown, but likewise violent last eruptive stage from the same vent, creating the final morphology of the crater. This stage, referred to as LSPA (Latest St. Ana Phreatomagmatic Activity), produced pyroclastic-fall deposits of more evolved rhyolitic glass composition (ca. 72.8?78.8 wt.% SiO2) compared to that of the previous MPA stage. According to radiocarbon age constraints on bulk sediment, charcoal and organic matter from lacustrine sediments recovered from both craters, the last of these phreatomagmatic eruptions ? that draped the landscape toward the east and southeast of the volcano ? occurred at ~29.6 ka BP, some 2000 years later than the previously suggested last eruption of Ciomadul.
Tárgyszavak:	Természettudományok Földtudományok idegen nyelvű folyóiratközlemény külföldi lapban Ciomadul Tephrostratigraphy Quaternary Carpathians Radiometric chronology
Megjelenés:	Journal Of Volcanology And Geothermal Research. - 319 (2016), p. 29-51. -
További szerzők:	Wulf, Sabine Veres Dániel Magyari Enikő (1973-) (biológus) Gertisser, R. Timar-Gabor A. Novothny, Á. Telbisz Tamás Szalai Zita Anechitei-Deacu, V. Appelt, O. Bormann, Marc Jánosi Csaba Hubay Katalin (1985-) (biológus, környezetkutató) Schäbitz, Frank
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001-es BibID:	BIBFORM079877
Első szerző:	Veres Dániel
Cím:	New chronological constraints for Middle Palaeolithic (MIS 6/5-3) cave sequences in Eastern Transylvania, Romania / Daniel Veres, Marian Cosac, Christoph Schmidt, George Murătoreanu, Ulrich Hambach, Katalin Hubay, Sabine Wulf, David Karátson
Dátum:	2018
ISSN:	1040-6182
Megjegyzések:	The Middle to Upper Palaeolithic transition is one of the crucial periods of change in the prehistory of Europe due to the full emergence, continent-wide, of modern human lithic technologies, and detrimental of Neanderthal survival. Knowledge about the transition is growing, however, the evidence for cultural and technological developments for the Middle Palaeolithic in the Carpathian ? Lower Danube Basin is still rather sparse. Here we discuss latest findings arising from a chronological investigation of Middle Palaeolithic assemblages within the Varghis karst, Eastern Transylvania, Romania. Combining our first chronological results with information from previous excavations, we can distinguish two main stages of habitation (albeit Middle Palaeolithic lithics and faunal remains appear scattered throughout the investigated profile) within the Abri 122 rock shelter. In order to augment the typological cultural considerations, we applied direct radiocarbon dating on bones and charcoal from within the occupation layers. Radiocarbon dating of bones suggests that the Middle Palaeolithic sequence is older than the upper dating limit of the method, whereas direct luminescence ages on the lowermost productive horizon and immediately above it indicate surprisingly old ages of ca. 106?141 ka (OSL ? optically stimulated) or 99?174 ka (IRSL ? infrared stimulated). Multiple-protocol dating of charcoal found within the two habitation layers produced ages >38 14C ka BP, also suggesting that the lowermost lithic-rich horizon pertains to the Middle Palaeolithic industries. Overall, the recovered lithics, currently forming one of the most significant collections for Romania, are fully consistent with two main habitation phases connected to Middle Palaeolithic cultural affinities. The occurrence of a volcanic ash layer within Ursului Cave and originating from the Ciomadul volcanic complex (Carpathians) is first reported here. Recently dated to ? ? 43 (?50) ka, it might represent an important marker horizon, providing that it is identified within other Palaeolithic cave assemblages.
Tárgyszavak:	Természettudományok Környezettudományok idegen nyelvű folyóiratközlemény külföldi lapban Middle palaeolithicVarghis karstAbri 122MIS 6/5-3Carpathian tephraRomania
Megjelenés:	Quaternary International. - 485 (2018), p. 103-114. -
További szerzők:	Cosac, Marian Schmidt, Christoph Murătoreanu, George Hambach, Ulrich Hubay Katalin (1985-) (biológus, környezetkutató) Wulf, Sabine Karátson Dávid (1964- ) (földrajz-biológia tanár)
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