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001-es BibID:	BIBFORM083342
Első szerző:	Palcsu László (fizikus)
Cím:	Local temperature calibration of carbonate-water oxygen isotope fractionation and clumped isotopes (?47) in a karstic freshwater limestone environment / László Palcsu, Marianna Túri, István Futó, János Kovács, Péter Szabó, Judit Orsovszki, Marjan Temovski, László Rinyu
Dátum:	2019
ISSN:	1029-7006 1607-7962
Megjegyzések:	Oxygen isotope ratios of carbonates are widely used as palaeoclimate indicators since isotope fractionation between the carbonate and the water phase is temperature dependent. The available empirical equationsare reliable for deposits which are precipitated under isotopic equilibrium. However, in many cases, precipitation of abiotic carbonate sediments (flowstones, freshwater limestones, travertines, tufas, etc.) can occur with fast CO2 degassing, which tends to result in a kinetic fractionation of isotope compositions. In karst environments, freshwater limestone is precipitated from cold spring waters as the creek is flowing and the dissolved CO2 is released from the water. This process creates tufa deposits. Our aim is to investigate the suitability of the tufa deposits as a palaeoclimate archive, even if kinetic fractionation plays a significant role during carbonate formation. In Mecsek Mts, Hungary, tufa deposits can be found in karst valleys. We have chosen a karst spring of constant annual temperature of 10.3 ?C. As the water is flowing away from the spring, it is heated up or cooled down by the ambient air, so the annual temperature variation is increasing with the distance from the spring. In 2015, glass plates, as well as temperature loggers, were placed in the water downstream from the spring along with a 200 m long section, so that carbonate could be precipitated onto the glass surface. In 3-4 weeks the glass plates are replaced. Daily average temperatures of the water vary between 0 and 25.6 ?C, while temperatures averaged to the sampling periods vary between 0.8 and 20.1 ?C. The first ? 18Ocarb and clumped isotope results show a significant temperature dependence, although the equations are shifted from those that are reliable to equilibrium circumstances. However, both ? 18Ocarb-T and ?47-T relationships seem to be significant and therefore applicable to the old tufa layers for reconstructing palaeotemperatures.
Tárgyszavak:	Természettudományok Környezettudományok idézhető absztrakt folyóiratcikk
Megjelenés:	Geophysical Research Abstracts. - 21 (2019), p. 8493. -
További szerzők:	Túri Marianna (1988-) (geográfus-geoinformatikus) Futó István (fizikus) Kovács János Szabó Péter Orsovszki Judit Temovski, Marjan Rinyu László (fizikus)
Pályázati támogatás:	GINOP-2.3.2-15-2016-00009 GINOP
Internet cím:	Szerző által megadott URL Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM074801
035-os BibID:	(Cikkazonosító)12813 (WOS)000442608400001 (Scopus)85052329220
Első szerző:	Palcsu László (fizikus)
Cím:	Modulation of Cosmogenic Tritium in Meteoric Precipitation by the 11-year Cycle of Solar Magnetic Field Activity / László Palcsu, Uwe Morgenstern, Jürgen Sültenfuss, Gabriella Koltai, Elemér László, Marjan Temovski, Zoltán Major, Judit T. Nagy, László Papp, Carmen Varlam, Ionut Faurescu, Marianna Túri, László Rinyu, György Czuppon, Emese Bottyán, A. J. Timothy Jull
Dátum:	2018
ISSN:	2045-2322
Megjegyzések:	The relationship between the atmospheric concentration of cosmogenic isotopes, the change of solar activity and hence secondary neutron flux has already been proven. The temporal atmospheric variation of the most studied cosmogenic isotopes shows a significant anti-correlation with solar cycles. However, since artificial tritium input to the atmosphere due to nuclear-weapon tests masked the expected variations of tritium production rate by three orders of magnitude, the natural variation of tritium in meteoric precipitation has not previously been detected. For the first time, we provide clear evidence of the positive correlation between the tritium concentration of meteoric precipitation andneutron flux modulated by solar magnetic activity. We found trends in tritium time series for numerouslocations worldwide which are similar to the variation of secondary neutron flux and sun spot numbers.This variability appears to have similar periodicities to that of solar cycle. Frequency analysis, crosscorrelation analysis, continuous and cross wavelet analysis provide mathematical evidence that thecorrelation between solar cycle and meteoric tritium does exist. Our results demonstrate that theresponse of tritium variation in precipitation to the solar cycle can be used to help us understand its rolein the water cycle.
Tárgyszavak:	Természettudományok Földtudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk tritium, solar cycle
Megjelenés:	Scientific Reports. - 8 : 1 (2018), p. 1-9. -
További szerzők:	Morgenstern, Uwe Sültenfuss, Jürgen Koltai Gabriella László Elemér (1987-) (meteorológus előrejelző szakiránnyal) Temovski, Marjan Major Zoltán Nagy Judit, T. (1976-) (matematika tanár, közgazdász) Papp László Varlam, Carmen Faurescu, Ionut Túri Marianna (1988-) (geográfus-geoinformatikus) Rinyu László (fizikus) Czuppon György Bottyán Emese Jull, A. J. Timothy (1951-) (radiocarbon scientist)
Pályázati támogatás:	GINOP-2.3.2.-15-2016-00009 'ICER' GINOP
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM103310
035-os BibID:	(WOS)000805561200044 (Scopus)85131125056 (cikkazonosító)9202
Első szerző:	Temovski, Marjan
Cím:	Combined use of conventional and clumped carbonate stable isotopes to identify hydrothermal isotopic alteration in cave walls / Marjan Temovski, László Rinyu, István Futó, Kata Molnár, Marianna Túri, Attila Demény, Bojan Otoničar, Yuri Dublyansky, Philippe Audra, Victor Polyak, Yemane Asmerom, László Palcsu
Dátum:	2022
ISSN:	2045-2322
Megjegyzések:	Alteration of conventional carbonate stable isotopes (delta O-18, delta C-13) in cave walls has been shown to be a useful tool to identify cave formation driven by deep-seated processes, i.e., hypogene karstification. If combined with a prior information on the paleowater stable isotope composition, further insights can be obtained on the temperature and the source of the paleowater. Clumped isotope composition (Delta(47)) of carbonates is an independent measurement of temperature, and if combined with the conventional stable isotopes, can provide information on the paleowater stable isotope composition. On the example of Provalata Cave (N. Macedonia), we apply for the first time, both conventional and clumped stable isotope analysis, and identify two different isotope alteration trends, reflecting two distinct hydrothermal events: an older, hotter one, where isotope alteration was likely related to isotope diffusion, lowering the delta O-18 values of the carbonate; and a younger one, related to the cave formation by low-temperature CO2-rich thermal waters, with dissolution-reprecipitation as the alteration mechanism, causing decrease in delta O-18 values, and unexpected increase in delta C-13 values. The findings are further corroborated by additional insight from optical petrography and cathodoluminescence microscopy, as well as fluid inclusion analysis of secondary calcite crystals related to the cave forming phase.
Tárgyszavak:	Természettudományok Fizikai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk
Megjelenés:	Scientific Reports. - 12 : 1 (2022), p. 1-17. -
További szerzők:	Rinyu László (fizikus) Futó István (fizikus) Molnár Kata Túri Marianna (1988-) (geográfus-geoinformatikus) Demény Attila Otoničar, Bojan Dublyansky, Yuri Audra, Philippe Polyak, Victor Asmerom, Yemane Palcsu László (1975-) (fizikus)
Pályázati támogatás:	GINOP-2.3.2-15-2016-00009 GINOP
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM106949
Első szerző:	Túri Marianna (geográfus-geoinformatikus)
Cím:	ICER carbonate clumped isotope analysis of karst deposits / Marianna Túri, Andrea Czébely, Diána Kiss, Marjan Temovski, László Palcsu, László Rinyu
Dátum:	2022
Megjegyzések:	In April 2018, a 253 Plus 10 kV isotope ratio mass spectrometer equipped with a Kiel IV automatic carbonate device (Thermo Scientific) was installed at the Isotope Climatology and Environmental Research Centre (ICER), Institute for Nuclear Research, Debrecen, Hungary. Beside the analysis of the conventional carbon and oxygen isotope composition of small carbonate samples, the main application of our system is the clumped isotope thermometry of different kind of carbonate samples. The clumped carbonate measurements are carried out following the methodology of Bernasconi et al. [1]. Carbonate replicate samples (100-110 ?g) are digested by three drops of 1.95 g/cm3 phosphoric acid in the Kiel IV carbonate device. The evolved CO2 is passed through a micro-volume inlet system, which contains two LN2 traps and a Porapak trap in order to eliminate the possible hydrocarbon contaminants. The Easotope software is used for data evaluation of the measurements using the Brand parameters [2] and the carbon dioxide equilibrium scales [3, 4]. To demonstrate the achievable accuracy, precision and long-term stability of the measurement system at ICER, we analyzed international carbonate reference materials and proposed standards (ETH4, IAEA-C1, IAEA-C2, NBS-18, NBS-19, Merck Carbonate) and naturally formed travertine samples (known formation temperatures are in the range of 5-95?C) and compared them to formerly published data of two reputable laboratories from the clumped community [1, 5]. We also applied clumped carbonate analysis to several karst related research topics. One aspect is the suitability of tufa deposits as a paleoclimate archive, even if kinetic fractionation might play a significant role during carbonate formation. Another aspect is the application of clumped isotope thermometry to mammillary speleothems and hydrothermal carbonates as part of paleoclimate and speleogenetic studies. In the poster we will present our current achievements in the field of carbonate clumped isotope measurement, as well as some results on clumped isotope analysis of various carbonate deposits (tufa, mammillary speleothems, hydrothermal carbonates, dolomites) from different karst environments.
Tárgyszavak:	Természettudományok Földtudományok előadáskivonat könyvrészlet
Megjelenés:	Climate Change : The Karst Record IX (KR9) Programme & abstract / eds. Gina Moseley, Mojgan Soleimani, Linda Partl, et al. - p. 164. -
További szerzők:	Czébely Andrea (1983-) (biológus) Kiss Diána Temovski, Marjan Palcsu László (1975-) (fizikus) Rinyu László (fizikus)
Internet cím:	Szerző által megadott URL Intézményi repozitóriumban (DEA) tárolt változat
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