Mihály Molnár
Biographic Data
| ID | 3645696 |
|---|---|
| NAME | Mihály Molnár |
| GIVEN NAMES | Mihály |
| FAMILY NAME | Molnár |
| SIGNATURE | MOLNÁR M |
| AFFILIATIONS | HUN-REN Institute for Nuclear Research |
| VERIFIED | No |
| TOTAL WORKS | 40 |
| TOTAL CITATIONS | 79 |
| AUTHOR COUNT | 40 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 2006 |
| LATEST PUBLICATION YEAR | 2026 |
| H-INDEX | 5 |
Radiocarbon changes in the XI century CE in annual tree rings
This paper presents new radiocarbon ( 14 C) measurements from annual tree rings of English oak ( Quercus robur L.) from Kujawy, Poland, spanning 1042–1062 CE. The results confirm an increase in Δ 14 C values between 1053 and 1055 CE, within the Oort Minimum of solar activity, consistent with literature values (Brehm et al. 2021a; Eastoe et al. 2019; Terrasi et al. 2020). The data reveal a sustained increase in Δ 14 C values between 1053 and 1055 …
A speleothem record of seasonality and moisture transport around the 8.2 ka event in Central Europe (Vacska Cave, Hungary)
A stalagmite was collected in northern Hungary from the Vacska Cave, where monitoring and ventilation-based site selection had been conducted. The stalagmite covers the 10–8 ka (relative to AD 1950) period, including the so-called 8.2 ka event, and showed preceding signs of climate change that were evaluated by petrographic observations, 14 C activities, Sr concentrations, and stable isotope compositions of calcite and inclusion-hosted water. Com…
Case Study from Máza Brickyard (SW-Hungary)
The loess–paleosol profile of Máza brickyard in SW Hungary was investigated through multivariate analyses of malacofauna and sedimentological analyses. The aim was to reconstruct the complex developmental history of both sediment and malacofauna. Three age–depth models were calculated, and the best-fit model, the OxCal P-sequence, was chosen for further analysis. The profile overlays the MIS3 and MIS2, beginning at approximately 45,000–50,000 cal…
New radiocarbon dates from the Bronze Age Tiszafüred-Majoroshalom site (Eastern Hungary)
In this paper we present new AMS radiocarbon dates from the Bronze Age cemetery of Tiszafüred-Majoroshalom excavated between 1961 and 1972. The cemetery provides crucial information on the cultural development and chronology of the Bronze Age Otomani-Füzesabony and the Tumulus cultures of Eastern Central Europe, in addition to the transition between the Middle and Late Bronze Age (approx. 1500 BC) in the Great Hungarian Plain
Scaling the 14 C-Excursion Signal in Multiple Tree-Ring Series With Dynamic Time Warping
A signal of rapid changes in 14 C production is logged in annual series of 14 C derived from tree rings, which can be associated with diverse effects of cosmic-ray fluxes, including solar burst and supernova events. These 14 C signatures may vary in time and space. The intensity and structure of the 14 C signal is multifaced, which complicates understanding of the forcing and attribution of the underlying astrophysical events. It was suggested th…
Tackling erosion-accumulation events in a moat sequence from a unique Ottoman memorial place (Szigetvár, SW Hungary) using 14C and geoarcheological data
One of the most influential rulers of the sixteenth century, Sultan Suleyman I, passed away and was buried temporarily near the fortress of Szigetvár in SW Hungary in 1566. Later, a memorial place was erected on the site in the second half of the sixteenth century. The complex was surrounded by a palisade system and a moat on its northern side. The site was fully destroyed in 1692, and the exact location vanished with time. Recent investigations …
Exposure matters
Although several studies provide a broad overview of vegetation changes in the Carpathian Basin during the Holocene, stand-scale vegetation changes are lesser known because of the rarity of suitable sampling sites. In this study we investigated the sediment of a small closed-canopy site (Nagy-forrás forest hollow, 685 m a.s.l., 0.1 ha), located in the Mátra Mountains, on the north facing slope of Kékes (1014 m a.s.l.). We carried out detailed pol…
Radiocarbon Map of a Bomb-Peak Labeled Human Eye
The 14 C/ 12 C ratio of living organisms is largely determined by the 14 C/ 12 C ratio of consumed diet as well as by the atmospheric 14 C concentration together with the body’s metabolic processes. The measured 14 C content of living matter compared to the atmospheric radiocarbon level can provide invaluable information about developmental processes. Our aim was to determine the 14 C content of ten different tissues of the human eye using the 14…
Verification of Radiocarbon Transport Predicted by Numerical Modeling in the Porous Formation of NE Hungary Considering Paleo-Hydrogeology
Verification of a groundwater flow model by radiocarbon ( 14 C) data are presented taking into consideration the paleo-hydrogeological changes. Northeastern area of the Great Hungarian Plain was a deep-lying flat area, and its central part (Nyírség) has been uplifted in the last 15,000 years. These geological events have drastically changed the hydrogeological conditions of Nyírség. The groundwater flow system is composed of the Quaternary-Plioce…
Spatial Distribution of 14 C in Tree Leaves from Bali, Indonesia
The increase of fossil-fuel-derived CO 2 in the atmosphere has led to the dilution of the atmospheric radiocarbon concentration, but due to the costly instrumentation, the continuous atmospheric 14 C/ 12 C data is incomplete in developing countries, such as in Indonesia. These data give useful information about the level of local and regional fossil emissions. In this study, 14 C AMS measurements of local vegetation and woody plant species sample…
High-resolution proxy record of the environmental response to climatic variations during transition MIS3/MIS2 and MIS2 in Central Europe
North Atlantic influences on climate conditions in East-Central Europe in the late Holocene reflected by flowstone compositions
Assessment and Development of Bone Preparation for Radiocarbon Dating at Hekal
Bone is one of the most complex sample materials used for radiocarbon ( 14 C) dating. The installation of the EnvironMICADAS AMS at HEKAL (department of ICER) in 2011 required the adoption of new sample preparation techniques for small bone samples. Since then, hundreds of procedural background and known-age bones have been processed using our modified Longin method (MLM) and dated along with unknown samples. Their results are used in this study …
Adoption and Evaluation of a sample Pretreatment Protocol for Radiocarbon Dating of Cremated Bones at Hekal
A comparative study was undertaken to adopt and evaluate a radiocarbon ( 14 C) preparation procedure for accelerator mass spectrometry (AMS) measurements of cremated bones at our laboratory, including different types of archaeological samples (cremated bone, bone, charcoal, charred grain). All 14 C analyses were performed using the EnvironMICADAS AMS instrument at the Hertelendi Laboratory of Environmental Studies (HEKAL) and the ancillary analys…
Variation of 14 C in Japanese Tree Rings Related to the Fukushima Nuclear Accident
Radiocarbon ( 14 C) analysis was performed on Japanese cedar (Cryptomeria japonica) tree rings from Koriyama, Fukushima prefecture. Our primary aim was to detect any 14 C release from the Fukushima Dai-ichi nuclear power plant accident on 11 March 2011. We also completed and assessed the 14 C level in Japanese tree rings for the period of 1990–2014 because of the lack of environmental 14 C results in the Japanese island that time. For this reason…
Fossil Carbon Load in Urban Vegetation for Debrecen, Hungary
Deciduous tree leaf and grass samples were collected in Debrecen, the second largest city in Hungary. The aim of the study was to determine the rate of fossil fuel-derived carbon in urban vegetation. At the locations sampled, C3 and C4 plants close to roads were collected in September 2017. In total, 82 tree and grass leaf samples were gathered at 36 different sampling points all over the city of Debrecen. The radiocarbon ( 14 C) results of the s…
New Radiocarbon Data from the Paleosols of the NYíRSéG blown Sand Area, Hungary
Despite many ideas about the age and processes of sand movements and paleosol formation, there are still some uncertainties in this relations in the Nyírség, eastern Hungary. The major aim of the present study was to clarify the chronology of fossil soils and blown-sand layers in the sand dunes of the Nyírség using radiocarbon ( 14 C) dating on soil and charcoal samples. Charcoal and soil samples were collected from buried paleosols from differen…
Monitoring in the Barać and Lower Cerovačka caves (Croatia) as a basis for the characterization of the climatological and hydrological processes that control speleothem formation
Age–depth relationship and accumulation rates in four sediment sequences from the Retezat Mts, South Carpathians (Romania)
More Rapid 14 C Excursions in the Tree-Ring Record
Two radiocarbon ( 14 C) excursions are caused by an increase of incoming cosmic rays on a short time scale found in the Late Holocene (AD 774–775 and AD 993–994), which are widely explained as due to extreme solar proton events (SPE). In addition, a larger event has also been reported at 5480 BC (Miyake et al. 2017a), which is attributed to a special mode of a grand solar minimum, as well as another at 660 BC (Park et al. 2017). Clearly, other ev…
Temporal Variation of Atmospheric Fossil and Modern CO 2 Excess at a Central European Rural Tower Station between 2008 and 2014
In 2008, the atmospheric CO 2 measurements at the Hegyhátsál rural tower station were extended further by 14 CO 2 air sampling from two elevations (115 and 10 m a.g.l.), in cooperation with HEKAL (ICER). Since then, a complete six-year-long (2008–2014) dataset of atmospheric CO 2 , Δ 14 C, fossil, and modern CO 2 excess (relative to Jungfraujoch) has been assembled and evaluated. Based on our results, the annual mean CO 2 mole fraction rose at bo…
Reconstruction of Soil Carbon Redistribution Processes along a Hillslope Section in a Forested Area
The vertical distribution of soil organic carbon (SOC) with depth and its horizontal pattern is influenced by the topography and relief of the surface, due to lateral redistribution of soil material along slopes. Spatial and temproral variability of these changes is frequently due to human impacts on the landscape. In our study, the results of these processes were studied in detail in a small sub-catchment in a forested hillslope section using ra…
Probabilistic 14 C Age-Depth Models Aiding the Reconstruction of Holocene Paleoenvironmental Evolution of a Marshland from Southern Hungary
This paper presents first chronological results for a Holocene marshland system from the southern part of the Danube-Tisza Interfluve. Radiocarbon ( 14 C) ages were used to build age-depth models relying of probabilistic tools. Four models have been built: a linear one using dates gained via simple calibration, a P_Sequence model, fitting a polynomial function to calibrated dates; a Gamma_Sequence considering priori given and posterior accumulati…
High-Resolution Peat Core Chronology Covering the Last 12 KYR Applying an Improved Peat Bog Sampling
This work focuses on building a high-resolution age-depth model for quantitative palaeoclimate study from the Mohos peat bog, East Carpathian mountains. The investigated core presents a continuous peat profile for the last 12 kyr. The chronology was based on 36 accelerator mass spectrometry radiocarbon (AMS 14 C) analyses of the separated Sphagnum samples from different depths of the profile. Dry Sphagnum samples for AMS dating were prepared usin…
Radiocarbon-dated peat development
The peat bog at Homoródszentpál Kerek-tó (Round Lake), situated in Homoród Hills of the Eastern Carpathians in Romania, provides a continuous record of paleoclimatic and paleoenvironmental changes from the Early Holocene. In this study, we present a 7500-year-long high-resolution record of past climatic changes and signs of human impact recorded in a peat bog via integrating sedimentological, paleoecological and geochemical proxies. The basin of …
More Rapid 14 C Excursions in the Tree-Ring Record
Two radiocarbon ( 14 C) excursions are caused by an increase of incoming cosmic rays on a short time scale found in the Late Holocene (AD 774–775 and AD 993–994), which are widely explained as due to extreme solar proton events (SPE). In addition, a larger event has also been reported at 5480 BC (Miyake et al. 2017a), which is attributed to a special mode of a grand solar minimum, as well as another at 660 BC (Park et al. 2017). Clearly, other ev…
Sealed Tube Combustion Method with MnO 2 for AMS 14 C Measurement
An effective sealed tube combustion method was designed with an MnO 2 oxidant for accelerator mass spectrometry radiocarbon (AMS 14 C) measurements. Different types of materials (oxalic acid, cellulose, sucrose, wood, collagen, graphite, and humic acid) were used to test the method. A normal borosilicate glass tube was used instead of quartz and the combustion was done at 550oC. The yield of the combustion is above 98% even in the case of the les…
Adoption and Evaluation of a sample Pretreatment Protocol for Radiocarbon Dating of Cremated Bones at Hekal
A comparative study was undertaken to adopt and evaluate a radiocarbon ( 14 C) preparation procedure for accelerator mass spectrometry (AMS) measurements of cremated bones at our laboratory, including different types of archaeological samples (cremated bone, bone, charcoal, charred grain). All 14 C analyses were performed using the EnvironMICADAS AMS instrument at the Hertelendi Laboratory of Environmental Studies (HEKAL) and the ancillary analys…
Temporal Variation of Atmospheric Fossil and Modern CO 2 Excess at a Central European Rural Tower Station between 2008 and 2014
In 2008, the atmospheric CO 2 measurements at the Hegyhátsál rural tower station were extended further by 14 CO 2 air sampling from two elevations (115 and 10 m a.g.l.), in cooperation with HEKAL (ICER). Since then, a complete six-year-long (2008–2014) dataset of atmospheric CO 2 , Δ 14 C, fossil, and modern CO 2 excess (relative to Jungfraujoch) has been assembled and evaluated. Based on our results, the annual mean CO 2 mole fraction rose at bo…
Fossil Carbon Load in Urban Vegetation for Debrecen, Hungary
Deciduous tree leaf and grass samples were collected in Debrecen, the second largest city in Hungary. The aim of the study was to determine the rate of fossil fuel-derived carbon in urban vegetation. At the locations sampled, C3 and C4 plants close to roads were collected in September 2017. In total, 82 tree and grass leaf samples were gathered at 36 different sampling points all over the city of Debrecen. The radiocarbon ( 14 C) results of the s…
Assessment and Development of Bone Preparation for Radiocarbon Dating at Hekal
Bone is one of the most complex sample materials used for radiocarbon ( 14 C) dating. The installation of the EnvironMICADAS AMS at HEKAL (department of ICER) in 2011 required the adoption of new sample preparation techniques for small bone samples. Since then, hundreds of procedural background and known-age bones have been processed using our modified Longin method (MLM) and dated along with unknown samples. Their results are used in this study …
High-Precision Biogenic Fraction Analyses of Liquid Fuels by 14 C AMS at Hekal
The biocomponent ratio in liquid fuels as well as the usage of renewable resources for fuel consumption in the transport sector needs to be increased as a result of EU directive 2003/30/EC. Based on radiocarbon ( 14 C) measurements, it should be relatively simple and fast to measure the weight percentage of the fossil and biological sources by accelerator mass spectrometry (AMS) as recommended in the ASTM D 6866-12 and EN 16640 standards. In this…
Radiocarbon Map of a Bomb-Peak Labeled Human Eye
The 14 C/ 12 C ratio of living organisms is largely determined by the 14 C/ 12 C ratio of consumed diet as well as by the atmospheric 14 C concentration together with the body’s metabolic processes. The measured 14 C content of living matter compared to the atmospheric radiocarbon level can provide invaluable information about developmental processes. Our aim was to determine the 14 C content of ten different tissues of the human eye using the 14…
Spatial Distribution of 14 C in Tree Leaves from Bali, Indonesia
The increase of fossil-fuel-derived CO 2 in the atmosphere has led to the dilution of the atmospheric radiocarbon concentration, but due to the costly instrumentation, the continuous atmospheric 14 C/ 12 C data is incomplete in developing countries, such as in Indonesia. These data give useful information about the level of local and regional fossil emissions. In this study, 14 C AMS measurements of local vegetation and woody plant species sample…
New Radiocarbon Data from the Paleosols of the NYíRSéG blown Sand Area, Hungary
Despite many ideas about the age and processes of sand movements and paleosol formation, there are still some uncertainties in this relations in the Nyírség, eastern Hungary. The major aim of the present study was to clarify the chronology of fossil soils and blown-sand layers in the sand dunes of the Nyírség using radiocarbon ( 14 C) dating on soil and charcoal samples. Charcoal and soil samples were collected from buried paleosols from differen…
EnvironMicadas
A more developed and modern technology replaced the old radiocarbon measuring methods in Hungary, based on isotope separation by accelerator mass spectrometry (AMS) and not on activity measurements. In summer 2011, the EnvironMICADAS was successfully installed in the Laboratory of HEKAL, Debrecen, Hungary. In this project, a multipurpose gas-handling system was developed for the gas ion source of EnvironMICADAS at ETH Zürich, designed for the mea…
High-resolution, well-preserved tritium record in the ice of Bortig Ice Cave, Bihor Mountains, Romania
Two 2 m long ice cores (BA and BB) were extracted from the floor ice of Borştig Ice Cave in December 2005. Below a co-existing dust horizon (~13 cm underneath the 10 December 2005 ice surface) neither core presented any sign of hiatus, so the ice deposition is considered to be continuous. Tritium concentration of 94 samples from a 1.85 m long ice section were analysed by liquid scintillation counting technique. Samples from the lower 0.33 m of th…
New Radiocarbon Dates for the Baden Culture
In 2001–2002, a settlement of the Baden culture was excavated in the vicinity of Balatonoszöd. During the rescue excavation along the M7 highway, in an area of 100,000 m 2 , 2800 pits dug into the subsoil, 320 hearths, and cultural layers rich in material were discovered. The material of the Baden culture represents phases IB–IC (Boleraz), IIA (Transitional), IIB–III (Early Classical) according to Němejcová-Pavúková's (1981, 1998) typological sys…
Scaling the 14 C-Excursion Signal in Multiple Tree-Ring Series With Dynamic Time Warping
A signal of rapid changes in 14 C production is logged in annual series of 14 C derived from tree rings, which can be associated with diverse effects of cosmic-ray fluxes, including solar burst and supernova events. These 14 C signatures may vary in time and space. The intensity and structure of the 14 C signal is multifaced, which complicates understanding of the forcing and attribution of the underlying astrophysical events. It was suggested th…
Tackling erosion-accumulation events in a moat sequence from a unique Ottoman memorial place (Szigetvár, SW Hungary) using 14C and geoarcheological data
One of the most influential rulers of the sixteenth century, Sultan Suleyman I, passed away and was buried temporarily near the fortress of Szigetvár in SW Hungary in 1566. Later, a memorial place was erected on the site in the second half of the sixteenth century. The complex was surrounded by a palisade system and a moat on its northern side. The site was fully destroyed in 1692, and the exact location vanished with time. Recent investigations …
Geoarchaeological Study of Szálka and Vajda Kurgans (Great Hungarian Plain) Based on Radiocarbon and Geophysical Analyses
Two archaeologically unexplored mounds were studied in the area of the central Great Hungarian Plain. The age of the construction of the mounds was clarified on the basis of radiocarbon ( 14 C) age determination of buried soil layers. Different, later-building phases of the mounds were detected by pedological and geo-electric analyses of the human-made layers. The age of the buried soils was corrected for the reservoir age of the recent soils fou…
One-Year-Long Continuous and Synchronous Data Set of Fossil Carbon in Atmospheric PM 2.5 and Carbon Dioxide in Debrecen, Hungary
Radiocarbon investigation of atmospheric PM 2.5 aerosol synchronized with 14 CO 2 observations began in Debrecen in the winter of 2010. The aim of the study was to determine the contemporary and fossil carbon fractions in the aerosol and to set them against the fossil CO 2 excess data referring to the same period. The mass of the collected PM 2.5 mode on prebaked quartz filters was determined gravimetrically, while its total carbon mass was calcu…
Status Report of the New AMS 14C Sample Preparation Lab of the Hertelendi Laboratory of Environmental Studies (Debrecen, Hungary)
We document chemical laboratory procedures and results on international comparison samples at the Hertelendi Laboratory of Environmental Studies, Debrecen, Hungary. We also show results using the new MICADAS system and compare these results to internationally recognized standards and blank materials. The newly developed sample preparation system in HEKAL can handle samples as 1) organic material, 2) cellulose fraction of plant, 3) bones, 4) carbo…
Radiocarbon analysis of the Sárrétudvari-Őrhalom’s Graves
Results of Radiocarbon Analysis of Upper Weichselian Loess Sequences from Hungary
Approximately 10% of Hungary is covered by dust sequences of the Quaternary period. Samples have been taken from more than 50 outcrops and boreholes during fieldwork in the past 20 yr. Some 81 bulk samples taken from 27 profiles of the Hungarian loess regions have been analyzed for radiocarbon. Based on the 14 C results, loess layers that accumulated between 33,000 and 12,000 BP were selected for further investigation. The sedimentation rates of …
Combined Techniques to Date the First Turkish Bridge Over the Tisza River, Hungary
Given the fluctuating nature of the radiocarbon calibration curve, the precision of single 14 C dates on the calendar timescale is limited. However, 14 C dating combined with dendrochronology enabled us to date timbers found in the Tisza River, Hungary, during the dry period of summer 2003. Routine preparation of wood samples gave 14 C results spread over 4 centuries. By extracting alpha-cellulose from the samples, 2 distinct and relatively narro…
New Radiocarbon Dates for the Baden Culture
In 2001–2002, a settlement of the Baden culture was excavated in the vicinity of Balatonoszöd. During the rescue excavation along the M7 highway, in an area of 100,000 m 2 , 2800 pits dug into the subsoil, 320 hearths, and cultural layers rich in material were discovered. The material of the Baden culture represents phases IB–IC (Boleraz), IIA (Transitional), IIB–III (Early Classical) according to Němejcová-Pavúková's (1981, 1998) typological sys…
High-resolution, well-preserved tritium record in the ice of Bortig Ice Cave, Bihor Mountains, Romania
Two 2 m long ice cores (BA and BB) were extracted from the floor ice of Borştig Ice Cave in December 2005. Below a co-existing dust horizon (~13 cm underneath the 10 December 2005 ice surface) neither core presented any sign of hiatus, so the ice deposition is considered to be continuous. Tritium concentration of 94 samples from a 1.85 m long ice section were analysed by liquid scintillation counting technique. Samples from the lower 0.33 m of th…
Radiocarbon-Dated Paleoenvironmental Changes on a Lake and Peat Sediment Sequence from the Central Great Hungarian Plain (Central Europe) During the Last 25,000 Years
One of Hungary's geological and environmental treasures is nestled in the heart of the Great Hungarian Plain. The catchment basin of Lake Kolon was subjected to detailed environmental historical studies starting in 2005. Undisturbed cores taken along transects of the basin were subjected to detailed sedimentological, paleoecological, and geochemical studies. To establish a reliable timeframe of the lacustrine and marshland sedimentary sequence id…
Responses of terrestrial ecosystems to Dansgaard–Oeshger cycles and Heinrich-events
EnvironMicadas
A more developed and modern technology replaced the old radiocarbon measuring methods in Hungary, based on isotope separation by accelerator mass spectrometry (AMS) and not on activity measurements. In summer 2011, the EnvironMICADAS was successfully installed in the Laboratory of HEKAL, Debrecen, Hungary. In this project, a multipurpose gas-handling system was developed for the gas ion source of EnvironMICADAS at ETH Zürich, designed for the mea…
Status Report of the New AMS 14C Sample Preparation Lab of the Hertelendi Laboratory of Environmental Studies (Debrecen, Hungary)
We document chemical laboratory procedures and results on international comparison samples at the Hertelendi Laboratory of Environmental Studies, Debrecen, Hungary. We also show results using the new MICADAS system and compare these results to internationally recognized standards and blank materials. The newly developed sample preparation system in HEKAL can handle samples as 1) organic material, 2) cellulose fraction of plant, 3) bones, 4) carbo…
One-Year-Long Continuous and Synchronous Data Set of Fossil Carbon in Atmospheric PM 2.5 and Carbon Dioxide in Debrecen, Hungary
Radiocarbon investigation of atmospheric PM 2.5 aerosol synchronized with 14 CO 2 observations began in Debrecen in the winter of 2010. The aim of the study was to determine the contemporary and fossil carbon fractions in the aerosol and to set them against the fossil CO 2 excess data referring to the same period. The mass of the collected PM 2.5 mode on prebaked quartz filters was determined gravimetrically, while its total carbon mass was calcu…
Small-scale moisture availability increase during the 8.2-ka climatic event inferred from biotic proxy records in the South Carpathians (SE Romania)
In this paper, we present high-resolution early Holocene pollen, plant macrofossil, charcoal, diatom, biogenic silica, and loss-on-ignition records from a mountain lake in the South Carpathians in order to reveal ecosystem response to the 8.2-ka climatic oscillation. We found significant changes both in terrestrial vegetation and lake diatom assemblages in the northern slope of the Retezat Mts between c. 8300 and 8000 cal. yr BP. Rapid changes in…
Recrystallization-induced oxygen isotope changes in inclusion-hosted water of speleothems – Paleoclimatological implications
Monitoring in the Barać and Lower Cerovačka caves (Croatia) as a basis for the characterization of the climatological and hydrological processes that control speleothem formation
Age–depth relationship and accumulation rates in four sediment sequences from the Retezat Mts, South Carpathians (Romania)
More Rapid 14 C Excursions in the Tree-Ring Record
Two radiocarbon ( 14 C) excursions are caused by an increase of incoming cosmic rays on a short time scale found in the Late Holocene (AD 774–775 and AD 993–994), which are widely explained as due to extreme solar proton events (SPE). In addition, a larger event has also been reported at 5480 BC (Miyake et al. 2017a), which is attributed to a special mode of a grand solar minimum, as well as another at 660 BC (Park et al. 2017). Clearly, other ev…
Temporal Variation of Atmospheric Fossil and Modern CO 2 Excess at a Central European Rural Tower Station between 2008 and 2014
In 2008, the atmospheric CO 2 measurements at the Hegyhátsál rural tower station were extended further by 14 CO 2 air sampling from two elevations (115 and 10 m a.g.l.), in cooperation with HEKAL (ICER). Since then, a complete six-year-long (2008–2014) dataset of atmospheric CO 2 , Δ 14 C, fossil, and modern CO 2 excess (relative to Jungfraujoch) has been assembled and evaluated. Based on our results, the annual mean CO 2 mole fraction rose at bo…
Reconstruction of Soil Carbon Redistribution Processes along a Hillslope Section in a Forested Area
The vertical distribution of soil organic carbon (SOC) with depth and its horizontal pattern is influenced by the topography and relief of the surface, due to lateral redistribution of soil material along slopes. Spatial and temproral variability of these changes is frequently due to human impacts on the landscape. In our study, the results of these processes were studied in detail in a small sub-catchment in a forested hillslope section using ra…
Probabilistic 14 C Age-Depth Models Aiding the Reconstruction of Holocene Paleoenvironmental Evolution of a Marshland from Southern Hungary
This paper presents first chronological results for a Holocene marshland system from the southern part of the Danube-Tisza Interfluve. Radiocarbon ( 14 C) ages were used to build age-depth models relying of probabilistic tools. Four models have been built: a linear one using dates gained via simple calibration, a P_Sequence model, fitting a polynomial function to calibrated dates; a Gamma_Sequence considering priori given and posterior accumulati…
High-Resolution Peat Core Chronology Covering the Last 12 KYR Applying an Improved Peat Bog Sampling
This work focuses on building a high-resolution age-depth model for quantitative palaeoclimate study from the Mohos peat bog, East Carpathian mountains. The investigated core presents a continuous peat profile for the last 12 kyr. The chronology was based on 36 accelerator mass spectrometry radiocarbon (AMS 14 C) analyses of the separated Sphagnum samples from different depths of the profile. Dry Sphagnum samples for AMS dating were prepared usin…
Radiocarbon-dated peat development
The peat bog at Homoródszentpál Kerek-tó (Round Lake), situated in Homoród Hills of the Eastern Carpathians in Romania, provides a continuous record of paleoclimatic and paleoenvironmental changes from the Early Holocene. In this study, we present a 7500-year-long high-resolution record of past climatic changes and signs of human impact recorded in a peat bog via integrating sedimentological, paleoecological and geochemical proxies. The basin of …
Geoarchaeological Study of Szálka and Vajda Kurgans (Great Hungarian Plain) Based on Radiocarbon and Geophysical Analyses
Two archaeologically unexplored mounds were studied in the area of the central Great Hungarian Plain. The age of the construction of the mounds was clarified on the basis of radiocarbon ( 14 C) age determination of buried soil layers. Different, later-building phases of the mounds were detected by pedological and geo-electric analyses of the human-made layers. The age of the buried soils was corrected for the reservoir age of the recent soils fou…
High-Precision Biogenic Fraction Analyses of Liquid Fuels by 14 C AMS at Hekal
The biocomponent ratio in liquid fuels as well as the usage of renewable resources for fuel consumption in the transport sector needs to be increased as a result of EU directive 2003/30/EC. Based on radiocarbon ( 14 C) measurements, it should be relatively simple and fast to measure the weight percentage of the fossil and biological sources by accelerator mass spectrometry (AMS) as recommended in the ASTM D 6866-12 and EN 16640 standards. In this…
Sealed Tube Combustion Method with MnO 2 for AMS 14 C Measurement
An effective sealed tube combustion method was designed with an MnO 2 oxidant for accelerator mass spectrometry radiocarbon (AMS 14 C) measurements. Different types of materials (oxalic acid, cellulose, sucrose, wood, collagen, graphite, and humic acid) were used to test the method. A normal borosilicate glass tube was used instead of quartz and the combustion was done at 550oC. The yield of the combustion is above 98% even in the case of the les…
High-resolution proxy record of the environmental response to climatic variations during transition MIS3/MIS2 and MIS2 in Central Europe
North Atlantic influences on climate conditions in East-Central Europe in the late Holocene reflected by flowstone compositions
Geology (32 works) · Geography (30 works) · Geology and Paleoclimatology Research (26 works) · Radiocarbon dating (26 works) · Paleontology (23 works) · Archaeology (20 works) · Physical geography (18 works) · Archaeology and ancient environmental studies (15 works) · Chemistry (10 works) · Holocene (10 works)