The Experts below are selected from a list of 276 Experts worldwide ranked by ideXlab platform
M Rybníček - One of the best experts on this subject based on the ideXlab platform.
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the best possible time resolution how precise could a radiocarbon Dating Method be
Radiocarbon, 2019Co-Authors: I Svetlik, A. J. T. Jull, Mihály Molnár, Pavel P. Povinec, T Kolář, P Demján, Veronika Brychova, D Dreslerová, Pachnerova K Brabcova, M RybníčekAbstract:Today, accelerator mass spectrometry (AMS) technology enables us to carry out very precise measurements of radiocarbon (14C). Unfortunately, due to fluctuations in the 14C calibration curve, the resulting calibrated time intervals vary from decades up to centuries in calibrated age. Within a time scale of several decades, we can find several time intervals on the 14C calibration curve which correspond with periods of rapid increases in atmospheric 14CO2 activity. Some of these “high slope” parts of the calibration curve could be used for fine time resolution for radiocarbon Dating of individual samples. Nevertheless, there are certain limitations owing to the properties of the samples measured. We have prepared a time-resolution curve for the 14C Dating Method, applying calibration curve IntCal13 and assuming an uncertainty of 14C analyses ±15 yr BP (for recent samples). Our curve of the time resolution covers the last 50 ka. We found several time intervals with time resolution below 50 yr BP for the last 3 ka. Several time intervals which can enable substantially better time resolution compared to neighboring parts of the calibration curve were also found for periods older than 3 ka.
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The Best possible Time resolution: How precise could a Radiocarbon Dating Method be?
Radiocarbon, 2019Co-Authors: I Svetlik, A. J. T. Jull, Mihály Molnár, Pavel P. Povinec, T Kolář, P Demján, K Pachnerova Brabcova, Veronika Brychova, D Dreslerová, M RybníčekAbstract:Today, accelerator mass spectrometry (AMS) technology enables us to carry out very precise measurements of radiocarbon (14C). Unfortunately, due to fluctuations in the 14C calibration curve, the resulting calibrated time intervals vary from decades up to centuries in calibrated age. Within a time scale of several decades, we can find several time intervals on the 14C calibration curve which correspond with periods of rapid increases in atmospheric 14CO2 activity. Some of these “high slope” parts of the calibration curve could be used for fine time resolution for radiocarbon Dating of individual samples. Nevertheless, there are certain limitations owing to the properties of the samples measured. We have prepared a time-resolution curve for the 14C Dating Method, applying calibration curve IntCal13 and assuming an uncertainty of 14C analyses ±15 yr BP (for recent samples). Our curve of the time resolution covers the last 50 ka. We found several time intervals with time resolution below 50 yr BP for the last 3 ka. Several time intervals which can enable substantially better time resolution compared to neighboring parts of the calibration curve were also found for periods older than 3 ka.
Randall White - One of the best experts on this subject based on the ideXlab platform.
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uranium thorium Dating Method and palaeolithic rock art
Quaternary International, 2017Co-Authors: Georges Sauvet, Raphaëlle Bourrillon, Margaret W. Conkey, Carole Fritz, Olivia Rivero Vilá, Gilles Tosello, Diego Garatemaidagan, Randall WhiteAbstract:Abstract Dramatic progress was seen in 14C-Dating with the introduction of accelerator mass spectroscopy (AMS) which made possible the direct Dating of prehistoric artworks painted or drawn with charcoal. However, in the case of engravings and red paintings, only indirect Methods can be used that allow us to date deposits that have covered the works over time (TL, U/Th, oxalates, etc.). The uranium/thorium Dating Method gives reliable and relatively precise results in the case of massive speleothems, because the sampling is carried out at the heart of the material where the hypothesis of a closed system (that is, no exchange with the outside environment) is justified in most cases. Unfortunately, the situation is quite different in the case of thin layers of calcite that overlie Palaeolithic cave drawings. The conditions under which calcite forms depend largely on the hydrologic activity, which has greatly varied over the course of the Upper Palaeolithic and Holocene. In many cases, we can see that the growth of speleothems stopped during much of the Upper Palaeolithic. Consequently the ages obtained are minimum ages (terminus ante quem) which are frequently much younger than the real ages of the underlying artworks. Moreover, a much more serious but rarely considered source of error contradicts the assumption of a closed system. In thin layers of carbonate deposits and in damp media, the uranium incorporated into the calcite during its crystallization may be partially eliminated because of its solubility in water. Uranium leaching causes an artificial increase of the age that may reach considerable proportions (e.g. a negative hand in a cave in Borneo was dated to 27,000 years by U/Th whereas its 14C age was only 8–10,000 cal BP; Plagnes et al., 2003). Due to these two contradictory sources of error, the dates given by the U/Th Method may prove to be younger or older, with deviations that are much larger than the standard deviations given by laboratories. As a result it is nearly impossible and very dangerous to base archaeological reasoning on U/Th ages of Palaeolithic artworks, so long as the dates are not confirmed by an independent Method, Dating the carbonates in the same samples by 14C being the best means of detecting anomalies. The application of the U/Th Method for the Dating of prehistoric rock art is still experimental. Technical improvements (for less damageable sampling) and fundamental research on the causes of errors are needed.
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Uranium–thorium Dating Method and Palaeolithic rock art
Quaternary International, 2017Co-Authors: Georges Sauvet, Raphaëlle Bourrillon, Margaret W. Conkey, Carole Fritz, Diego Garate-maidagan, Olivia Rivero Vilá, Gilles Tosello, Randall WhiteAbstract:Abstract Dramatic progress was seen in 14C-Dating with the introduction of accelerator mass spectroscopy (AMS) which made possible the direct Dating of prehistoric artworks painted or drawn with charcoal. However, in the case of engravings and red paintings, only indirect Methods can be used that allow us to date deposits that have covered the works over time (TL, U/Th, oxalates, etc.). The uranium/thorium Dating Method gives reliable and relatively precise results in the case of massive speleothems, because the sampling is carried out at the heart of the material where the hypothesis of a closed system (that is, no exchange with the outside environment) is justified in most cases. Unfortunately, the situation is quite different in the case of thin layers of calcite that overlie Palaeolithic cave drawings. The conditions under which calcite forms depend largely on the hydrologic activity, which has greatly varied over the course of the Upper Palaeolithic and Holocene. In many cases, we can see that the growth of speleothems stopped during much of the Upper Palaeolithic. Consequently the ages obtained are minimum ages (terminus ante quem) which are frequently much younger than the real ages of the underlying artworks. Moreover, a much more serious but rarely considered source of error contradicts the assumption of a closed system. In thin layers of carbonate deposits and in damp media, the uranium incorporated into the calcite during its crystallization may be partially eliminated because of its solubility in water. Uranium leaching causes an artificial increase of the age that may reach considerable proportions (e.g. a negative hand in a cave in Borneo was dated to 27,000 years by U/Th whereas its 14C age was only 8–10,000 cal BP; Plagnes et al., 2003). Due to these two contradictory sources of error, the dates given by the U/Th Method may prove to be younger or older, with deviations that are much larger than the standard deviations given by laboratories. As a result it is nearly impossible and very dangerous to base archaeological reasoning on U/Th ages of Palaeolithic artworks, so long as the dates are not confirmed by an independent Method, Dating the carbonates in the same samples by 14C being the best means of detecting anomalies. The application of the U/Th Method for the Dating of prehistoric rock art is still experimental. Technical improvements (for less damageable sampling) and fundamental research on the causes of errors are needed.
I Svetlik - One of the best experts on this subject based on the ideXlab platform.
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the best possible time resolution how precise could a radiocarbon Dating Method be
Radiocarbon, 2019Co-Authors: I Svetlik, A. J. T. Jull, Mihály Molnár, Pavel P. Povinec, T Kolář, P Demján, Veronika Brychova, D Dreslerová, Pachnerova K Brabcova, M RybníčekAbstract:Today, accelerator mass spectrometry (AMS) technology enables us to carry out very precise measurements of radiocarbon (14C). Unfortunately, due to fluctuations in the 14C calibration curve, the resulting calibrated time intervals vary from decades up to centuries in calibrated age. Within a time scale of several decades, we can find several time intervals on the 14C calibration curve which correspond with periods of rapid increases in atmospheric 14CO2 activity. Some of these “high slope” parts of the calibration curve could be used for fine time resolution for radiocarbon Dating of individual samples. Nevertheless, there are certain limitations owing to the properties of the samples measured. We have prepared a time-resolution curve for the 14C Dating Method, applying calibration curve IntCal13 and assuming an uncertainty of 14C analyses ±15 yr BP (for recent samples). Our curve of the time resolution covers the last 50 ka. We found several time intervals with time resolution below 50 yr BP for the last 3 ka. Several time intervals which can enable substantially better time resolution compared to neighboring parts of the calibration curve were also found for periods older than 3 ka.
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The Best possible Time resolution: How precise could a Radiocarbon Dating Method be?
Radiocarbon, 2019Co-Authors: I Svetlik, A. J. T. Jull, Mihály Molnár, Pavel P. Povinec, T Kolář, P Demján, K Pachnerova Brabcova, Veronika Brychova, D Dreslerová, M RybníčekAbstract:Today, accelerator mass spectrometry (AMS) technology enables us to carry out very precise measurements of radiocarbon (14C). Unfortunately, due to fluctuations in the 14C calibration curve, the resulting calibrated time intervals vary from decades up to centuries in calibrated age. Within a time scale of several decades, we can find several time intervals on the 14C calibration curve which correspond with periods of rapid increases in atmospheric 14CO2 activity. Some of these “high slope” parts of the calibration curve could be used for fine time resolution for radiocarbon Dating of individual samples. Nevertheless, there are certain limitations owing to the properties of the samples measured. We have prepared a time-resolution curve for the 14C Dating Method, applying calibration curve IntCal13 and assuming an uncertainty of 14C analyses ±15 yr BP (for recent samples). Our curve of the time resolution covers the last 50 ka. We found several time intervals with time resolution below 50 yr BP for the last 3 ka. Several time intervals which can enable substantially better time resolution compared to neighboring parts of the calibration curve were also found for periods older than 3 ka.
Georges Sauvet - One of the best experts on this subject based on the ideXlab platform.
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uranium thorium Dating Method and palaeolithic rock art
Quaternary International, 2017Co-Authors: Georges Sauvet, Raphaëlle Bourrillon, Margaret W. Conkey, Carole Fritz, Olivia Rivero Vilá, Gilles Tosello, Diego Garatemaidagan, Randall WhiteAbstract:Abstract Dramatic progress was seen in 14C-Dating with the introduction of accelerator mass spectroscopy (AMS) which made possible the direct Dating of prehistoric artworks painted or drawn with charcoal. However, in the case of engravings and red paintings, only indirect Methods can be used that allow us to date deposits that have covered the works over time (TL, U/Th, oxalates, etc.). The uranium/thorium Dating Method gives reliable and relatively precise results in the case of massive speleothems, because the sampling is carried out at the heart of the material where the hypothesis of a closed system (that is, no exchange with the outside environment) is justified in most cases. Unfortunately, the situation is quite different in the case of thin layers of calcite that overlie Palaeolithic cave drawings. The conditions under which calcite forms depend largely on the hydrologic activity, which has greatly varied over the course of the Upper Palaeolithic and Holocene. In many cases, we can see that the growth of speleothems stopped during much of the Upper Palaeolithic. Consequently the ages obtained are minimum ages (terminus ante quem) which are frequently much younger than the real ages of the underlying artworks. Moreover, a much more serious but rarely considered source of error contradicts the assumption of a closed system. In thin layers of carbonate deposits and in damp media, the uranium incorporated into the calcite during its crystallization may be partially eliminated because of its solubility in water. Uranium leaching causes an artificial increase of the age that may reach considerable proportions (e.g. a negative hand in a cave in Borneo was dated to 27,000 years by U/Th whereas its 14C age was only 8–10,000 cal BP; Plagnes et al., 2003). Due to these two contradictory sources of error, the dates given by the U/Th Method may prove to be younger or older, with deviations that are much larger than the standard deviations given by laboratories. As a result it is nearly impossible and very dangerous to base archaeological reasoning on U/Th ages of Palaeolithic artworks, so long as the dates are not confirmed by an independent Method, Dating the carbonates in the same samples by 14C being the best means of detecting anomalies. The application of the U/Th Method for the Dating of prehistoric rock art is still experimental. Technical improvements (for less damageable sampling) and fundamental research on the causes of errors are needed.
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Uranium–thorium Dating Method and Palaeolithic rock art
Quaternary International, 2017Co-Authors: Georges Sauvet, Raphaëlle Bourrillon, Margaret W. Conkey, Carole Fritz, Diego Garate-maidagan, Olivia Rivero Vilá, Gilles Tosello, Randall WhiteAbstract:Abstract Dramatic progress was seen in 14C-Dating with the introduction of accelerator mass spectroscopy (AMS) which made possible the direct Dating of prehistoric artworks painted or drawn with charcoal. However, in the case of engravings and red paintings, only indirect Methods can be used that allow us to date deposits that have covered the works over time (TL, U/Th, oxalates, etc.). The uranium/thorium Dating Method gives reliable and relatively precise results in the case of massive speleothems, because the sampling is carried out at the heart of the material where the hypothesis of a closed system (that is, no exchange with the outside environment) is justified in most cases. Unfortunately, the situation is quite different in the case of thin layers of calcite that overlie Palaeolithic cave drawings. The conditions under which calcite forms depend largely on the hydrologic activity, which has greatly varied over the course of the Upper Palaeolithic and Holocene. In many cases, we can see that the growth of speleothems stopped during much of the Upper Palaeolithic. Consequently the ages obtained are minimum ages (terminus ante quem) which are frequently much younger than the real ages of the underlying artworks. Moreover, a much more serious but rarely considered source of error contradicts the assumption of a closed system. In thin layers of carbonate deposits and in damp media, the uranium incorporated into the calcite during its crystallization may be partially eliminated because of its solubility in water. Uranium leaching causes an artificial increase of the age that may reach considerable proportions (e.g. a negative hand in a cave in Borneo was dated to 27,000 years by U/Th whereas its 14C age was only 8–10,000 cal BP; Plagnes et al., 2003). Due to these two contradictory sources of error, the dates given by the U/Th Method may prove to be younger or older, with deviations that are much larger than the standard deviations given by laboratories. As a result it is nearly impossible and very dangerous to base archaeological reasoning on U/Th ages of Palaeolithic artworks, so long as the dates are not confirmed by an independent Method, Dating the carbonates in the same samples by 14C being the best means of detecting anomalies. The application of the U/Th Method for the Dating of prehistoric rock art is still experimental. Technical improvements (for less damageable sampling) and fundamental research on the causes of errors are needed.
N. S. Bortnikov - One of the best experts on this subject based on the ideXlab platform.
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U–Th–He Dating of Pyrite from the Uzelga Copper-Zinc Massive Sulfide Deposit (South Urals, Russia): First Application of a New Geochronometer
Doklady Earth Sciences, 2019Co-Authors: O V Yakubovich, O. V. Zarubina, N. V. Bryanskiy, S. I. Dril, B M Gorokhovskii, A B Kotov, I V Vikentyev, N. S. BortnikovAbstract:Based on a study of pyrite from the Uzelga Cu–Zn volcanogenic massive sulfide (VMS) deposit (South Urals) the age of ore mineralization was first determined with the direct age Dating Method, based on the fraction of radiogenic helium, incorporated into the pyrite crystal lattice from submicron inclusions of U and Th minerals. Taking into account the measurement errors, the obtained age of 377 ± 8 Ma (MSWD = 1.2) is quite consistent with the independent age dates available for the ore mineralization (Late Eifelian–Early Givetian, 385–390 Ma).
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U–Th–He Dating of Pyrite from the Uzelga Copper-Zinc Massive Sulfide Deposit (South Urals, Russia): First Application of a New Geochronometer
Doklady Earth Sciences, 2019Co-Authors: O V Yakubovich, O. V. Zarubina, N. V. Bryanskiy, S. I. Dril, B M Gorokhovskii, A B Kotov, I V Vikentyev, N. S. BortnikovAbstract:Based on a study of pyrite from the Uzelga Cu–Zn volcanogenic massive sulfide (VMS) deposit (South Urals) the age of ore mineralization was first determined with the direct age Dating Method, based on the fraction of radiogenic helium, incorporated into the pyrite crystal lattice from submicron inclusions of U and Th minerals. Taking into account the measurement errors, the obtained age of 377 ± 8 Ma (MSWD = 1.2) is quite consistent with the independent age dates available for the ore mineralization (Late Eifelian–Early Givetian, 385–390 Ma).
