Cosmogenic Ne isotopes are stable and are routinely used for constraining the timing of events and the rate of surface change beyond the limit that can be studied with radionuclides ^10Be, ^26Al, and ^36Cl. Cosmogenic...Cosmogenic Ne isotopes are stable and are routinely used for constraining the timing of events and the rate of surface change beyond the limit that can be studied with radionuclides ^10Be, ^26Al, and ^36Cl. Cosmogenic Ne analysis can be used in quartz and in a range of other minerals. Analysis typically requires significantly less material than do cosmogenic ^10Be and ^26Al, opening up the technique for small samples--individual pebbles in fiver sediments, for example. Analysis is easier and faster than for radionuclides, not least because Ne measurements do not require significant chemical procedures. However, the presence of other sources of Ne in minerals tends to restrict the use of cosmogenic ^21Ne to old landscapes and long exposure durations. In this review we briefly outline the background of cosmogenic Ne production in rocks and minerals at the Earth＇s surface, then document the key uses of the technique by highlighting some earlier studies, and finish with a short perspective on the future of the technique.展开更多
In situ terrestrial cosmogenic nuclide （TCN） exposure dating using 10Be is one of the most successful techniques used to determine the ages of Quaternary deposits and yields data that enable the reconstruction of th...In situ terrestrial cosmogenic nuclide （TCN） exposure dating using 10Be is one of the most successful techniques used to determine the ages of Quaternary deposits and yields data that enable the reconstruction of the Quaternary glacial history of the Tibetan Plateau and the surrounding mountain ranges. Statistical analysis of TCN 10Be exposure ages, helps to reconstruct the history of glacial fluctuations and past climate changes on the Tibetan Plateau, differences in the timing of glacier advances among different regions. However, different versions of the Cosmic-Ray-prOduced NUclide Systematics on Earth （CRONUS-Earth） online calculator, which calculates and corrects the TCN ages of Quaternary glacial landforms, yield different results. For convenience in establishing contrasts among regions, in this paper, we recalculate 1848 10Be exposure ages from the Tibetan Plateau that were published from 1999 to 2017 using version 2.3 of the CRONUS-Earth calculator. We also compare the results obtained for 1594 10Be exposure ages using different versions （2.2, 2.3 and 3.0） of the CRONUS- Earth calculator. The results are as follows. （1） Approximately 97% of the exposure ages are less than 200 ka. A probability density curve of the exposure ages suggests that greater numbers of oscillations emerge during the Holocene, and the peaks correspond to the Little Ice Age, the 8.2 ka and 9.3 ka cold events; the main peak covers the period between 12 and 18 ka. （2） In most areas, the newer versions of the calculator produce older 10Be exposure ages. When different versions of the CRONUS-Earth calculator are used, approximately 29% of the 10Be exposure ages display maximum differences greater than 10 ka, and the maximum age difference for a single sample is 181.1 ka.展开更多
In situ terrestrial cosmogenic nuclide(TCN)has been widely applied to date the ages of Quaternary glacial deposits in Antarctica and plays an important role in reconstructing the glacial evolution and climate change.I...In situ terrestrial cosmogenic nuclide(TCN)has been widely applied to date the ages of Quaternary glacial deposits in Antarctica and plays an important role in reconstructing the glacial evolution and climate change.It helps to under‐stand the Antarctic ice sheet's evolution process in Quaternary and shed light on the application of Cosmogenic Nu‐clide exposure dating technique in Glacial Geomorphology.In this paper,we retrieved 49510Be age samples in Ant‐arctica from literature published between 2004 and 2020 and recalculated the TCN ages using version 3.0 online cal‐culator of Cosmic-Ray Produced Nuclide Systematics on Earth(CRONUS-Earth).Several conclusions can be drawn from the results:(1)75%of the exposure ages are younger than 400 ka,and 91%younger than 1,100 ka.Northern Antarctic Peninsula exposure result is visibly younger than the main glaciers in East Antarctica due to climate change and geological evaluation since the LGM(Last Glacial Maximum).(2)TCN ages are relevant to the samples'relative positions in the Antarctic continent,but a relationship between their ages and elevations is yet to be determined based on the collected data.展开更多
In situ cosmogenic ^(10)Be in quartz from loess deposited in the last 2,000,000 a is considered to have been derived mainly from initial ^(10)Be in source regions and it bears abundant information about changes in ero...In situ cosmogenic ^(10)Be in quartz from loess deposited in the last 2,000,000 a is considered to have been derived mainly from initial ^(10)Be in source regions and it bears abundant information about changes in erosion rates of source regions. As [have been estimated, the concentrations of 'in situ cosmogenic ^(10)Be' in quartz from samples GL47(L1) andGL83 (L2) collected from the Luochuan loess section are 5×10~5 atom/g and 2.2×10~6 atom/g, respectively. As calculated on the basis of the above estimates, the erosion rates of the source regions are: εBeL1=1.5×10^(-3) cm/a for the L1 period (10,000—90,000 a) and εBeL2=3.8×10^(-4) cm/a for the L2 period (130,000—190,000 a). Studies of 'in situ cosmogeuic ^(10)Be' in quartz from loess at deeper levels are expected to be applied to ^(10)Be dating of loess strata.展开更多
基金supported by the basic scientific research fund, Institute of Geology, China Earthquake Administration (Grant Nos. IGCEA1504 and IGCEA1417)
文摘Cosmogenic Ne isotopes are stable and are routinely used for constraining the timing of events and the rate of surface change beyond the limit that can be studied with radionuclides ^10Be, ^26Al, and ^36Cl. Cosmogenic Ne analysis can be used in quartz and in a range of other minerals. Analysis typically requires significantly less material than do cosmogenic ^10Be and ^26Al, opening up the technique for small samples--individual pebbles in fiver sediments, for example. Analysis is easier and faster than for radionuclides, not least because Ne measurements do not require significant chemical procedures. However, the presence of other sources of Ne in minerals tends to restrict the use of cosmogenic ^21Ne to old landscapes and long exposure durations. In this review we briefly outline the background of cosmogenic Ne production in rocks and minerals at the Earth＇s surface, then document the key uses of the technique by highlighting some earlier studies, and finish with a short perspective on the future of the technique.
基金supported by the National Natural Science Foundation of China(Grant No.41503054)the China Postdoctoral Science Foundation(2015M582728)+1 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)(Grant No.164320H116)the Yulong Mountain tourism development and management committee special project
文摘In situ terrestrial cosmogenic nuclide （TCN） exposure dating using 10Be is one of the most successful techniques used to determine the ages of Quaternary deposits and yields data that enable the reconstruction of the Quaternary glacial history of the Tibetan Plateau and the surrounding mountain ranges. Statistical analysis of TCN 10Be exposure ages, helps to reconstruct the history of glacial fluctuations and past climate changes on the Tibetan Plateau, differences in the timing of glacier advances among different regions. However, different versions of the Cosmic-Ray-prOduced NUclide Systematics on Earth （CRONUS-Earth） online calculator, which calculates and corrects the TCN ages of Quaternary glacial landforms, yield different results. For convenience in establishing contrasts among regions, in this paper, we recalculate 1848 10Be exposure ages from the Tibetan Plateau that were published from 1999 to 2017 using version 2.3 of the CRONUS-Earth calculator. We also compare the results obtained for 1594 10Be exposure ages using different versions （2.2, 2.3 and 3.0） of the CRONUS- Earth calculator. The results are as follows. （1） Approximately 97% of the exposure ages are less than 200 ka. A probability density curve of the exposure ages suggests that greater numbers of oscillations emerge during the Holocene, and the peaks correspond to the Little Ice Age, the 8.2 ka and 9.3 ka cold events; the main peak covers the period between 12 and 18 ka. （2） In most areas, the newer versions of the calculator produce older 10Be exposure ages. When different versions of the CRONUS-Earth calculator are used, approximately 29% of the 10Be exposure ages display maximum differences greater than 10 ka, and the maximum age difference for a single sample is 181.1 ka.
基金the National Natural Science Foundation of China(No.41971009 and No.41503054)the China Postdoctoral Science Foundation(No.2015M582728)the Priority Academic Program Development of Jiangsu Higher Education Institutions(No.64320H116).
文摘In situ terrestrial cosmogenic nuclide(TCN)has been widely applied to date the ages of Quaternary glacial deposits in Antarctica and plays an important role in reconstructing the glacial evolution and climate change.It helps to under‐stand the Antarctic ice sheet's evolution process in Quaternary and shed light on the application of Cosmogenic Nu‐clide exposure dating technique in Glacial Geomorphology.In this paper,we retrieved 49510Be age samples in Ant‐arctica from literature published between 2004 and 2020 and recalculated the TCN ages using version 3.0 online cal‐culator of Cosmic-Ray Produced Nuclide Systematics on Earth(CRONUS-Earth).Several conclusions can be drawn from the results:(1)75%of the exposure ages are younger than 400 ka,and 91%younger than 1,100 ka.Northern Antarctic Peninsula exposure result is visibly younger than the main glaciers in East Antarctica due to climate change and geological evaluation since the LGM(Last Glacial Maximum).(2)TCN ages are relevant to the samples'relative positions in the Antarctic continent,but a relationship between their ages and elevations is yet to be determined based on the collected data.
基金This work was financially supported both by the Swiss National Science Foundation and by the National Natural Science Foundation of China
文摘In situ cosmogenic ^(10)Be in quartz from loess deposited in the last 2,000,000 a is considered to have been derived mainly from initial ^(10)Be in source regions and it bears abundant information about changes in erosion rates of source regions. As [have been estimated, the concentrations of 'in situ cosmogenic ^(10)Be' in quartz from samples GL47(L1) andGL83 (L2) collected from the Luochuan loess section are 5×10~5 atom/g and 2.2×10~6 atom/g, respectively. As calculated on the basis of the above estimates, the erosion rates of the source regions are: εBeL1=1.5×10^(-3) cm/a for the L1 period (10,000—90,000 a) and εBeL2=3.8×10^(-4) cm/a for the L2 period (130,000—190,000 a). Studies of 'in situ cosmogeuic ^(10)Be' in quartz from loess at deeper levels are expected to be applied to ^(10)Be dating of loess strata.
