• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Quaternary geochronology >High-resolution age modelling of peat bogs from northern Alberta, Canada, using pre- and post-bomb C-14, Pb-210 and historical cryptotephra
【24h】

High-resolution age modelling of peat bogs from northern Alberta, Canada, using pre- and post-bomb C-14, Pb-210 and historical cryptotephra

机译：来自加拿大北·阿尔伯塔北部的泥炭沼泽的高分辨率年龄造型，使用预先炸弹C-14，PB-210和历史cryptotephra

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

High-resolution studies of peat profiles are frequently undertaken to investigate natural and anthropogenic disturbances over time. However, overlapping profiles of the most commonly applied age-dating techniques, including C-14 and Pb-210, often show significant offsets ( decadal) and biases that can be difficult to resolve. Here we investigate variations in the chronometers and individual site histories from six ombrotrophic peat bogs in central and northern Alberta. Dates produced using pre- and post-bomb C-14, Pb-210 (corroborated with Cs-137 and Am-241), and cryptotephra peaks, are compared and then integrated using OxCal's P_Sequence function to produce a single Bayesian age model. Environmental histories for each site obtained using physical and chemical characteristics of the peat cores, e.g. macrofossils, humification, ash content, and dry density, provide important constraints for the models by highlighting periods with significant changes in accumulation rate, e.g. fire events, permafrost development, and prolonged surficial drying. Despite variable environmental histories, it is possible to produce high-resolution age-depth models for each core sequence. Consistent offsets between C-14 and Pb-210 dates pre-1960s are seen at five of the six sites, but tephra-corrected Pb-210 data can be used to produce more coherent models at three of these sites. Processes such as permafrost development and thaw, surficial drying and local fires can disrupt the normal processes by which chronological markers and environmental records are incorporated in the peat record. In consequence, applying standard dating methodologies to these records will result in even greater uncertainties and discrepancies between the different dating tools. These results show that using any single method to accurately date peat profiles where accumulation has not been uniform over time may be unreliable, but a comprehensive multi-method investigation paired with the application of Bayesian
机译：经常进行泥炭型材的高分辨率研究，以随着时间的推移来研究自然和人为紊乱。然而，包括C-14和PB-210的最常用的年龄和最常约会技术的重叠简介通常显示出显着的偏移（＆ decadal）和偏置，这可能难以解决。在这里，我们研究了中央和北艾伯塔北部的六个令人幕府泥炭沼泽中计时器和单个位点历史的变化。使用预先和炸弹后C-14，PB-210（用CS-137和AM-241证实）和Cryptotephra峰产生的日期，然后使用oxcal的P_Sequence函数集成来产生单一的贝叶斯年龄模型。例如，使用泥炭芯的物理和化学特性获得的每个网站的环境历史，例如，通过突出显示具有显着变化的累积率变化，为模型提供重要限制，为模型提供重要的约束火灾事件，永久性发展，延长曲面干燥。尽管有变量环境历史，但是可以为每个核心序列产生高分辨率年龄深度模型。在六个站点中的五个中可以看到C-14和PB-210之间的一致偏移，但是在六个站点中的五个中可以看到，但是可以使用Tephars校正的PB-210数据来在其中三个站点中产生更多相干的模型。 Pumafrost开发和解冻等过程可以破坏时间中标记和环境记录中的正常过程中的正常过程。因此，将标准约会方法应用于这些记录将导致不同约会工具之间的更大的不确定性和差异。这些结果表明，使用任何单一方法来准确地涂抹泥炭型材，随着时间的推移，积累并未均匀地可能是不可靠的，但是与贝叶斯的应用配对综合的多方法调查

著录项

相似文献

  • 外文文献
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号