岩浆生长的等温热释光年代测定--德国 Bleßberg 2 号洞穴的案例研究

IF 16.4 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Accounts of Chemical Research Pub Date : 2024-09-21 DOI:10.1016/j.quageo.2024.101628

Junjie Zhang , Jennifer Klose , Denis Scholz , Norbert Marwan , Sebastian F.M. Breitenbach , Lutz Katzschmann , Dennis Kraemer , Sumiko Tsukamoto

{"title":"岩浆生长的等温热释光年代测定--德国 Bleßberg 2 号洞穴的案例研究","authors":"Junjie Zhang , Jennifer Klose , Denis Scholz , Norbert Marwan , Sebastian F.M. Breitenbach , Lutz Katzschmann , Dennis Kraemer , Sumiko Tsukamoto","doi":"10.1016/j.quageo.2024.101628","DOIUrl":null,"url":null,"abstract":"<div><div>Speleothems are a key archive of past climatic and environmental changes. <sup>230</sup>Th/U dating is the most commonly used method to determine speleothem ages. However, incorporation of non-radiogenic thorium may hamper <sup>230</sup>Th/U dating, and samples older than 600 ka also remain out-of-reach. Calcite exhibits a thermoluminescence (TL) signal at 280 °C with a high characteristic saturation dose, and provides significant potential to date carbonate samples over several million years. Hitherto, the application of TL dating for calcite has mainly been hindered by two factors: 1) a spurious TL signal occurring in the high temperature range, and 2) non-uniform dose rate due to U-series disequilibrium. Here we test an isothermal TL (ITL) dating method on a speleothem sample from Bleßberg cave 2, Germany. We show that the ITL signal measured at 240 °C can completely remove the 280 °C TL peak with a negligible TL contribution from the higher temperature range, thus reducing the influence from the spurious signal. The time-dependent dose rate variation can be simulated using the initial radioactivity of <sup>238</sup>U, <sup>234</sup>U, <sup>230</sup>Th and their decay constants. We use the <sup>230</sup>Th/U dating method to provide precise and accurate radiometric ages documenting that the speleothem grew between 425.5 ± 5.4 and 320.5 ± 9.7 ka. The ITL ages (421 ± 23 to 311 ± 23 ka) of four subsamples from the speleothem are consistent with the <sup>230</sup>Th/U ages at isochronous sampling positions, showing the general reliability of the ITL dating method. ITL dating provides a pathway to construct chronologies for palaeoclimate reconstructions for speleothems beyond the range of the <sup>230</sup>Th/U-method and for samples that are unsuitable for U-series dating methods.</div></div>","PeriodicalId":1,"journal":{"name":"Accounts of Chemical Research","volume":null,"pages":null},"PeriodicalIF":16.4000,"publicationDate":"2024-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Isothermal thermoluminescence dating of speleothem growth – A case study from Bleßberg cave 2, Germany\",\"authors\":\"Junjie Zhang , Jennifer Klose , Denis Scholz , Norbert Marwan , Sebastian F.M. Breitenbach , Lutz Katzschmann , Dennis Kraemer , Sumiko Tsukamoto\",\"doi\":\"10.1016/j.quageo.2024.101628\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Speleothems are a key archive of past climatic and environmental changes. <sup>230</sup>Th/U dating is the most commonly used method to determine speleothem ages. However, incorporation of non-radiogenic thorium may hamper <sup>230</sup>Th/U dating, and samples older than 600 ka also remain out-of-reach. Calcite exhibits a thermoluminescence (TL) signal at 280 °C with a high characteristic saturation dose, and provides significant potential to date carbonate samples over several million years. Hitherto, the application of TL dating for calcite has mainly been hindered by two factors: 1) a spurious TL signal occurring in the high temperature range, and 2) non-uniform dose rate due to U-series disequilibrium. Here we test an isothermal TL (ITL) dating method on a speleothem sample from Bleßberg cave 2, Germany. We show that the ITL signal measured at 240 °C can completely remove the 280 °C TL peak with a negligible TL contribution from the higher temperature range, thus reducing the influence from the spurious signal. The time-dependent dose rate variation can be simulated using the initial radioactivity of <sup>238</sup>U, <sup>234</sup>U, <sup>230</sup>Th and their decay constants. We use the <sup>230</sup>Th/U dating method to provide precise and accurate radiometric ages documenting that the speleothem grew between 425.5 ± 5.4 and 320.5 ± 9.7 ka. The ITL ages (421 ± 23 to 311 ± 23 ka) of four subsamples from the speleothem are consistent with the <sup>230</sup>Th/U ages at isochronous sampling positions, showing the general reliability of the ITL dating method. ITL dating provides a pathway to construct chronologies for palaeoclimate reconstructions for speleothems beyond the range of the <sup>230</sup>Th/U-method and for samples that are unsuitable for U-series dating methods.</div></div>\",\"PeriodicalId\":1,\"journal\":{\"name\":\"Accounts of Chemical Research\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":16.4000,\"publicationDate\":\"2024-09-21\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Accounts of Chemical Research\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S1871101424001328\",\"RegionNum\":1,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"CHEMISTRY, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Accounts of Chemical Research","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1871101424001328","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}

引用次数: 0

摘要

岩浆化石是过去气候和环境变化的重要档案。230Th/U 测定是确定岩浆年龄最常用的方法。然而，非辐射钍的加入可能会妨碍 230Th/U 测定，而且 600 ka 以上的样本仍然无法测定。方解石在 280 °C 时会发出热释光（TL）信号，其特征饱和剂量很高，这为确定几百万年前碳酸盐样本的年代提供了巨大的潜力。迄今为止，方解石的 TL 测定主要受到两个因素的阻碍：1) 高温范围内出现的虚假 TL 信号；2) U 系列不平衡导致的非均匀剂量率。在这里，我们对来自德国 Bleßberg 2 号洞穴的岩浆岩样本进行了等温 TL（ITL）测年方法的测试。结果表明，在 240 ℃ 测量的 ITL 信号可以完全消除 280 ℃ 的 TL 峰值，较高温度范围的 TL 贡献可以忽略不计，从而减少了杂散信号的影响。可以利用 238U、234U 和 230Th 的初始放射性及其衰变常数来模拟随时间变化的剂量率变化。我们使用 230Th/U 测定法提供了精确的放射性年龄，记录了岩洞在 425.5 ± 5.4 ka 到 320.5 ± 9.7 ka 之间的生长过程。从岩浆池中提取的四个子样本的 ITL 年龄（421 ± 23 至 311 ± 23 ka）与等时取样位置的 230Th/U 年龄一致，表明 ITL 测定法总体上是可靠的。ITL 测定法为超出 230Th/U 测定法范围的岩浆岩和不适合 U 系列测年法的样本提供了构建古气候重建年代学的途径。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

查看原文本刊更多论文

Isothermal thermoluminescence dating of speleothem growth – A case study from Bleßberg cave 2, Germany

Speleothems are a key archive of past climatic and environmental changes. ²³⁰Th/U dating is the most commonly used method to determine speleothem ages. However, incorporation of non-radiogenic thorium may hamper ²³⁰Th/U dating, and samples older than 600 ka also remain out-of-reach. Calcite exhibits a thermoluminescence (TL) signal at 280 °C with a high characteristic saturation dose, and provides significant potential to date carbonate samples over several million years. Hitherto, the application of TL dating for calcite has mainly been hindered by two factors: 1) a spurious TL signal occurring in the high temperature range, and 2) non-uniform dose rate due to U-series disequilibrium. Here we test an isothermal TL (ITL) dating method on a speleothem sample from Bleßberg cave 2, Germany. We show that the ITL signal measured at 240 °C can completely remove the 280 °C TL peak with a negligible TL contribution from the higher temperature range, thus reducing the influence from the spurious signal. The time-dependent dose rate variation can be simulated using the initial radioactivity of ²³⁸U, ²³⁴U, ²³⁰Th and their decay constants. We use the ²³⁰Th/U dating method to provide precise and accurate radiometric ages documenting that the speleothem grew between 425.5 ± 5.4 and 320.5 ± 9.7 ka. The ITL ages (421 ± 23 to 311 ± 23 ka) of four subsamples from the speleothem are consistent with the ²³⁰Th/U ages at isochronous sampling positions, showing the general reliability of the ITL dating method. ITL dating provides a pathway to construct chronologies for palaeoclimate reconstructions for speleothems beyond the range of the ²³⁰Th/U-method and for samples that are unsuitable for U-series dating methods.

求助全文

通过发布文献求助，成功后即可免费获取论文全文。去求助

来源期刊

Accounts of Chemical Research 化学-化学综合

CiteScore

31.40

自引率

1.10%

发文量

312

审稿时长

2 months

期刊介绍： Accounts of Chemical Research presents short, concise and critical articles offering easy-to-read overviews of basic research and applications in all areas of chemistry and biochemistry. These short reviews focus on research from the author’s own laboratory and are designed to teach the reader about a research project. In addition, Accounts of Chemical Research publishes commentaries that give an informed opinion on a current research problem. Special Issues online are devoted to a single topic of unusual activity and significance. Accounts of Chemical Research replaces the traditional article abstract with an article "Conspectus." These entries synopsize the research affording the reader a closer look at the content and significance of an article. Through this provision of a more detailed description of the article contents, the Conspectus enhances the article's discoverability by search engines and the exposure for the research.