Denudation and Weathering Rates of Carbonate Landscapes From Meteoric 10Be/9Be Ratios

IF 3.5 2区 地球科学 Q1 GEOSCIENCES, MULTIDISCIPLINARY
H. Wittmann, J. Bouchez, D. Calmels, J. Gaillardet, D. A. Frick, N. Stroncik, ASTER Team, F. von Blanckenburg
{"title":"Denudation and Weathering Rates of Carbonate Landscapes From Meteoric 10Be/9Be Ratios","authors":"H. Wittmann,&nbsp;J. Bouchez,&nbsp;D. Calmels,&nbsp;J. Gaillardet,&nbsp;D. A. Frick,&nbsp;N. Stroncik,&nbsp;ASTER Team,&nbsp;F. von Blanckenburg","doi":"10.1029/2024JF007638","DOIUrl":null,"url":null,"abstract":"<p>Knowledge of the rates of carbonate rock denudation, the relative apportionment of chemical weathering versus physical erosion, and their sensitivity to climate, vegetation, and tectonics is essential for disclosing feedbacks within the carbon cycle and the functioning of karst landscapes that supply important services to humans. Currently, however, for carbonate lithologies, no method exists that allows to simultaneously partition denudation into erosion and weathering fluxes at spatial scales ranging from soil to watersheds. To determine total denudation rates in carbonate landscapes from an individual soil or river sample, we adapted a published framework that combines cosmogenic meteoric <sup>10</sup>Be as an atmospheric flux tracer with stable <sup>9</sup>Be that is released from rocks by weathering, to the limestone-dominated French Jura Mountains. By analyzing water, soil, sediment, travertine, and bedrock for <sup>10</sup>Be/<sup>9</sup>Be, major and trace elements, carbon stable isotopes and radiogenic strontium, we quantified contributions of Be from primary versus secondary carbonate phases and its release during weathering from carbonate bedrock versus silicate impurities. We calculated partitioning of Be between solids and solutes, and rates of catchment-wide (from sediment) and point source (from soil) denudation, weathering and erosion. Our results indicate that average denudation rates are 300–500 t/km<sup>2</sup>/yr. Denudation is dominated by weathering intensity (W/D) ratios of &gt;0.92, and a non-negligible contribution from deeper (below soil) weathering. Our rates agree to within less than a factor of two with decadal-scale denudation rates from combined suspended and dissolved fluxes, highlighting the substantial potential of this method for future Earth surface studies.</p>","PeriodicalId":15887,"journal":{"name":"Journal of Geophysical Research: Earth Surface","volume":"129 9","pages":""},"PeriodicalIF":3.5000,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JF007638","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Geophysical Research: Earth Surface","FirstCategoryId":"89","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1029/2024JF007638","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0

Abstract

Knowledge of the rates of carbonate rock denudation, the relative apportionment of chemical weathering versus physical erosion, and their sensitivity to climate, vegetation, and tectonics is essential for disclosing feedbacks within the carbon cycle and the functioning of karst landscapes that supply important services to humans. Currently, however, for carbonate lithologies, no method exists that allows to simultaneously partition denudation into erosion and weathering fluxes at spatial scales ranging from soil to watersheds. To determine total denudation rates in carbonate landscapes from an individual soil or river sample, we adapted a published framework that combines cosmogenic meteoric 10Be as an atmospheric flux tracer with stable 9Be that is released from rocks by weathering, to the limestone-dominated French Jura Mountains. By analyzing water, soil, sediment, travertine, and bedrock for 10Be/9Be, major and trace elements, carbon stable isotopes and radiogenic strontium, we quantified contributions of Be from primary versus secondary carbonate phases and its release during weathering from carbonate bedrock versus silicate impurities. We calculated partitioning of Be between solids and solutes, and rates of catchment-wide (from sediment) and point source (from soil) denudation, weathering and erosion. Our results indicate that average denudation rates are 300–500 t/km2/yr. Denudation is dominated by weathering intensity (W/D) ratios of >0.92, and a non-negligible contribution from deeper (below soil) weathering. Our rates agree to within less than a factor of two with decadal-scale denudation rates from combined suspended and dissolved fluxes, highlighting the substantial potential of this method for future Earth surface studies.

Abstract Image

从陨石 10Be/9Be 比率看碳酸盐地貌的剥蚀和风化速率
了解碳酸盐岩的剥蚀速率、化学风化与物理侵蚀的相对比例,以及它们对气候、植被和构造的敏感性,对于揭示碳循环中的反馈以及为人类提供重要服务的岩溶地貌的功能至关重要。然而,目前对于碳酸盐岩而言,还没有一种方法可以在从土壤到流域的空间尺度上将剥蚀同时划分为侵蚀通量和风化通量。为了从单个土壤或河流样本中确定碳酸盐岩地貌的总剥蚀率,我们在以石灰岩为主的法国汝拉山脉采用了一种已发表的框架,该框架将作为大气通量示踪剂的宇宙成因陨石 10Be 与岩石风化释放的稳定 9Be 结合在一起。通过分析水、土壤、沉积物、石灰岩和基岩中的 10Be/9Be、主要元素和痕量元素、碳稳定同位素和放射性锶,我们量化了原生碳酸盐相和次生碳酸盐相对铍的贡献,以及碳酸盐基岩和硅酸盐杂质在风化过程中对铍的释放。我们计算了铍在固体和溶质之间的分配,以及整个流域(来自沉积物)和点源(来自土壤)的剥蚀、风化和侵蚀速率。结果表明,平均剥蚀率为 300-500 吨/平方公里/年。剥蚀的主要原因是风化强度(W/D)比为 0.92,深层(土壤以下)风化的贡献不可忽略。我们的比率与悬浮和溶解通量的十年尺度剥蚀率相差不到 2 倍,突出表明了这种方法在未来地球表面研究中的巨大潜力。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Journal of Geophysical Research: Earth Surface
Journal of Geophysical Research: Earth Surface Earth and Planetary Sciences-Earth-Surface Processes
CiteScore
6.30
自引率
10.30%
发文量
162
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信