气候变化领域集成服务门户(CCPortal): Seismic evidence of glacial deposits inhibiting weathering of local bedrock at a snow-dominated subalpine watershed

CCPortal

DOI	10.1016/j.epsl.2020.116517
	Seismic evidence of glacial deposits inhibiting weathering of local bedrock at a snow-dominated subalpine watershed
	Wang W.; Chen P.; Dueker K.; Lee E.-J.; Mu D.; Keifer I.
发表日期	2020
ISSN	0012821X
卷号	549
英文摘要	Previously glaciated landscapes are often covered with glacial sediments with poorly sorted particles. The thickness of glacial sediments can reach hundreds of meters. These sediments, which have experienced high intensity erosion through glacial transportation, are susceptible to chemical weathering processes because of the increased reactive mineral surfaces induced via erosion. Infiltrated meteoric water will first attack the glacial sediments, becoming (partially) saturated with weathering products, before interacting with the local bedrock underneath. As a consequence, the glacial deposits will hinder the weathering processes of the underlying local bedrock. In this study, we test this hypothesis by imaging the weathered layer of a previously glaciated terrain in the Medicine Bow Mountains, Wyoming using full-3D seismic ambient-noise tomography. To the best of our knowledge, our study provides the first full-3D seismic velocity model of the Critical Zone structure under a previously glaciated landscape. Our 3D seismic velocity model reveals that the saprolite weathered from local bedrock is thinner where the overlying glacial deposit layer is thicker. This anti-correlation suggests that the glacial deposits may locally protect the underlying bedrock from chemical weathering by depleting reactive chemicals in the meteoric water and (partially) saturate the meteoric water with weathering products. Our study may provide a potential counter mechanism against glaciation-induced acceleration of chemical weathering of the continents, which regulates atmospheric concentration of carbon dioxide and the global climate. © 2020 Elsevier B.V.
关键词	ambient-noise tomography chemical weathering critical zone full-3D tomography glacial subalpine watershed
英文关键词	Carbon dioxide; Carbon dioxide process; Deposits; Erosion; Geochemistry; Glacial geology; Indicators (chemical); Sediments; Seismic waves; Seismology; Ambient noise tomographies; Atmospheric concentration; Chemical weathering; Chemical weathering process; Induced accelerations; Reactive chemicals; Seismic velocity models; Weathering process; Weathering; bedrock; glacial deposit; seismic noise; seismic tomography; seismicity; snow; subalpine environment; terrain; watershed; weathering; Medicine Bow Mountains; Rocky Mountains; United States; Wyoming
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202958
作者单位	Department of Geology and Geophysics, University of Wyoming, United States; Department of Earth Sciences, National Cheng-Kung University, Taiwan; National Center for Supercomputing ApplicationsIL, United States; Earth and Environmental Systems Institute, Pennsylvania State University, United States
推荐引用方式 GB/T 7714	Wang W.,Chen P.,Dueker K.,et al. Seismic evidence of glacial deposits inhibiting weathering of local bedrock at a snow-dominated subalpine watershed[J],2020,549.
APA	Wang W.,Chen P.,Dueker K.,Lee E.-J.,Mu D.,&Keifer I..(2020).Seismic evidence of glacial deposits inhibiting weathering of local bedrock at a snow-dominated subalpine watershed.Earth and Planetary Science Letters,549.
MLA	Wang W.,et al."Seismic evidence of glacial deposits inhibiting weathering of local bedrock at a snow-dominated subalpine watershed".Earth and Planetary Science Letters 549(2020).