水土保持通报2011，Vol.31Issue(3)：103-107,5.
利用宇宙成因核素^10Be,^26Al估算流域侵蚀速率的原理与应用
Calculating Erosion Rate of Drainage Basin by ~（10）Be and ~（26）Al Measurements：Theory and Application
摘要
Abstract
Erosion is an exogenic agent of landscape evolution.Quantitatively calculation of erosion rates and the reveal of the climate-erosion-tectonics feedback system are important research subjects in Geosciences.The average rates of exhumation can be obtained from thermochronology on time scale of millions of years,and erosion rates from hydrological measurement on time scale of tens of years.As a supplement,erosion rates on time scale of ten thousands of years can be calculated by measuring cosmogenic nuclide（10Be and 26Al） from river terrace deposits or basin sediments.Cosmogenic nuclides were primarily generated by reaction of quartz grains exposed near earth surface by galactic cosmic radiation,which were then suddenly and deeply buried to shield off cosmicrays after exposure of short time on the ground surface.Generally,the quartz grains have a short time exposure and low cosmogenic nuclide concentration.In addition,the cosmogenic nuclide decreases over time after burial.Quantitatively calculation of erosion rates from 10Be and 26Al is a concept based on dating river terrace deposits or basin sediments by determination of 10Be concentration.Combining 10Be and 26Al measurements,surface exposure ages or erosion rates can then be calculated.The method is precise,easily accessible and widely applicable.It can be used for longer time scales and broader spatial scales,and it is a new method important to landscape evolution research from Quaternary to Holocene.关键词
宇宙成因核素/^10Be,^26Al/侵蚀速率/流域Key words
cosmogenic nuclides/10Be/26Al/erosion rate/drainage basin分类
天文与地球科学引用本文复制引用
胡二伢,李颍,赵志军..利用宇宙成因核素^10Be,^26Al估算流域侵蚀速率的原理与应用[J].水土保持通报,2011,31(3):103-107,5.基金项目
国家自然基金项目“玉门砾岩、酒泉砾石层的宇生核素埋藏测年及其记录的流域侵蚀速率研究” （）
