暴露岩石表层中的宇生核素的浓度,是产生速率、衰变常数及侵蚀速率的函数。根据该原理,在宇生核素形成速率为已知的条件下,建立宇生核素浓度与时间及侵蚀速率的函数关系,根据该模式可对岩面的暴露时间及侵蚀速率进行计算,这使得该测年技术在地貌学与第四纪研究中有着极大的运用前景。在众多的宇生核素中,取自于石英的26Al和10Be是目前该领域中运用最广泛、最成熟的宇生核素。
Because of cosmogenic isotopes production, the concentration of cosmogenic isotope in surface layer of the exposed rocks accumulates more and more, and at same time, it becomes less and less with isotope’s radiation and surface’s erosion. With this principle, under the condition of cosmogenic isotopes production rate being well known, the function between the concentrations of cosmogenic isotopes and time and erosion can be calculated. Using this model, we can calculate the exposed ages and erosion rate of the surface. This makes the dating technique be very useful and have a good provision in the study of Geomorphology and Quaternary. In cosmogenic isotopes, 26Al and 10Be deriving from quartz are used most widely and maturely in this field.
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