摘要
简要介绍了土壤和风化壳剖面中宇成核素的收支情况和累积， 并通过几个实例介绍了国外和境外一些土壤和风化壳的宇成核素研究情况： 土壤和风化壳的年龄和表面侵蚀速率， 坡地土壤的生成速率和蠕滑速率， 土壤面的地貌演化过程， 以及一些土壤侵蚀事件研究。土壤和风化壳的宇成核素研究多数都要在一些假设条件下进行， 因而受到很大限制。不过尽管如此， 仍不妨碍进行土壤和风化壳宇成核素研究的尝试性工作。只是应该注意， 进行这类工作时首先要对研究地区的地质过程有清楚了解， 并尽可能与相关资料进行对比， 以期对结果给予合理的解释。
The balance and accumulation of cosmogenic nuclides in soil and weathering profile are described briefly in this paper. Several instances are introduced to depict the contemporary advance on the application of cosmogenic nuclides to the researches on soil and weathering profiles. Cosmogenic nuclides can be used to estimate the minimum age of soil and weathering profile development, to estimate the surface denudation rate, to calculate the soil creep rate and bedrock-to-soil conversion rate on a slope, and even to track and investigate the evolution of the surface of a soil and weathering profile. However, all these applications of cosmogenic nuclides are strictly constrained. They are processed under many hypotheses. For example, in all these applications it is assumed that the production rates of cosmogenic nuclides (for 10 Be in soil and weathering profile, it is the atmospheric deposition rate) don′t change in the period concerned. In fact, the production rates of cosmogenic nuclides are affected by climate and geomagnetic field and usually have some variations. This contributes greatly to the uncertainty of the research result, and limits the use of cosmogenic nuclides in the research on soil and weathering profile.Despite the shortages, cosmogenic nuclides as a new kind of tracer should be encouraged to be used in the study of soil and weathering profile. It is believed that the development of AMS in our country will promote this kind of research in our country. However, when cosmogenic nuclides are used, as more information as possible about the geological process of the research area should be used in order to explain the result as reasonable as possible.
出处
《热带地理》
北大核心
1999年第4期365-370,共6页
Tropical Geography
基金
国家自然科学基金
广东省自然科学基金
关键词
土壤
风化壳
宇成核素
土壤侵蚀
Soil
Weathering Profile
Cosmogenic Nuclides
Instance
