摘要
岩浆房持续的时间尺度对认识岩浆房的稳定性、评估活动火山的活跃程度具有重要意义。扩散计时法将具有元素浓度梯度的矿物作为计时器,由于矿物中的元素扩散再平衡过程符合菲克第二定律,与时间有关,从而可以限定岩浆作用过程的时间尺度,进而指示岩浆房持续的时间。该方法目前已广泛应用于不同火山岩矿物,如橄榄石和辉石Fe-Mg元素扩散、斜长石Mg元素扩散、石英Ti元素扩散以及锆石Li元素扩散等,可以记录持续仅数小时至几百万年的岩浆过程。未来,随着原位分析测试技术的不断发展、与岩浆作用有关的扩散系数的可用性和精度的增加、扩散模型的完善将极大地推动矿物内元素扩散年代学的发展。
The duration of a magma chamber is of great significance for understanding the stability of the magma chamber and evaluating the active degree of active volcanoes.The element diffusion chronometry uses minerals with element concentration gradients as timers.Since the diffusion and reequilibrium process of elements in minerals conform to Fick’s second law which is related to time,the time scale of the magmatic process can be defined to indicate the duration of a magma chamber.This method has been widely used in different minerals in volcanic rocks,such as Fe-Mg element diffusion in olivine and pyroxene,Mg element diffusion in plagioclase,Ti element diffusion in quartz and Li element diffusion in zircon,etc.These methods can record magma processes for only a few hours to millions of years.In the future,with the continuous development of in situ analysis and testing technology,the increase in the availability and accuracy of diffusion coefficients related to magmatism,and the improvement of the diffusion model,the development of element diffusion chronology in minerals will be greatly promoted.
作者
陈祖兴
曾志刚
王晓媛
殷学博
陈帅
张玉祥
Chen Zuxing;Zeng Zhigang;Wang Xiaoyuan;Yin Xuebo;Chen Shuai;Zhang Yuxiang(Key Laboratory of Marine Geology and Environment,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China;University of Chinese Academy of Sciences,Beijing 100049,China;Laboratory for Marine Mineral Resources,Qingdao National Laboratory for Marine Science and Technology,Qingdao 266061,China)
出处
《地球科学进展》
CAS
CSCD
北大核心
2020年第12期1232-1242,共11页
Advances in Earth Science
基金
国家自然科学基金项目“西太平洋俯冲体系中岩浆活动及其对热液物质供给的制约”(编号:91958213)
中国科学院国际合作局对外合作重点项目“冲绳海槽热液活动成矿机理及其沉积效应”(编号:133137KYSB20170003)资助。
关键词
成分环带
扩散系数
岩浆房持续时间
Composition zoning
Diffusion coefficient
Duration of magma chamber
