0 引言
1 氦源岩
岩石类型 | U/(10-6) | Th/(10-6) |
---|---|---|
花岗岩 | 3.0 | 13.0 |
页岩 | 3.7 | 12.0 |
砂岩 | 0.45 | 1.7 |
灰岩 | 2.2 | 1.7 |
富有机质页岩(热页岩) | 50.0 | 12.0 |
铝土矿 | 25.0 | 56.0 |
李平(1987-),男,江苏南京人,博士,副研究员,主要从事环境地球化学研究. E-mail:liping@lzb.ac.cn. |
收稿日期: 2022-10-26
修回日期: 2023-02-05
网络出版日期: 2023-04-18
Research progress on diffusion process and controlling factors of helium in minerals
Received date: 2022-10-26
Revised date: 2023-02-05
Online published: 2023-04-18
Supported by
The Project of Stable Support for Youth Team in Basic Research Field, CAS(YSBR-017)
the National Key Research and Development Projects of the Ministry of Science and Technology of China(2021YFA0719003)
研究氦在矿物中的初次运移过程是认识氦气成藏机制的基础。研究对氦的产生、扩散和释放过程及主要控制因素进行了系统综述。放射性元素U和Th发生α衰变后,产生的氦在晶格中可发生间隙迁移、与缺陷位复合,并通过自捕陷、迁移合并或热融合方式形成氦泡并长大,氦泡贯通后促进氦释放。氦也可通过α衰变形成的裂变径迹释放。氦源岩组成与晶体结构不同时,矿物对氦的封存能力存在显著差异;高温有利于氦的扩散与氦泡的长大,促进氦的释放;压裂及矿物转化过程也可引起氦的迅速释放。阐明氦初次运移的微观过程与主控因素,可为系统认识氦气的来源、运移聚集等成藏过程,以及氦气成藏理论的建立提供重要的理论基础。
李平 , 马向贤 , 张明震 , 王威 , 丁哲 , 宋佳钰 , 鄂正阳 , 梁建军 , 彭楠 , 罗双江 , 范桥辉 . 矿物中氦的扩散过程及控制因素研究进展[J]. 天然气地球科学, 2023 , 34(4) : 697 -706 . DOI: 10.11764/j.issn.1672-1926.2023.02.001
The knowledge of the primary migration of helium is key for understanding the accumulation process of helium. In this review, the diffusion and release of helium in minerals and the controlling factors are systematically reviewed. Helium generated by the α decay of radioactive U and Th would undergo interstitial migration, combines with the vacancies, and accumulates to helium bubbles, which promotes the release of helium. Helium can also be released through fission tracks induced by α decays. The difference in the composition and crystal structure of the minerals leads to different ability for storing helium. High temperature facilitates the diffusion of helium and the growth of helium bubbles, benefiting helium release. Fracturing and the transformation of minerals can also cause the rapid release of helium. Elucidating the processes of the primary migration of helium and the controlling factors should be of significant importance for understanding the source, migration and accumulation of helium reservoir.
岩石类型 | U/(10-6) | Th/(10-6) |
---|---|---|
花岗岩 | 3.0 | 13.0 |
页岩 | 3.7 | 12.0 |
砂岩 | 0.45 | 1.7 |
灰岩 | 2.2 | 1.7 |
富有机质页岩(热页岩) | 50.0 | 12.0 |
铝土矿 | 25.0 | 56.0 |
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