摘要
同步辐射X射线荧光(SRXRF)微束分析是一种无损而又具有较低检测限的技术,但在地学上的应用较少。本文尝试用SRXRF技术对川西伟晶岩型矿床——甲基卡稀有金属矿床和丹巴白云母矿床进行对比性研究。同一矿床的同类样品的SRXRF图谱形态相近,说明测试状态稳定和测试结果可信。在甲基卡矿区,相对于石英脉,锂辉石矿脉石英中的包裹体检测出较多的Fe、Mn、Co元素,并出现Ti、Rb、Ga、Zn等元素。在丹巴矿区,相对于李家工地白云母矿脉,春牛场伟晶岩检测出S及Zn,Fe的含量也较高。相对于丹巴矿床,甲基卡矿床中的包裹体相对富集金属元素,特别是Ga、Rb等。这些测试结果显示出甲基卡稀有金属矿床和丹巴白云母矿床流体组成的差异,以及矿化和非矿化伟晶岩流体的差异;说明了SRXRF是一种有效的流体包裹体测试手段,但还需要降低SRXRF探针聚焦光束光斑的大小,提高测试数据的定量化精度。
SRXRF is an analysis technology with non-damage and low detection limit. Geologically, this technology is little applied. In this paper, SRXRF is used to detect the composition of fluid inclusions in pegmatite type deposits such as the Jiajika rare metal deposit and Danba muscovite deposit in western Sichuan Province. The SRXRF spectrums of the same type dyke in the same deposit are similar, which show the experiment is in a stable state and the spectrums are reliable. In the Jiajika deposit, the spectrum peak values of Fe, Mn, Co in the fluid inclusions of No. 134 dyke are higher than those of quartz dyke. The peaks of Ti, Rb, Ga, Zn present in the fluid inclusions of No. 134 spodumene dyke, but not in quartz dyke. In the Danba deposit, the spectrum peaks of S, Zn present in the fluid inclusions of the Chunniuchang pegmatite, but not in the Lijiadongdi pegmatite. The peak value of Fe in the fluid inclusions of the Chunniuchang pegmatite is higher than that of the Lijiagongdi pegmatite. Comparing with the Danba deposit, the Jiajika deposit is rich in metal elements, especially Ga and Rb. In conclusion, the experi- ment shows that the compositions of mineralizing fluids in the Jiajika and Danba deposit are different, and the com- positions of mineralizing and non-mineralizing fluids are different, too. On the other hand, this study shows that SRXRF is an effective method to detect the compositions of fluid inclusion, and it is necessary to decrease the radius of SRXRF facula, in order to increase the precision of SRXRF.
出处
《大地构造与成矿学》
EI
CAS
CSCD
北大核心
2008年第3期332-337,共6页
Geotectonica et Metallogenia
基金
国家自然科学基金项目(40702014,40543033)
中央级公益性科研院所基本科研业务费专项资金(K2007-1-6)
中国地质调查局国土资源大调查项目(编号1212010733803,1212010634002)资助
关键词
SRXRF
伟晶岩
甲基卡
丹巴
SRXRF
pegmatite
Jiajika
Danba
western Sichuan
