新疆阿尔泰可可托海3号伟晶岩脉绿柱石流体包裹体SRXRF研究

尝试利用北京同步辐射装置(BSRF)实验条件所产生的4W1B束线同步辐射X射线荧光微探针,对新疆可可托海3号伟晶岩绿柱石中的单个流体包裹体进行原位无损成分分析,改进了实验中显微镜照明装置而获得较好的视觉观察效果,使探测目标选取更加快速、准确,测试结果更加可靠。测试及研究结果表明,新疆可可托海3号伟晶岩脉绿柱石中多数流体具有较高的Zn、Sn、As以及REE元素含量,反映了其内生岩浆作用特征及流体的壳源特点;蛛网图显示微量元素含量特征与中国中东部地壳相似,进一步提示流体可能源自地壳。但由于测试中束斑面积较大(50μm×50μm),影响了测试精度,今后可通过缩小光斑、提高射线能量及能量分辨率来进一步提高测试精度及可靠性。

SRXRF study of fluid inclusions in Beryl from the Kektokay No.3 pegmatite vein, Altay, Xinjiang

This paper made a tentative in-situ nondestructive study of components of single fluid inclusions from No.3 granitic pegmatite vein in Altay of Xinjiang by SRXRF which was generated by beamline 4W1B of Beijing Synchrotron Radiation Facility(BSRF).The authors have improved micro-vidio lightning facility by which better,faster and more precise visual effects could be obtained,and the test results are more reliable.Studies show that most fluid inclusions of No.3 granitic pegmatite vein have relatively high concentrations of Zn,Sn,As and REE which may be the characteristics of endogenous magmatism and crustal source.Spider diagram shows the similarity between Kektokay No.3 granitic pegmatite vein and the crust in middle and east China in the concentration style of trace elements,suggesting that the source of the fluid might have been derived from the crust.The relatively large X-ray spot(50 μm×50 μm) might have affected the accuracy of the test,but it can be avoided and the test accuracy can be improved by shrinking the light spot,raising the energy of the beam and enhancing energy resolution of the facility.