摘要
本文介绍了Sm-Nd法的制样特点与技术改进。我们研究配制的Nd^+发射剂及新编计算机程序,实现了高产额Nd^+的单铼带同位素分析。本方法已应用了研究对中国大陆地幔的化学不均匀性,花岗岩的成因和年龄测定,并将对年龄数据及示踪应用方面取得的若干新成果进行了简要讨论。
In sample preparation four spikes (149Sm, 116Nd, 84Sr, 87Rb) were put into the sample.After dissolution and separation, the solutions of Sm, Nd, Sr and Rb could be obtained, respectively. The isotopic compositions and concentrations were measured in one mass spec-trometric analysis using the computer program edited by us. In order to enhance the sensiti-vity of Nd+ analysis with a single filament, an emission reagent was developed.The measured value for La Jolla Nd standard is 145Nd/144Nd = 0.511845± 0.000006(2a) which is very close to that obtained by Lugmair. NBS987 was measured with 87Sr/86Sr = 0.710221 ±0.000003.The developed Sm-Nd technique has been used to study the origin of granites and the che-mical heterogenity of subcontinental mantle in eastern and southwestern China.Several Sm-Nd isochrons for the Archean restites in tonalites from Shanxi Province and the Precambrian metavolcanics and ultramafic rocks from Yunnan and Shandong provinces were also measured, respectively.
出处
《地球化学》
CAS
CSCD
北大核心
1989年第1期36-42,共7页
Geochimica
