四川会东大梁子铅锌矿床锗富集于方铅矿中的新证据

NEW EVIDENCE FOR THE ENRICHMENT OF GERMANIUM IN GALENA OF THE HUIDONG DALIANGZI LARGE-SCALE Pb-Zn DEPOSIT,SICHUAN PROVINCE,CHINA

由于锗的离子半径与锌的离子半径相近,一般认为铅锌矿床中的锗主要与锌发生类质同像赋存于闪锌矿中,但也有证据表明,铅锌矿床中的锗也可富集于方铅矿中。对四川会东大梁子大型铅锌矿床进行了电子探针研究,锗特征X射线面扫描结果表明:该铅锌矿床原生矿石中方铅矿中的锗含量明显高于闪锌矿中的锗含量,且锗均匀分布在方铅矿中,没有出现明显高于本底的富集点,初步推测锗在方铅矿中以类质同像的形式存在。该结果为铅锌矿床锗富集于方铅矿中提供了新证据。

Generally speaking, most germanium is of isomorphous substitution of zinc in sphalerite in Pb-Zn deposits, but also has evidence to indicate that in some Pb-Zn deposits germanium also may be enriched in galena. In the processes of electron probe observation, characteristic X-ray face scanning and analyzing the primary ore in the Huidong Daliangzi large-scale Pb-Zn deposit, Sichuan Province, China, the results indicated the concentrations of germanium in galena are higher than those of sphalerite, and also the germanium is uniformly distributed in the galena, and shows no appearent concentration spots obviously higher than the background value. It is primarily considered that the germanium is of isomorphous substitution in the galena. This result provides new evidence for the enrichment of germanium in primary galena in some Pb-Zn deposits. The mechanism of germanium enrichment in primary galena needs further studies.