AshEse Journal of Engineering
Vol. 2(1), pp. 022-065, January, 2016
© 2016 AshEse Visionary Limited
Full Length Research
Zhao Bin* and Zhao Jin-song
Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangdong Province, Guangzhou, 510640, China.
Skarns hosting fluid inclusions including melt inclusions, fluid-melt inclusions and vapor-liquid inclusions were found in skarn minerals from 29 main Fe, (Cu-Fe), (Au) and Au(Cu) Mo and Mo-Cu skarn deposits of China and 7 skarn deposits from the five Western countries. The fluid inclusions are many and varied in shape. Their sizes are commonly (10-46) × (6-15) µm2. They mainly consist of crystallized silicate phases such as garnet or pyroxene then calcite, hematite, magnetite, rutile, gypsum, anhydrite and/or water, together with other vapor phases. Results of Laser Raman spectrum analyses, microthermometric studies of the fluid inclusions, analyses of Sr, Nd, C-H-O isotopic compositions for skarns containing fluid inclusions and simulated experiments of magmatic skarns at high temperatures and high pressures are presented in this paper. An assimilation model of the formation mechanism of magmatic skarns has been advanced in this way: aliuminosilicate magmas intruded into limestone or marble first, then assimilated them to form high-T (P)-modified silicate melts, generating magmatic skarns. Based on the preceding data, we have reached some important conclusions: skarns studied in this paper are of magmatic genesis, rather than contact–metasomatic or metamophic origin. They are large in size and are wide in spatial distribution. Our conclusions are the same as that reached by Zhao Bin et al. in 2003 for study on characteristics of melt inclusions in skarn minerals from Fe. Cu(Au) and Au(Cu) ore deposits in the region from Daye to Jiujiang
Key words: Skarns, inclusions, minerals, analyses.