Abstract:

Furong super-unit is a part of Qitianling granite mass which is Yanshanian complex pluton, and is mainly composed of adamellite and moyite. K₂O+Na₂O in content ranges from 7.32% to 10.01%, the average is 8.17%. In the granitic classification diagram of K₂O-Na₂O, the most samples are plotted in the area of A-type granite, but they are characterized by high TiO₂, CaO, MgO, and lower FeO^*/MgO contrasted with the typical A-type granite. The REE distribution patterns of granite are similar to each other, and show typical LREE enrichment, an obvious negative Eu anomaly pattern. The LREE distribution curves are light right deviation and the part of HREE almost smooth. For the trace elements of granite, Rb and Th are enriched strongly, Sr and Ti appear as strong depletion, and Ba, Ta, Nb, Nd, Zr and Hf also show a character of enrichment in a certain degree. Qitianling granite with high tin background content is favorable to tin mineralization in space environment and time stage, showing a good potential to tin mineralization.

Key words: Qitianling, A-type granite, geochemistry, metallogenic potential；southern Hunan, tin