NEODYMIUM AND STRONTIUM ISOTOPE GEOCHEMISTRY AND SOURCE OF MINERALIZING COMPONENTS OF FLUORITE DEPOSITS IN THE WUYI-DONGYANG AREA, ZHEJIANG PROVINCE, SOUTHEAST CHINA

摘要

Zhejiang is one of the most famous fluorite provinces in the circum-Pacific belt. Over 80% of the total fluorite reserves of Zhejiang occur in the uplift belt of Precambrian fold basement of middle Zhejiang. Most of fluorite deposits in middle Zhejiang are distributed in the Wuyi-Dongyang area, where more than 30 large- and medium-sized deposits that have high grades (avg. approx. 70% CaF_2) are known in an area of about 3000 km~2. In this paper, based on strontium (39 samples) and neodymium (25 samples) isotopic compositions of fluorites and related rocks obtained from 9 deposits, as well as a ratio-type equation of the three-member mixing model of isotopes and ore-forming elements, we further provide some quantitative results on the source of the ore-forming fluorite.