Age and Composition of Columbite-Tantalite Group Minerals in the Spodumene Pegmatite from the Chakabeishan Deposit, Northern Tibetan Plateau and Their Implications

The Chakabeishan (CKBS) deposit is the first pegmatite-type Li-Be discovered in eastern North Qaidam Tectonic Belt (NQTB) of Tibetan Plateau. correct understanding its petrogenesis and precise determination formation age are great significance for further regional prospecting discovery new economically valuable rare-metal deposits. Therefore, a systematic study texture, major-element composition, U-Pb dating columbite-tantalite group minerals (CGMs) spodumene pegmatite dyke from CKBS was undertaken. Three types CGMs were identified, including concentric oscillatory ferrocolumbite (CGMs-1), homogeneous (CGMs-2), irregular ferrotantalite (minor manganocolumbite) with abundant early replacement remnants (CGMs-3). zoning patterns chemical compositions record complex evolutionary history their host magmatic stage (CGMs-1, disequilibrium crystallization) to magmatic-hydrothermal transition (CGMs-2, equilibrium then late metasomatic (CGMs-3, replacement/re-equilibrium). results suggest that (No.15) emplaced at 230.1 ± 2.6 Ma. Subsequently, it experienced fluid metasomatism 221 5.3 Based on data published geochronological data, can be concluded dykes formed an oceanic subduction-related setting, representing metallogenic event western China. Except deposit, large number have also been NQTB, indicating NQTB may important potential belt should explored detail arouse painstaking attention.