High-Phosphorous Lithium–Fluorine Granites of Eastern Yakutia (Verkhoyansk–Kolyma Orogenic Region)

Resumo

The paper considers the petrographic composition and petro- and geochemical features of high-phosphorous lithium–fluorine granites from the Arga–Ynnakh–Khaya and Burgali ore–magmatic clusters in eastern Yakutia. Granitoids of three successively formed petrotypes are recognized here: amphibole–biotite granodiorites and andesine granites close to I-type granitoids; S-type two-mica cordierite granites; and plumasite lithium–fluorine granites. The latter are characterized by extremely high Li, Cs, F, and P contents; they are ascribed to ultra-rare-metal rocks and are not complementary to the preceding granitoids. They are assumed to be the derivatives of independent melts obtained from a lower crustal protolith that was reworked by ore- and volatile-rich fluids related to upwelling subalkaline or alkaline basaltic melts.