The intraplate alkaline-granite magmatism essentially contributes to formation of rare-metal strategic raw materials. In the Major Sayan Fault East Mountains, rocks Zashikhinsky (Pz 3 ) massif were studied through isotope-geochemical analysis identify probable sources magma and mechanisms their evolution resulting in ore accumulations, up Nb-Ta deposits. Nd isotopic characteristics its alkaline...

Sixteen new K-Ar dates are presented from Tasmanian and Bass Basin basalts, more than doubling the previously published number. Eight volcanic regions are described, based on boundaries established on the range of the basalt types contained in each geographic region. Volcanism occurred within the span from Eocene to Miocene (47 to 13+ Ma), but mainly within the time range Middle Eocene to Early...

Hornblende occurs in some andesitic and basaltic rocks of calc-alkaline affini1y, where it is commonly associated with olivine. The texture, eruption history, and composition are interpreted to indicate that hornblende commonly forms as a product of reaction between olivine and basaltic and andesitic liquids. The natural hornblendes probably formed within the crust at temperatures between 960o ...

introduction the study area is located in the shurab area that is about 50 km southeast of qom. volcanic rocks of the shurab area have basaltic composition that is associated with salt and marl units. igneous rocks of the shurab area have not been comprehensively studied thus far. clinopyroxene composition of volcanic rocks, and especially the phenocrysts show magma chemistry and can help to id...