VII.—Mesozoic Volcanic Rocks of British Columbia and Chile. Relation of Volcanic and Metamorphic Rocks

Groundwater in Sedimentary, Metamorphic and Volcanic Rocks

Generalized Titanomagnetite in Hawaiian Volcanic Rocks'

A ferromagnetic oxide mineral with spinel structure was separated from Hawaiian volcanic rocks ranging from basalt to trachyte . The chemical compositions of all the specimens have been arranged on an oxygen reaction line, and can safely be interpreted as the result of a process of either oxidation or reduction of material with composition on or near this line. In the trachyte the mineral was f...

Mineral chemistry and thermobarometry of Eocene Alkaline volcanic rocks in the Southwest of Germi, NW Iran

Petrography and chemistry of minerals showing that Eocene alkaline volcanic rocks in southwestern of Germi (Talesh zone, NW Iran) mostly have basaltic composition. Mineralogically these rocks are composed of diopsidic clinopyroxene and labradoritic plagioclase phenocrysts. The microlithic and glassy groundmass composed of sanidine, clinopyroxene, biotite, pargasitic amphibole and magnetite asso...

Petrogenesis of alkalic and calcalkalic volcanic rocks of Mormon Mountain Volcanic Field, Arizona

The Cenozoic Mormon Mountain Volcanic Field (MMVF) of northern Arizona is situated in the transition zone between the Basin and Range and the Colorado Plateau. It is composed of alkalic to sub-alkalic basalts and calcalkalic andesites, dacites, and rhyodacites. Despite their spatial and temporal association, the basalts and the calcalkalic suite do not seem to be co-genetic. The petrogenesis of...

Chemistry of mafic minerals and thermobarometry of Bazman Quaternary volcanic rocks

  Abstract 1-Introduction Bazman volcano is located on Chgay - Makran magmatic arc. This magmatic arc with east-west trend is 500 km long and 150 km wide and extends from southeastern Iran to southwestern Pakistan. Early evolution of the Makran zone from the upper Oligocene to the upper Miocene is characterized by turbidite sediments deposited on the oceanic crust. There are several quaternary...