Volcanic Rocks of the Lake-Country

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...

Petrology of rocks in the Karik area, east of Meiduk mine of volcanic

Around The Karik village, east of Meiduk mine, Eocene volcanic rocks (andesitic basalt, andesite, dacite and rhyolite) and pyroclastic rocks (agglomerate and tuff) are exposed. These rocks are cut by several andesitic dikes. The major textures in the volcanic rocks are porphyritic and flow textures. The minerals such as plagioclase, alkali feldspar, quartz, pyroxene, amphibole, biotite and opaq...

Groundwater in Sedimentary, Metamorphic and Volcanic Rocks

Petrology and Geochemistry of the Eocene Volcanic Rocks in the West of Sechangi, Lut Block

The Eocene volcanic rocks exposed in the NW Sechangi area of Lut block, include pyroclastic deposits and lavas. These volcanic rocks are basalt, basaltic andesite, andesite, andesite-trachyandesite, trachydacite, dacite and rhyolite-ignimbrite in composition. Based on our field observations, the volcanic rocks erupted in four stages in the aquous to subaerial environments. The volcanic rocks ar...

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...