tertiary andesitic basalts of the sirjan area, urmieh-dokhtar magmatic arc, iran, contain plagioclase phenocrysts enclosed in a matrix of amphibole, clinopyroxene and rare olivine crystals. textural and compositional evidence suggests two significantly different types of plagioclase phenocrysts occur in the andesitic basalts. the most common type of plagioclase phenocrysts have zoning patterns ...

In the southeast of bam, there is a collection of volcanic rocks with andesite, basalt and trachy andesite composition. The texture of these rocks are often porphyritic with microlithic, porphyric cavity, and sometimes glomerulophorphuri, sore throat trachytic. Main minerals include Olivine, Clinopyroxene, Plagioclase and secondary minerals including opaque minerals, Iodenzyte, secondary Biotit...

Tertiary andesitic basalts of the Sirjan area, Urmieh-Dokhtar Magmatic Arc, Iran, contain plagioclase phenocrysts enclosed in a matrix of amphibole, clinopyroxene and rare olivine crystals. Textural and compositional evidence suggests two significantly different types of plagioclase phenocrysts occur in the andesitic basalts. The most common type of plagioclase phenocrysts have zoning patterns ...

Abstract Pandan volcano is one of the dormant Quaternary volcanoes in East Java characterized by several volcanic centers which extend to northern part. This study aimed identify rocks and intrusions Jari - Krondonan area, Bojonegoro as well determine their petrology mineralogical characteristics. Geological observation was conducted obtain primary data collect samples. Thin section samples pre...

The Eocene-Oligocene Sarbisheh volcanic complex is a part of the Lut-Sistan Zone that outcrops in eastern Iran. In the east of this complex, three groups of volcanic rocks (i.e., andesite, dacite, and rhyolite) exist. Plagioclase as the main mineral of these rocks is found with varying micro-textures. Based on a changing trend in the concentration of anorthite, the developed micro-textures (coa...

late miocene–pliocene calc-alkaline volcanic rocks are exposed southeast of isfahan in the urumieh-dokhtar magmatic belt. volcanic rocks consist of lava flows and domes, chiefly basaltic andesites, andesites and dacites. minerals in the volcanic rocks exhibit degrees of disequilibrium features. plagioclase as dominant mineral in these rocks generally displays reverse and oscillatory zoning; sie...