Bozaniç (Sarıcakaya-Mihalgazi, Eskişehir) volkaniti lavlarının petrografik özellikleri

Abstract

Bu çalışmada, Bozaniç (Sarıcakaya-Mihalgazi, Eskişehir) volkanitine ait lavların petrografik özellikleri araştırılmıştır. Buna göre, petrografik özellikleri belirleyebilmek için altere olmamış kayaçlardan derlenen örneklerden ince kesitler yapılarak polarizan mikroskopta incelenmiştir. Elde edilen veriler, kayaçların genel olarak hipokristalen porfirik, mikrolitik porfirik, trakitik, glomeroporfirik ve hipohyalin porfirik dokular gösterdiklerini ve çoğunlukla volkanik camdan ibaret bir hamur içerdiklerini ortaya koymaktadır. Kayaçlarda hâkim mineral parajenezi plajiyoklaz + hornblend ± klinopiroksen ± opak mineraller ± biyotit ± sanidin ± kalsit ± klorit ± kalsedon şeklindedir. Kayaçlar, modal mineralojik bileşimlerine göre yapılan adlandırmalara göre, çoğunlukla andezit; nadiren de traki-andezit, bazaltik andezit veya latit bileşimindedirler

Keywords

• Bozaniç, volkanit, lav, petrografi

Petrographic characteristics of lavas of Bozaniç (SarıcakayaMihalgazi, Eskişehir) volcanite

Abstract

In this study, petrographic characteristics of lavas of Bozaniç (Sarıcakaya-Mihalgazi, Eskişehir) volcanite were studied. Accordingly, in order to determine the petrographic characteristics, thin sections were prepared from the samples compiled from the unaltered rocks and those were investigated under the polarized microscope. Obtained data exhibit that the rocks reveal the textures of hypocrystalline porphyric, microlitic porphyric, trachytic, glomeroporphyric, and hypohyaline porphyric and they usually contain the matrix consisting of volcanic glass. Dominant mineral paragenesis is plagioclase + hornblende ± clinopyroxene ± opaque minerals ± biotite ± sanidine ± calcite ± chlorite ± chalcedon. The rocks are in composition mostly of andesite; rarely of trachy-andesite, basaltic andesite or latite according to the naming by their modal mineralogical compositions

Keywords

• Bozaniç, volcanite, lava, petrography

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