Field, Mineralogical and Petrographic Features of the Micro-Vesiculated Mafic Enclaves in the Miocene Lava Around Sağlik and Yatağan Area, Western Konya/Türkiye

Abstract

Various Mafic Microcrystalline Enclaves (MMEs) occur in variable sizes (from a few cm to a few meters) and shapes (ellipse/rounded-angular) with well-developed chilled margin in lava dome complex as part of the subduction-related Neogene Erenlerdagi volcanic activity at the west of Konya. In/around MME, some angular-rounded space developed, possibly due to shrinking after magma degassing, and sometimes filled by calcite. Petrographical and modal image analysis shows that the micro-vesiculated MME contains plagioclase (10-84 %, 0.09-3.1 mm), amphibole (10-25%, 0.16- 1.64 mm), clinopyroxene (7-20%, 0.37-0.77 mm), quartz (0-10%, 0.2-0.6 mm), biotite (0-5%, 0.81-1.63 mm), epidote (0-10%, 0.1-0.7 mm), piemontite (0-9%, 0.17-0.55mm), allanite (0-9%, 0.17-0.55 mm) and opaque iron ore (4-54%, 0.03- 0.67 mm) as major constituents with accessory apatite and zircon in a diktytaxitic-like and hypidiomorph granular texture. The MME also contain older and smaller enclaves (MMEs), which are composed of plagioclase (20-82%), brownish amphibole (9-25%), clinopyroxene (5%), quartz (3-10%), epidote (10-25%), and opaque iron ore (10-35%) in a diktytaxitic-like texture. MMEs are suggested to be formed by syn-eruptive mafic (basaltic?) magma underplating of a dacitic magma reservoir at the lower crust, possibly triggering the eruptions of silicic domes by an overpressure build-up. © 2024, Gumushane University. All rights reserved.