PETROGRAPHY, GEOCHEMISTRY AND METAMORPHISM CHARACTERISTICS OF THE MIDDLE NAPPE (SUGOZU MELANGE) OBSERVED IN THE ALANYA UNIT METAMORPHITES (ALANYA, ANTALYA, TURKEY)

摘要

Study area is in the area of Alanya and Obakoy (Antalya, Turkey) in southern part of Central Taurides. The Alanya unit consists of three metamorphic nappes. The Mahmutlar group (lower nappe) is made up Cambrian and Upper (?) Permian aged mica schist, chloritoid schist, greenschist, phyllite, dolomite, quartzite and crystallized limestone. Upper Cretaceous - Paleocene settlement aged Sugozu melange (middle nappe) that unknown age of formation is made up of garnet-mica schist with greenschist, amphibolite, glaucophanite, eclogite bands-lenses and metagabro levels. The Yumrudag group (upper nappe) is made up Cambrian, Upper Permian, Lower Triassic and Middle (?) - Upper Triassic aged mica schist, greenschist, quartz schist, chloritoid schist, calc schist, crystallized limestone, phyllite and dolomite. In the middle nappe, the magmatic rocks such as eclogite, amphibolite and greenschists are basaltic in character; glaucophanites are of basaltic and and esitic/dasitic composition. These metamagmatic rocs are associated with a sub-alkaline magmatism of a subduction zone. During Late Maastrichtian, the lithologies of the middle nappe of the Alanya unit underwent eclogite and subsequently epidote - blue schist facies metamorphism in the subduction zone. Following the high pressure - low temperature (HP-LT) metamorphisms the Alanya unit underwent a progressive amphibolite facies metamorphism during the Paleocene, probably Early Paleocene. During the Late Paleocene-Early Eocene, during or following the nappe emplecemens in the Alanya unit, the whole unit underwent a retrograding metamorphism in greenschist facies.