Türkiye Jeoloji Bülteni

Öz

The Çamlıca metamorphic association located on the western part of the Biga Peninsula covers an area of 2 about 196 km . The rock units of the Çamlıca metamorphic association are separated into three units, which are described as formations based on the partly determined internal structure, on contact relationships, and on a mappable unit. These formations from bottom to top are, respectively: the Andıktaşı formation which comprises metalava, metatuff, and metapelite and that appears brown, green, and yellowish green-coloured in the field; the Dedetepe formation which is mainly made up of quartz-muscovite schist, garnet-muscovite schist, garnet-albitechlorite schist and albite-chlorite-epidote schist, black marble, calc-schist, amphibolite and eclogite. On the top, the Salihler formation is composed mainly of phyllite, calc schist and white marble intercalations. The Denizgören ophiolite, including serpentinised peridotite, tectonically overlies the Çamlıca metamorphic association. Petrographical investigations, using index minerals of albite - garnet - epidote - chlorite observed in three different formations, indicate that the Çamlıca metamorphic association was subjected to the greenschist - facies metamorphism. An early eclogite - facies mineral assemblage of garnet + omphacite + glaucophane + amphibole has been determined. These mineral associations were subjected to amphibolite-facies metamorphism and finally to retrograded greenschist-facies metamorphism. The Çamlıca metamorphic association is, then, probably an equivalent of the Iznik metamorphics located in the Sakarya Zone in terms of lithostratigraphy, stratigraphy and metamorphic characteristics.