Gökçeada’nin (Çanakkale) Jeoloji̇si̇

Abstract

The geology and especially the magmatic rocks of Gökçeada, which is the biggest island of Turkey and located at 20 km's west of Biga Peninsula, constitute the subject of this study. Late Ediacaran/Early Paleozoic aged Çamlıca metamorphics which crop out with a tectonic uplift in a narrow area in northwest of Gökçeada are the oldest rocks of the island. Early Eocene aged Karaağaç Formation which is formed by submarine fan deposits unconformably overlies Çamlıca metamorphics. As for the Dağiçitepe volcanic member which is formed by rhyolitic lavas, tuff and tuffites emplaced into Karaağaç Formation cutting Çamlıca metamorphics is the oldest volcanic unit of the study area. On Karaağaç Formation, Koyunbaba Formation has unconformably been deposited which consists of Middle Eocene shallow marine sediments. Then it has conformably been overlain by Soğucak Formation which consists of SE-NW extending reefal limestone. Middle-Upper Eocene aged Ceylan Formation which conformably overlies the Soğucak Formation and the early Oligocene aged Mezardere Formation which conformably overlies Ceylan Formation have been deposited due to turbiditic currents in deep marine environment. Late Eocene(?)-Oligocene aged subvolcanics which cut Mesozoic and Eocene units and emplaced into Eocene aged sedimentary units in the form of crypto dome and dome form the recent rigid topography of the study area and are the second magmatic phase called the "Gökçeada Domes". Diorite-monzonites porphyry which crystallized in lower zones of subvolcanics on the other hand constitutes Mutludere intrusion. In eastern and southern parts of Gökçeada, Late Oligocene Gökçeada ignimbrites are located which are observed in the form of pumice flows on Mezardere Formation. These ignimbrites are then overlain by Early Miocene aged Kesmekaya volcanics which are formed by blocky ash flows. Middle Miocene aged Eşelek volcanics consisting of lava and pyroclastics with composition basaltic andesite and andesite are observed on a large area in east of Gökçeada. Upper Miocene aged Çanakkale Formation which is generally formed by the intercalation of poor consolidated conglomerate, sandstone, siltstone and marl crops out in narrow regions at east, southeast and south of Gökçeada. Quaternary alluvial deposits and debris composed of loose, unconsolidated sand, silt and other sediments unconformably overlie all previous units and complete the succession. Main tectonic structures of Gökçeada are formed by right lateral oblique faults which developed in Neo-tectonic period.

Biodiversity of freshwater macroinvertebrates on Gökçeada Island (North Aegean Sea, Turkey)

“…Considering all taxonomic studies on freshwater macroinvertebrates on the Aegean Islands, Gökçeada Island was found to occupy a prominent place among them in terms of macroinvertebrate diversity. It was hypothesized that habitat diversity (ponds, reservoirs, streams, and springs), geographical location and relief (Sarı et al 2015) were the main driving factors that increase the aquatic biodiversity of Gökçeada.…”