Petrology, geochemistry and structural properties of the Ladik dike swarm, Ladik-Sarayönü, Konya

Afyon Zone forms a part of the Anatolid-Tauride platform which underwent to high pressure metamorphism during Palaeocene. The exposures of Afyon Zone to the NW of Konya comprise dykes (Ladik dyke swarm) cutting the Palaeozoic rock units or making contact with meta- volcanic and volcaniclastic sediments (Kadınhanı volcanics). The age of this unit is mostly thought to be Devonian-Lower Carbonifferous-Permien in previous studies. In this study, the tectonic meaning of the U-Pb LA-ICP-MS zircon dating is discussed. One sample (meta-tonalite) from Ladik dyke mass and one sample (meta-trachyte) from Kadınhanı volcanics were dated by LA-ICP-MS analyses. The Carboniferous melange is tectonically overlaid by the Silurian-Devonian Bozdağ meta-carbonate platform slice cut by dykes in diabase, microgabro and tonalite composition which affected by blueschists facies metamorphism. Dykes are mostly parallel to each other, from 1 to 5 m in width and a few km in length creating a set of NW-SE trending. > 60 individuals dykes exist in this cluster (4 km in width). The chemical composition of these dyke indicate that the dykes were formed from same magma by fractional crystalization. The basic dykes present similar horizontal pattern to MORB on N-MORB normalised spidergram and show Nb depletion. xx The meta-trachyandesitic lavas and associated volcaniclastic sediments take place to the SE of Kadınhanı. Geochemistry of the lava reflects a rift environment containing subduction component. U-Pb dating of zircons separated from the sample of Kadınhanı meta- trachyandesites yielded a concordia age of 229±1.3 Ma (MSWD 1.19). Zircons from the sample of Ladik dyke mass have a considerable Pb loss. So that, a Concordia age of 221±4.1 Ma (MSWD 0.9) was obtained by using the most concordia ages from the data set. The data obtained by this study indicate that both of the Ladik dyke mass and Kadınhanı meta- trachyandesites were formed by the rifting of the northern margin of Gondwana during Upper Triassic. July 2024, 129. pages.