THE AIRBORNE MAGNETIC SIGNATURE OF GÖKOVA GULF

Yıl 2013, Cilt: 147 Sayı: 147, 169 - 177, 01.12.2013

Uğur Akın Ahmet Üçer

Öz

The gulf of Gökova, which is located in the Aegean Extensional Zone of Turkey, has been a point of interest for many investigators. This gulf takes place within the regional extensional tectonic regime in NS directions. The extension of Western Aegean in N-S directions has also formed many other grabens which are perpendicular to grabens in E-W directions. The gulf has an approximate length of 100 km’s (in EW) and 25 km’s (in NS). Datça and Bodrum peninsulas take place towards south and north of the gulf, respectively. In recent years, Full Tensor Gradiometer (FTG) potential field methods have widely been used among the gravity and magnetic methods. In the past, vertical component of the magnetic field has been measured as it had been done in the gravitational method. However; this method has turned into total area measurements (x, y and z components) in recent applications. This method was applied to the data of total aeromagnetic field. FTG method was applied by measuring the data of total aeromagnetic field components. The FTG analysis (Full Tensor Magnetic Gradiometer) of the magnetic anomaly existing in the gulf was performed in order to give a different point of view to the geological structure of the gulf of Gökova in which there were intense seismic activities. Field components (Tx, Ty, Tz) of the aeromagnetic anomaly in the gulf of Gökova were estimated. Components obtained at the end of conversion were then applied the derivatives of Txx, Txy, Txz, Tyy, Tyz, Tzz and information about the location of the geological source which causes anomaly were taken. It was observed that the northern boundary of the ultramafic body had continued up to a distance of 9 km’s towards the northern coast of the gulf of Gökova. The anomaly in the gulf showed that ultramafic rocks, peridotites and the ophiolitic mélange of Datça peninsula had continued within the sea. The method has been useful in correct mapping of different geological units that have variable magnetic sensitivities and in revealing their locations

Anahtar Kelimeler

Gökova gulf, Datça, Bodrum, Magnetic, Gradient, Tensor, FTG

Kaynakça

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