Determination of block rotations and the Curie Point Depths of magnetic sources along the NW–SE-trending Sülüklü–Cihanbeyli-Gölören and Şereflikoçhisar-Aksaray Fault Zones, Central Anatolia, Turkey

Abstract

The Şereflikoçhisar-Aksaray Fault (SAF) and Sülüklü–Cihanbeyli–Gölören Fault (SCGF) zones are located at the eastern and the western margins of the Salt Lake Basin-SLB (Tuzgölü Basin), central Anatolia, Turkey. These fault zones display intense magnetic anomalies along their trends and the positive amplitudes of these anomalies may reach up to 650 nT. In this paper, the body magnetisation directions are estimated from the selected five different magnetic anomalies with positive and negative peaks along these fault zones. Results of calculations indicated that local clockwise rotations are in the range of 34°E and 70°E. These magnetic anomalies were mainly created by the buried intrusive rocks. Locations of buried causative sources along the fault zones were determined from the analytic signal transformation of magnetic anomaly data. Curie Point Depths (CPDs) are also estimated from the aeromagnetic data to determine the thermal structure of the study area and they are correlated with the SAF and SCGF zones. It was found that the depth of magnetic crust varies from 11 to 22 km, consistent with the tectonic fault zones in the study area. The average value was determined as 16.7 km. These depths were correlated with the deep seismic reflection data and depths obtained from two windows in the seismic section, GTRS-87-801 are consistent with the CPDs. Shallow CPDs of magnetic sources are located along the SAF and SCGF to the east and west of the Lake Tuzgölü (Salt Lake) and it may be suggested that magnetic sources are probably located at the upper part of the crust.