Interpretation of aeromagnetic data of the Sivas Basin in the central eastern Turkey

Abstract

Sivas Basin is located in the eastern part of the Central Anatolia. In this study, aeromagnetic data in the basin and surrounding area are processed and anomalies are interpreted to determine the approximate locations of the causative bodies and to reveal their relationship with the tectonic trends. The sedimentary basin is surrounded by strong magnetic anomalies from the south, east and northeast. The most apparent anomalies are observed in the E-NE of Zara, SW of Divriği and north of Kangal towns. These anomalies do not present significant directional change when they are reduced to the pole process. Causative bodies of the southern anomalies around Divriği and Kangal extend from NE to SW and northerly anomaly trend (to the N of Kangal) crosses the southern one (Divriği trend) in the Analytic Signal (AS) map. These trends are well-defined by the maxima points of the horizontal derivatives and these maxspots generally follow the boundaries of anomalies in the tilt angle map. The Kangal Fault controls the extensions of Divriği anomalies through the north and they are not observed in the area to the north of the fault. The Hafik Anomaly in the north of the study area is also differentiated from the anomaly group in the E-NE of Zara precisely, defining that they are created by two different causative bodies. Aeromagnetic characteristics of the ophiolites to the south indicate that they have different origin from the northern ophiolites group. Similarly, it is determined that the plutonic rocks in the south and north are also different origin emplacements considering their aeromagnetic responses, their mineral contents and ore deposit possibilities.