An aspect of the subsurface structure of the Burdur-Isparta area, SW Anatolia, based on gravity and aeromagnetic data, and some tectonic implications

M Nuri Dolmaz

doi:10.1186/bf03352016

Abstract

AbstractGravity and aeromagnetic analyses were conducted in the Burdur-Isparta area of Turkey in order to identify the subsurface structure and tectonics of the region independent of surface cover. The analytic signal of the aeromagnetic anomalies was first calculated to delineate the source fields of these anomalies. The magnetic signatures were found to correlate well with the intrusives associated with the subduction of the African oceanic lithosphere and with the ophiolitic nappes in the region. The residual aeromagnetic anomalies mostly orientate in the N-S direction, implying the presence of remanent magnetization. Based on the shape analysis of aeromagnetic anomalies, the region appears to have rotated clockwise. The magnetic anomalies were found to continue upward to 5 km a.s.l. The upward continued map shows deep effects of the sub-crustal magnetic sources. Based on the Bouguer gravity anomalies, the thickness of the crust in the study area is between 33 and 37.5 km. Major extensive NE- and NW- as well as N-trending faults are identified that coincide with the Lake Burdur, Lake Beysehir and Kovada grabens, respectively. Lake Egirdir is also devoid of any magnetic sources. As a final step, the maxima of the horizontal gradient of the gravity data were calculated. The maxima show that the major geological formations and the structural trends in the area are remarkable. The boundaries of the various geological formations can be identified based on the boundary analysis of the gravity and the analytic signal of the aeromagnetic data. The change in the nature of the anomalies reflects the imprints of intense deformation associated with major tectonic activity of the African-Eurasian plate convergence zone.

Highlights

The study area is located in Isparta Province, SW Anatolia, Turkey, which is situated at the boundary between the rapidly extending West Anatolian Extensional Province (WAEP) and the relatively stable Anatolian plateau (CAOP; Fig. 1)
In order to understand the distribution of magnetic sources in the study region, the analytical signal of the aeromagnetic anomalies were computed based on the above procedure (Fig. 4)
Shape analysis of the selected anomalous regions of the aeromagnetic anomaly map of the Burdur-Isparta area in SW Anatolia indicated that the region generally rotated clockwise

Summary

Introduction

The study area is located in Isparta Province, SW Anatolia, Turkey, which is situated at the boundary between the rapidly extending West Anatolian Extensional Province (WAEP) and the relatively stable Anatolian plateau (CAOP; Fig. 1). We have integrated aeromagnetic and gravity data in the Burdur-Isparta area with the objective of identifying possible subsurface structures and magnetic sources in the study region independent of surface cover. The results from such an investigation on the potential field anomalies in this seismically active region would contribute to a better understanding of the tectonics of SW Anatolia. In order to understand the distribution of magnetic sources in the study region, the analytical signal of the aeromagnetic anomalies were computed based on the above procedure (Fig. 4) The application of this technique to the aeromagnetic data of the Burdur-Isparta area revealed that some highly magnetized bodies are the main sources of high magnetic anomalies.

Lake Beysehir

Conclusion