Akademik Veri Yönetim Sistemi
15th General Assembly of Asian Seismological Commission, Antalya, Türkiye, 3 - 07 Kasım 2024, ss.1, (Özet Bildiri)
The western part of Türkiye is characterized by complex tectonic due to the interactions between the Eurasian, African and Arabian plates. Its intense tectonics provide a proper setting to study the relationship between heat flow and depth of seismicity in the region. This study analyzed the region’s thermal structure and seismic characteristics by correlating reliable earthquake focal depths and heat flow measurements.
Recently updated heat flow data from western Türkiye shows that high values are associated with extensional tectonics, particularly in the graben systems of the region. These elevated heat flow values suggest a thin, thermally weakened lithosphere, resulting in a shallow brittle-ductile transition. Consequently, seismicity in these regions is predominantly characterized by shallow-focus earthquakes, typically within the upper 5-10 km of the crust. In contrast, areas of lower heat flow, such as the stable parts of the Menderes Massif, have a thicker, cooler lithosphere. Where the brittle-ductile transition occurs at greater depths, allowing the occurrence of both shallow and intermediate-focus earthquakes.
The distribution of focal depths to heat flow provides critical insight into the thermal and mechanical properties of the lithosphere in western Türkiye. The elevated heat flow in the region, resulting from lithospheric thinning and geothermal activity, limits the depth of the brittle-ductile transition, leading to predominantly shallow-focus earthquakes.