Structure of the Hellenic Subduction Zone from Gravity Gradient Functions and Seismology

Abstract

The Normalized Full Gradient (NFG) method has widespread applications in the analysis of potential fields, especially the gravity and magnetic fields. This method is used to identify the lateral and horizontal density variations in the crust and lithosphere. In this study, the NFG method was applied to the gravity data of the Cretan Arc and its surroundings. Because of the tectonic features of the eastern Mediterranean, the Cretan Arc and the neighboring areas are seismically very active. Especially the subduction zone and the complicated crustal features have been defined applying many different geophysical methods. In this study, first the NFG method is tested with synthetic prisms (two cubes). After that, the NFG method was applied to the Bouguer gravity data of the Cretan Arc and its subduction zone (Hellenic subduction zone) and Hellenic subduction zone was defined with the foci depth data (USGS) along the south-north direction. Thus, geometry of the focal depth distribution has been created to determine probable media depths and their localizations. According to the NFG results, vertical structural transitions were observed at a depth ranging between 10 and 180 km. Also, these results were compared with the foci depth model and the other results of the related publications. Finally, some considerations in vertical solution with the NFG method have been presented and locations of the different structures at horizontally have been defined with application of the NFG method.

Deformation Analysis of East Mediterranean with using SSPX software

“…Mediterranean is associated with Eurasia, Africa, Arabian plates, micro plates and blocks. Many small tectonic structures such as collision, subduction, over thrust, transform fault lines, spiral opening are observed in this small area [3]. The main tectonic constructions of the region are given in Figure 1.…”

The Investigation of Hot Spots in Western Anatolia by Geophysical and Mining Approaches

“…According to Bozkurt (2001), this is taken up by a response of the continental lithosphere moving laterally away from zones of compression (tectonic escape), to minimize topographic relief and to avoid subduction of buoyant continental material. However, there is still a controversy about westward motion in western Turkey according to various researchers (Dewey and Sengor, 1979;McKenzie, 1972;Sengor et al, 1985; Dewey andŞengör, 1979;Jackson and McKenzie, 1984;Sengör et al, 1985;Eyidogan and Jackson, 1985;Şengör, 1987;Ambraseys, 1988;Seyitoglu and Scott, 1991;Şengör and Yılmaz, 1981;Okay et al, 1996;Barka and Reilinger, 1997;Bozkurt, 1996Bozkurt, , 2001Bozkurt, , 2003Bozkurt, , 2004Bozkurt, , 2007Emre, 1996aEmre, , 1996bHuguen, 2001;Yılmaz et al, 2000;Lips et al, 2001;Sözbilir, 2001Sözbilir, , 2002Gonenc and Akgun, 2011) of the study area. (color figure available online) 1992; Kocyigit et al, 1999;Sozbilir, 2004, 2006;Ankaya and Akcig, 1998).…”

Examination of the kinematic structures in İzmir (Western Anatolia) with repeated GPS observations (2009, 2010 and 2011)

“…Station (Makris and Stobbe, 1984;McClusky et al, 2000;Bozkurt, 2001;Gönenç and Akgün, 2012). (Wessel and Smith, 1995) was used to create these figures.…”

“…The reverse directions were inverted through the origin (modified from Kissel et al, 1987). Figure 1: The main tectonic framework of the Western Anatolia and its surroundings (Makris and Stobbe, 1984;McClusky et al, 2000;Bozkurt, 2001;Gönenç and Akgün, 2012). of earthquakes ranging from 0 km to 39.9 km between the years 2009 and 2011 in the study area (from BU, KOERI, National Earthquake Monitoring Center).…”