Curie Point Depths and Heat Flow of Eastern Anatolia (Turkey)

Abstract

The bottom of the magnetized crust determined from the spectral analysis of magnetic anomalies is generally interpreted as the level of the Curie point isotherm. The spectral analysis method to estimate the depth extent of magnetic sources was applied to the magnetic anomalies of Eastern Anatolia and compared with the tectonic regime and heat flow data in the region. The Curie point depth of eastern Anatolia ranges from 6 to 24 km. The computed Curie depths and the heat flow values derived by using Curie depths are consistent with the geological and the seismological findings of the region. Shallow Curie point depths and high heat flow values are seen between the Bitlis Suture Zone and the pontides. At the same time, this region might contain a thinner crust than expected.

GEOPHYSICAL REGIONAL GRAVITY MAP of TURKEY and ITS GENERAL ASSESSMENT

“…According to the model proposed by Keskin (2003), the Arabian Oceanic lithosphere, which subsides beneath the East Anatolian Accretion Prism, detached 11-13 million years ago, so the asthenosphere was uplifted from the detached segments and formed the volcanism in the East Anatolia ranging from 6 million years ago to recent. Another suggestion, which supports this idea, is the shallow Curie depths belonging to the East Anatolian region obtained in the study carried out by Pamukçu et al (2014). It can be interpreted that the uplifting asthenosphere material through these geodynamical processes might have melted-depleted the lower crust beneath the East Anatolian Accretion Prism (SIMA).…”

Doğu Anadolu Bölgesi̇’ndeki̇ Kabuk Yapisinin Düşey Ve Yatay Yönlü Anali̇zi̇

“…In the area between NAFZ and EAFZ near 100000 meter latitude, the structure transition in figure 4, the negative amplitude closures in figure 5 and the regions show high seismic activity in figure 6 were determined as the area which showed decreasing crustal thickness (Pamukçu et al, 2007), decreasing S-wave velocity , decreasing Curie depths and increasing heat flow (Pamukçu et al, 2014). Additionally, Pamukçu et al (2007) pointed out that in their Euler deconvolution study results, the 1400000 meter longitude was a border and the lithospheric structures may be different in west and east sides of this border.…”

“…Besides, the structures in convergence systems are involved in one of the tectonic component such as plateaus, suture zones, lithospheric flexures on the fore-plate, the deformation zones on the fore-plate/ back-plate, orogenic collapse/tension zones and the structures are formed with the uplifting of topography. The tectonic components for Eastern Anatolian region were examined in details in the studies of Al-Lazki et al, 2003;Gök et al, 2003;Türkelli et al, 2003;Sandvol et al, 2003a,b;Zor et al, 2003Zor et al, , fiengör et al, 2003Keskin, 2003;Pamukçu et al, 2007;Pamukçu and Ak盤, 2011;Pamukçu et al, 2014.…”

“…In these studies generally, it was emphasized that the large-scale shortining and thickening in the crust was started by the tension of the Arabian-Anatolian Plates convergence. The new approaches were presented by the studies (Al-Lazki et al, 2003;Gök et al, 2003;Türkelli et al, 2003;Sandvol et al, 2003a,b;Zor et al, 2003;fiengör et al, 2003;Keskin, 2003, Pamukçu et al, 2007Pamukçu and Ak盤, 2011;Pamukçu et al, 2014) realized after 2001 in Eastern Anatolia. In these new models, it was pointed out that the crustal thickening was not in the mentioned scale in previous studies (Rotstein and Kafka, 1982;McKenzie, 1972McKenzie, , 1976Dewey et al, 1986;Pearce et al, 1990).…”

“…Pamukçu and Ak盤 (2011) calculated the effective elastic thickness for explaining the mechanism of the topography which compensates the crustal thickness. The Curie depths and heat flow values were obtained by using aeromagnetic data by Pamukçu et al (2014). In the light of previous gravity and magnetic studies, in this study the estimation of the structure locations in Eastern Anatolia were done by applying the trend analysis, vertical and horizontal derivative methods (Butler, 1984;Gönenç, 2014) to the gravity data.…”