INVESTIGATION OF THE SEISMIC VELOCITY DISTRIBUTION AND CRUSTAL STRUCTURE OF TURKEY BY MEANS OF GRAVITY DATA

In this study, the apparent gravity density data was measured for Turkey using apparent density filter, and the seismic velocity distribution map was generated from this data cluster. By interpreting these two measured data clusters, three dimensional structure of the Conrad discontinuity was investigated. The apparent gravity filter is a kind of filter which is used in the apparent gravity measurements for different depth levels different than gravity data. In this study, considering previously measured distribution of the continental crustal thickness of the Anatolia, the density maps for different depth levels were formed and interpreted. The lowest and highest densities in different levels of Turkey are 2.6 gr/cm3, and 3 gr/cm3, respectively; and the mean density is 2.698 gr/cm3. The lowest and highest seismic velocities for different thicknesses were measured as 5.13 km/sec and 6.86 km/sec, respectively. However; the mean seismic velocity of Turkey for depths increasing up to 10 km until MOHO discontinuity was estimated as 5.66 km/s. The density and seismic velocity in the first 20 km of the continental crust have reached its highest values as 2.74 gr/cm3 and 5.86 km/sec, respectively. This zone is also the Conrad discontinuity between the lower and upper crusts, and its average depth is 16 km in Turkey. The Conrad discontinuity boundary, which developed between SIAL-SIMA, not to be observed in the East Anatolian High Plateau made us consider that SIMA had disappeared as a result of the geological evolution, and the available crust could only be SIAL in origin.

Keywords:

Seismic Velocity, Apparent Density, Continental Crust, Conrad Discontinuity Moho,

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ISSN: 0026-4563
Yayın Aralığı: Yılda 3 Sayı
Başlangıç: 1950
Yayıncı: Cahit DÖNMEZ

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