Abstract:

Gediz Grabeni is a tectonic structure of approximately 200 km long, ranging from Manisa to Pamukkale. Manisa is one of the districts of Sarıgöl and Alaşehir and its surroundings with a risk of earthquake. One of the last major earthquakes in Graben was the Earthquake of M=6.9 magnitude on March 28, 1969. GNSS measurements were carried out in 2017 and 2018 for the study of tectonic movements in the work area. In addition to these observations, GNSS observations previously conducted in this region and at the same points (from 2013-2015) have also been used in the evaluation stage. GNSS measurement is used by GAMIT/GLOBK software. The horizontal speed components obtained from the GNSS results are calculated between 18 mm/year and 29 mm/year, while the low speed is calculated between -15 mm/year and -108 mm/year. As a result of the assessment of GNSS data, crashes were achieved in the inner part of the graven, and except for the graven, elevation values were achieved. GNSS results showed the characteristics of the region tectonics. According to the analysis, the G-K regime in the region is overwhelming. When the geodetic earthquake recurrence maps obtained from the results of demand analysis are studied, the period of recurrence of earthquakes of about 6 or 7 magnitude for the area is calculated between 400-500 years.

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