Investigation of surface deformations in Sarigöl by geodetic methods

In this research, the Sarıgöl fault line observed in the district center, the surface fractures caused by the 1969 Alaşehir earthquake were monitored by the sensitive nivelman method and the effect of groundwater on the fault line. The nivelman network, created for the sensitive nivelman method in the region, was established in 2017, including 2 nivelman lines and 14 reference points to cut the surface deformations perpendicular. A total of 11 precise leveling measurements were made in the region. Precision levelling measurements were carried out in four seasons due to the intensive agricultural irrigation in the region. Between the first precise nivelman measurement in July 2017 and the last measurement in August 2020, 240 mm of vertical deformation was observed. Data showing the water levels of DSI's underground wells in the area and its immediate vicinity were obtained from DSI. In the data obtained, drops in water levels were observed in spring and summer, and rises were observed in autumn and winter. It has been observed that there is a 10 m change in water levels during seasonal transitions (summer and winter). Although there is generally fluctuating movement at groundwater levels, deformations have been observed to persist continuously. According to the nivelman measurement results, surface deformation continued in seasonal transitions.