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ABSTRACT:The aim of this study is to conduct accuracy analyses of Land Use Land Cover (LULC) classifications derived from Sentinel-2 and Landsat-8 data, and to reveal which dataset present better accuracy results. Zonguldak city and its near surrounding was selected as study area for this case study. Sentinel-2 Multispectral Instrument (MSI) and Landsat-8 the Operational Land Imager (OLI) data, acquired on 6 April 2016 and 3 April 2016 respectively, were utilized as satellite imagery in the study. The RGB and NIR bands of Sentinel-2 and Landsat-8 were used for classification and comparison. Pan-sharpening process was carried out for Landsat-8 data before classification because the spatial resolution of Landsat-8 (30m) is far from Sentinel-2 RGB and NIR bands (10m). LULC images were generated using pixel-based Maximum Likelihood (MLC) supervised classification method. As a result of the accuracy assessment, kappa statistics for Sentinel-2 and Landsat-8 data were 0.78 and 0.85 respectively. The obtained results showed that Sentinel-2 MSI presents more satisfying LULC images than Landsat-8 OLI data. However, in some areas of Sea class Landsat-8 presented better results than Sentinel-2.

The Ismetpaşa segment of the North Anatolian Fault was ruptured during both the 1944 (Mw = 7.2) Gerede and 1951 (Mw = 6.9) Kurşunlu earthquakes. The field studies carried out in the aftermath of these two major earthquakes showed that the Ismetpaşa segment had experienced a creep movement. To monitor the surface creep, a geodetic network with six control points was established on the segment. This network was observed three times-in 1972, 1982 and 1992. Based on our evaluations of those observations, the creep on the segment was geodetically determined to be 1.02 cm/year (1972)(1973)(1974)(1975)(1976)(1977)(1978)(1979)(1980)(1981)(1982) and 0.93 cm/year (1982)(1983)(1984)(1985)(1986)(1987)(1988)(1989)(1990)(1991)(1992) respectively. In 1999, the North Anatolian Fault experienced two major shocks-the Mw = 7.4 Gölcük and Mw = 7.2 Düzce earthquakes-both on the western part of the Ismetpaşa fault. Using the global positioning system, our surveying team observed the network one more time in 2002 to assess whether these earthquakes affected the creep of the Ismetpaşa segment, or not. The evaluation of the observations revealed a creep of 0.78 cm/year for the period 1992-2002. This result reveals that the creep of the segment has decreased in a linear fashion between 1972 and 2002 and that it had not been triggered by the Gölcük and Düzce earthquakes.

Abstract. The Ismetpasa segment of the North Anatolian Fault is one of the rare places in the world where aseismic creep event has been observed. This segment was ruptured during both the 1944, Mw=7.2, Gerede and 1951, Mw=6.9, Kursunlu earthquakes. After these earthquakes, the segment has not experienced a major earthquake anymore. Starting from 1957, many studies using different technologies have been carried out to determine the creep rate of the segment. All these studies until 2002 revealed that the creep movement of the segment slowed down. The new observation campaign of the Ismetpasa geodetic network shows that the Ismetpasa segment has ceased the slowing trend and started to gain speed. This might be interpreted as an increasing earthquake risk for this segment.

Abstract. The Ismetpasa segment of the North Anatolian Fault (NAF) is a rare place where aseismic fault slip (creep) has been observed. Its creep behaviour has been monitored using different observation methods since the 1950s. The findings obtained from the studies until 1990s showed that the creep rate exponentially decreased before the major shocks in 1999, Golcuk (M w = 7.4) and Duzce (M w = 7.2). After these shocks, three GPS periods observation in 2002, 2007 and 2008 were carried out on the geodetic network established around the segment. The evaluations of these observations showed that the creep behaviour relaxed after the major earthquakes. This result demonstrates that the creep behaviour of the Ismetpasa segment might be a warning before future major earthquakes.