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In this study, the seismicity of the Erzincan Plain and its surroundings, which are part of the Upper Euphrates Section in the Eastern Anatolia Region was investigated. Erzincan Plain is a tectonic plain developed on the North Anatolian Fault Zone (NAFZ). However, the NE-SW trending North-East Anatolian Fault (NEAF) in the north of the plain and the Ovacık Fault (OF) in the southeast of the plain affected the development of the plain. The Erzincan Plain, which is tectonically located at the intersection of faults, has experienced large earthquakes that have been effective in the past to the present. Seventeen of these devastating earthquakes occurred in the historical period and two in the instrumental period (1939 and 1992 Erzincan earthquakes). Severe earthquakes have occurred that seventeen of these earthquakes occurred in the historical period and two in the instrumental period. Considering this situation of the plain environment, spatial and intensity analyses were performed using 46 earthquake data with a magnitude of Mw =4 that occurred in the instrumental period. Based on the analysis, destructive earthquakes are concentrated in and around Erzincan, situated on the NAFZ. Moderate and low-intensity earthquakes, on the other hand, are more common in the east and southeast of the plain. The high concentration of severe earthquakes around Erzincan indicates a high risk in these areas. Therefore, it is advisable to establish new settlement areas outside the main fault zone, on gently sloping plains to the west of the Erzincan plain, which are more suitable in terms of ground. [ABSTRACT FROM AUTHOR]

In this study, it is aimed to determine the relative tectonic activity of faults controlling Varto Basin with geomorphic indices. Varto Basin is located in the southeast of Karlıova, between Bingöl and Serafettin Mounts. Varto Fault, which intersects with the East Anatolian Fault in Karlıova and the continuation the North Anatolian Fault towards southeast, has been effective in the formation of the basin. Being right lateral strike slip, Varto Fault starts in the east of Karlıova Triple Junction and continues towards southeast in the form of a zone. Due to this location, tectonic activity in and around the basin is very high. The young tectonic movement of the basin has been revealed by geomorphic index analysis method. In these analyses, digital elevation model (DEM), stream, fault and geology data were used as the basic data set. A total of 43 sub-basins reflecting tectonic activity have been identified around the basin periphery and on Varto Fault zone (VFZ). For this purpose, hypsometric integral (Hi), hypsometric curve (Hc), basin asymmetry factor (AF), drainage basin shape (Bs), stream length-gradient index (SL), channel sinuosity (S) and elongation ratio (Re) analyses were performed. Along with the basin analyses, the measurements of mountain front sinuosity ratio (Smf) and valley floor width-to-valley height ratio (Vf), which are frequently used in the determination of active tectonics, and streams longitudinal profile analyses were done in the basin. According to the results of the analyses, tectonic activity classes of the basins were determined and their distributions were shown. According to these results, except for the two basins in the south of the Varto basin and one located in the VFZ, all others fall into very high and high tectonic activity classes. Index results, earthquakes, hot and cold sources along the fault zone and geomorphological figures prove that active tectonics are intense in and around Varto Basin. [ABSTRACT FROM AUTHOR]

In this study, the reflections of the Sivrice-Elazig earthquake on geomorphology and the linear lines formed in the Karakaya Dam Lake after the earthquake have been analysed. On 24th 2020, a 6.8 magnitude earthquake occurred in the village of Çevrimtas, the epicenter of which is located in Sivrice district to the south of Elazig. In the earthquake, 41 people lost their lives, 37 of them in Elazig and 4 of them in Malatya, and tens of thousands of buildings were heavily damaged. After the earthquake on 30th January 2020, It was reported as water or gas outflow by a group of researchers doing research in the field that white lineaments on the dam were observed overlapping with the fault. However, after this report, it has been observed through field studies that these lineaments have recurred in the same areas on different dates. In the first field observations, the presence of foam and plant fragments in the white linear lines coinciding with faults that the white lineaments are outgassing have been found suspicious. For this reason, in the areas where East Anatolian Fault zone offsets Euphrates Valley, an experiment has been done by leaving straws and foam on the dam lake. According to the experiment's results, It was observed that the material left in the absence of the wave was randomly dispersed, and that foam formed by the wave onset and the material left on the surface of the water were aligned in the same direction with the fault and formed white linear lines. These data show that the white linear lines formed on the lake surface are a special form caused by the wave effect, depending on the morphology and air movements, apart from the gas outflow. [ABSTRACT FROM AUTHOR]

In this study, a spatial and temporal analysis was conducted for natural disasters that occurred in Ağrı province, located in eastern Turkey. Natural disasters often occur in the province due to geological, geomorphological, climatic, and hydrographic characteristics. According to data from the Disaster and Emergency Management Presidency, the province of Ağrı is one of the most vulnerable in our country in terms of natural disasters. Consequently, the disaster statistics from 1955 to 2017 were analyzed in this study to reveal the unsafe condition of this province. A total of 955 natural disasters have occurred in the province of Ağrı according to the disaster data report. Among these disasters, torrents and floods take the first place, followed by earthquakes, landslides, rockfalls, and avalanches. The Mann–Kendall test, Sen’s slope, Spearman’s Rho, and Kernel density estimation methods were used to determine the future trends of natural disasters in the province. According to the findings of the study, there has been a significant increase in the number of disasters in the province. In the trend analysis findings, the increase in natural disasters between 2010 and 2017 has drawn attention. Geographic Information System programs were used to create thematic maps of disasters and to reveal the average annual disaster frequency, total number of people affected, and spatial distribution of disasters. The distribution maps show that the intensity of natural disasters increases in the areas where the rivers open to the plain, on the slopes, and in fault zones. [ABSTRACT FROM AUTHOR]

In this study, the morphometric characteristics of the river basins causing flood and overflow in Bulancak, west of Giresun, were evaluated. Bulancak is a settlement under the flood and overflow risk caused by the Pazarsuyu, İncüvez, Kara and Bulancak streams, which takes its source from the Giresun Mountains in the south. Pazarsuyu stream basin is much wider than other rivers and the flood and overflow risk is higher. Although the other basins have small basins, they are at risk for these streams due to the interventions made on the stream beds. According to the data from the Disaster and Emergency Management Authority (AFAD), nineteen floods occurred in these river basins between 1948 and 2012. According to geomorphological observations, with rapid population increase, the settlement was seen to expand from the coast to the inner parts and to occupy the river valleys. The use of stream beds in river valleys has caused narrowing of stream sections. When the morphometric features of the basins are combined with this situation seen in the lower basin, it has been determined that the frequency of the floods and overflows that turn into a disorder increases. Area and relief morphometry analyses of the basins were analyzed in order to determine the effect of geomorphological features on flood and overflow formation in Bulancak. Drainage density, stream frequency, basin form, length ratio and Gravelius index analyses were made to determine the spatial morphometric properties of the four river basins. In order to determine Relief morphometry properties, basin relief, relief ratio, ruggedness value, Time of Concentration, hipsometric curve and integral analyses were applied. In the analyses made using Geographic Information Systems (GIS), Digital Elevation Model (DEM) and geology maps covering the study area were used as basic data. According to the results of the analysis, the drainage density, stream frequency and ruggedness of all basins are high and basin shapes are narrow and long. Hipsometric curves and integral values indicate that the basins are at the stage of maturity close to bloom. Incüvez Dere and Bulancak Stream basins are seen to have higher flood and overflow potential according to the other basins. [ABSTRACT FROM AUTHOR]

The aim of this study is to analyze the erosion susceptibility of the area between Ballı and Memikan streams, which are located in the northeast of Malatya. In the research area, Baskil migmatites formed by plutonic rocks such as granite, granodiorite and gabbro and Eosen units formed by sandstone, marl, and conglomerate have a wide surfacing area. Very severe erosions have been taking place in the northeast of Malatya due to climatic characteristics, lithological structure and destruction of vegetation. In order to determine the effect of the erosion and erosion susceptibility, certain analyses have been done using Geographic Information Systems (GIS) and Remote Sensing (RS) software. In this analysis data about lithology, slope, stream density, vegetation and soil brightness have been used. These factors having an effect on erosion have been classified according to their importance and the weight value of each factor has been assigned according to their effect on erosion. Layers, whose weight values have been assigned, have been overlaid using Raster Calculator and erosion susceptibility map has been created. According to the results of the analysis, areas, whose erosion susceptibility is very low, account for 11%, areas in lowclass account for 16 %, 27 % of the area is in medium class, 37 % of the area is in high class, and finally 9% of the area is in very high class. Based on this, erosion susceptibility has been determined to be very high. According to these results, efforts of combating erosion in the region must be carried out with determination. [ABSTRACT FROM AUTHOR]

In this study, the climatic characteristics of Rize were determined using the long-term (1970-2014) observation data of Rize, Pazar, Hopa and Trabzon meteorological stations. In addition, trend analyses were performed through the Mann-Kendall method using the temperature and precipitation data of these stations. These 4 stations where the observation data were obtained are located in the coastal belt in the Eastern Black Sea. Although the distances between the stations are not so long, extreme changes are observed in the climatic factors. Rize has very different properties in terms of climatic characteristics in Turkey and the Eastern Black Sea. Local climatic conditions which are unique to Rize are observed with the orography and exposure effects. In Rize, the long-term annual mean temperature is 14.3°C and the annual mean precipitation is 2254.4 mm. The lowest temperature was measured as 3.4ºC in February and the highest temperature as 26.7ºC in August. The annual mean time of sunny day is around 5-6 hours. The long-term annual mean pressure was measured as 1014 mb in Rize. The predominant wind direction is south-west. This is because of the winds blowing from south towards the coastal belt as well as it to be a region which is open to air flows through the Black Sea. Considering the temperature, precipitation and sunshine duration, the number of foggy and cloudy days seems to be high. This ensures low rate of evaporation. In Rize, where there is no water lacking, soil is always humid and vegetation is very bushy and green. Considering these characteristics, it is seen that perhumid and moderate climate conditions are experienced in Rize. According to the Mann-Kendall and Sen analysis results, significant tendencies to increase are seen in the temperature ratings in the stations except for Pazar and in the amounts of precipitation in the stations except for Hopa. According to the trend analyses, Rize shows a more stable characteristic compared with the other stations. [ABSTRACT FROM AUTHOR]

The aim of the study is to conduct landslide susceptibility analysis for Şepker Stream Lower Basin. Şepker Stream flows in western Adıyaman from north to the south into Göksu Stream. In Şepker Stream Upper Basin lithology is composed of limestone, whereas the lower basin is composed of volcanic and clastic rocks. Due to the lithological structure of the lower basin extensive landslides have developed along the Şepker Stream Valley. Tepecik, Damdırmaz and Şerefli regions are the areas where most of the landslides were observed. Damdırmaz and Şerefli settlements were built directly on landslides. Especially during spring, after snowmelt and heavy rainfalls, landslides that affect the settlement, roads and agricultural areas are observed. With rainfall, the seasonal lake located in northern Tepecik, lithological structure and high slope values in valley shoulders trigger the formation of landslides. To determine the landslide susceptibility in Şepker Stream Lower Basin, weighted overlay method utilized in Geographical Information Systems (GIS) and Remote Sensing (RS) studies was used. In this method parameters such as lithology, the distance to fault lines, distance to streams and closure of vegetation are used. Field observations were conducted to verify the analysis results. Landslide inventory map was plotted based on the field studies and the susceptibility map was produced by overlaying parametric maps with the landslide inventory map. Based on the resulting map, 39% of the areas in Şepker Stream lower basin were low susceptibility; 23% were moderate susceptibility; and 38% were high and very high susceptibility areas. Based on these values, landslide risk should be considered as the primary risk in planning studies that would be conducted in Şepker Stream Lower Basin. [ABSTRACT FROM AUTHOR]