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The earthquake hazard of the wide plateau comprising significant dams around the East Anatolian Fault Zone (EAFZ) in eastern Türkiye is studied by means of the seismicity assessment and probabilistic seismic hazard analysis (PSHA). The fault segments of the EAFZ in the east of Kahramanmaraş city, which were previously assigned as a seismic gap, are shown to produce an earthquake in the order of at least Mw = 7.4. b values of the frequency–magnitude distribution calculated from the declustered Mw ≥ 3.2 seismicity after 1995 indicate significant temporal (a gradual decrease from 1.6 to 0.8 between 2010 and 2019) and spatial variations (between 0.75 and 2.1), leading to a short recurrence time estimation of as low as 90 years for an earthquake size comparable to the 2020 Sivrice earthquake (Mw = 6.7). No matter which attenuation relationship is used, the PSHA assuming a 475-year recurrence period results in considerably higher PGA values (average 0.25–0.64 g) as compared to the previous local and regional scale studies, suggesting higher seismic hazard than known so far. The presence of the seismic gap, the decreasing b value as an indication of rising ambient crustal stresses, the estimated shortest recurrence time of 90 years and the computed PGA values imply a significant earthquake hazard for the study area. Considering that the study area contains large cities with historic heritages, important industrial capacities and the existence of big crucial dams, requiring to be on alert in terms of seismic safety and preparedness of the population. [ABSTRACT FROM AUTHOR]

Coasts are dynamic environments that vary depending on time. Especially in the period we are in, the changes in coastal lines frequently occur due to antropogenic activity. Turkey, a riparian country of the Black Sea basin, is the source of many rivers that discharge into the Black Sea, both within its borders and through transboundary waters. There are quite large deltas in the mouth of these rivers. The Çoruh Delta, the subject of this study, was formed by sediments carried by a transboundary stream between Turkey and Georgia. Since the beginning of the 2000s located in the catchment areas within the borders of Turkey has gained Dam and Hydroelectric Power Plant construction work rate. In this context, the amount of sediment carried by the Coruh River naturally entered a downward trend. In this study, it is aimed to reveal the possible shoreline change in the Coruh Delta. Landsat satellite images of 1984, 1991, 2005 and 2019 were used in the study. Shorelines obtained from satellite images were evaluated together and traces of change were investigated. As a result of the study, it was determined that a dominant abrasion activity developed on the left bank of the river mouth, and abrasion and accumulation activities on the right beach. Net area loss in the delta was calculated as 63 ha. Between 1984 and 2019, a maximum decline of 238 m in the direction of land was detected in the shoreline of delta. [ABSTRACT FROM AUTHOR]

This study investigated the effects of active tectonism on the construction of hydraulic structures. Apart from the effect of dynamic loads, active tectonism can cause permeability problems. The focus of this study was on overcoming the permeability problems considering the economic yield in terms of grout curtain design and optimum dam axis location. The ground permeability of dam locations is one of the decisive factors affecting the feasibility and economic yield of dam construction. Techniques (such as grouting) for ensuring ground permeability reduction are generally expensive and time-consuming; the experience at the first location of the Turgutlu Dam is a case in point. Construction of the first location of Turgutlu Dam was planned on a fault terrace that is part of the North Anatolian Fault Zone, which is the most important active tectonic feature in Turkey. A grout curtain was planned to provide permeability reduction and ground treatment for the terrace material. However, the base elevation of the adjacent valley is deeper, and thus potential leakage to this valley was expected. In spite of its big reservoir area, the Turgutlu Dam Project became infeasible in terms of economic yield due to the ground remediation (construction of grout curtain) costs for this location. To solve this problem, the dam was relocated downstream to avoid the fault terrace, choosing an optimum grout curtain to minimize cost and improve water retention of the reservoir, and increase economic yield of the dam. [ABSTRACT FROM AUTHOR]

Key biodiversity areas (KBAs) are sites of global importance for biodiversity conservation. Their selection is based on standard criteria applied through a bottom-up, iterative process involving local stakeholders. This article presents the results of a study that applied the KBA methodology in Turkey. The KBA method uses four criteria: (1) globally threatened species; (2) restricted-range species; (3) congregations of species that concentrate at particular sites during some stage in their life cycle; and (4) biome-restricted species assemblages. In Turkey, we applied these criteria to 10,214 species of eight taxonomic groups: plants, dragonflies, butterflies, freshwater fish, amphibians, reptiles, birds and mammals. We identified 313 KBAs in Turkey, 303 of which trigger the KBA criteria for one or more taxonomic groups at the global scale. The remaining 10 sites trigger the KBA criteria at the regional scale only. These 303 globally important KBAs in Turkey cover 20,456,884 hectares, 26% of the country. Turkey’s natural landscapes, holding globally important biodiversity, are under immense threat and declining rapidly, both in quality and quantity. The nationwide threat assessment of KBAs revealed that dams, irrigation and drainage projects (i.e. water policies) form the main threat to Turkey’s biodiversity. Irrigation and drainage projects affect 225 KBAs and dams have an effect on at least 185 sites. KBAs raise attractive possibilities as being core areas where ecologically responsible governance models can be demonstrated, building on scientific and indigenous knowledge. [ABSTRACT FROM PUBLISHER]

This study discussed conflicts in a large-scale development project realized in an archaeological area. The dam reservoir of Yortanli constructed as a part of a contemporary irrigation project in Western Turkey conflicted with the antique settlement of Allianoi, which had developed in the same area around a natural thermal spring in the 2nd century ad. The aim was to present the protection decisions and implementations related with the archaeological site of Allianoi in the Yortanlı Dam Reservoir so that monitoring and criticism of its consequences can be possible in the future. The tools of the three disciplines, hydraulic engineering, structural engineering and conservation, were emphasized. The following conclusions were derived: The understanding of the protection-development conflict of archaeological heritage-dam relations in the case of Allianoi-Yortanlı necessitates the evaluation of its legal, administrative, technical, and managerial aspects with all related governmental and non-governmental parts. The presented evaluation provides an opportunity for the discussion of the validity of the protection intervention, which is reburial of the remains prior to water retention in the dam, within an international framework. The presentation of the details of the protection process may facilitate the monitoring and criticism of its consequences in the future. [ABSTRACT FROM PUBLISHER]

As a result of growing environmental consciousness, renewable energy sources such as hydropower are preferred. It is generated from domestic sources and is also the cheapest in terms of cost. In 2007, the annual electricity production of Turkey reached 191,558.1 GWh of which 35,850.8 GWh came from hydropower plants. The economically and technically exploitable potential of Turkey is 127,000 GWh/yr. Hydroelectric production depends on some factors such as the climate and topographical conditions. Therefore, the geographical conditions containing these factors play effective roles in hydroelectric generation. Sixty-five hydro dams having 48,184 GWh total annual generation capacities are in Turkey. In this article, generation capacities of these dams were investigated for the period from 1956 to 2007. The geographical regional distributions of these dams with respect to both numbers and generation capacities are discussed. Since geographical conditions also effect the construction types of hydro dams, regional distributions of the construction types and energy generation capacities of the different dam types were also evaluated. [ABSTRACT FROM PUBLISHER]

Dams constructed on the seismically active regions have a high-risk potential for downstream life and property. Strong ground motion can result in instability of the dam and strength loss of foundation. Active faults within the foundation of dam have the potential to cause damaging displacement of the structures. Appropriate design measures should be considered to obtain rational solution to the problem of catastrophic release of water from the reservoir, and especially to resist earthquake loads. Safety concerns for dams under the earthquake loads involve the seismic hazard evaluation of dam site for the overall stability of structure. Various types of analyses can be used, ranging from a simplified analysis to more complex procedures based on ground motion parameters and response spectra. This paper briefly evaluates seismic hazard analyses for dam structures, and introduces the analyses for thirty-six dams with height ranging from 15 to 195 m in Kızılırmak basin, Turkey. The seismic hazard analyses have indicated that peak ground acceleration varies within a wide range (0.09-0.45 g) for the dam sites of the basin. [ABSTRACT FROM AUTHOR]

The dams should be under safety and controls that are necessary are important engineering structures. In the dams activities in the related to safety and inspection begins in research, analysis and design phase. In the construction and operation phases continues throughout the life of the dam. During the operational phase, these controls are done with frequent periods. Aging with the dam, these controls would be fewer periods. In this study, different water levels, water load and depending on the weight of the dam itself vertical displacement consisting in the crest of dam is aimed determining by using IWST analyze method. As study area, Turkey's largest composite (Rock-Concrete) dam which is selected Keban dam. In this field, consisting from the point of 40 objects and 6 references, a deformation network was established. [ABSTRACT FROM AUTHOR]

After the construction of large engineering structures such as dams throughout life protection is required. Therefore, the structure may reveal the actual behavior by using the appropriate methods and instruments for monitoring water movement may occur is very important. This study Keban district in Elazığ province, on the Euphrates River, between the years 1965-1975 have been constructed for electrical energy production for concrete and rock fill type weight, body volume of 15,585,000 m³, elevation from river bed 163.00 m, the of the lake volume in the normal water level 31000.00 hm³ and lakes area of 675.00 km 2′ has been made in the Keban dams. Turkey's largest dam of Keban composite dam is open to business from the day performed by DSI technical staff has nearly 15 years of geodetic deformation measurements. In this study, the dam structure of the effect of movement as a whole considers the level of the reservoir water-dam's own weight under the influence of the interaction of keeping in mind for the past subject to review by a powerful database is intended to establish. [ABSTRACT FROM AUTHOR]

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In this study, dynamic behavior and earthquake resistance of Alibey earth dam was investigated. The dam was modeled with four node plane-strain finite elements (FE) and displacement-pore pressure coupled FE analyses were performed. Nonlinear material models such as pressure dependent and independent multi yield materials were implemented during the analyses. Transient dynamic FE analyses were performed with Newmark method. The Newton-Raphson solution scheme was adopted to solve the equations. Liquefaction and/or cyclic mobility effects were considered during the analysis. For the FE analyses, OpenSees (Open System for Earthquake Engineering Simulation) framework was adopted. [ABSTRACT FROM AUTHOR]

Abstract: Reservoirs constructed near urban areas pose a high-risk potential for downstream life and property. Turkey is one of the most seismically active regions in the world and has at least 1200 large dams with different types. Major earthquakes with the potential of threatening life and property occur frequently here. The Euphrates basin studied in this article is located in a seismically very active part of Turkey. The northern part of the basin is structurally cut by numerous faults. Many large dams are located on or close to these faults. In this paper we summarize the methods used for the analysis of seismic hazards and total risk, discuss the seismic hazards of thirty-two large dams constructed on the Euphrates basin on the basis of the seismic activity of the dam site and their total risk as based on physical properties and the position in the basin. The seismic hazard analyses have indicated that peak ground acceleration changes within a wide range (0.011 g and 0.564 g) for the dam sites of the basin. A seismic hazard map showing the equivalent PGA (peak ground acceleration) values was developed so as to use for the preliminary analysis of dam structures, which will be designed in the basin. The total risk analyses depending on the seismic hazard rating of dam site and risk rating of the structure have concluded that fifteen large dams have high-risk class in the basin. These dams must be analyzed with high priority and redesigned to increase the safety of the embankments and their appurtenant structures, if necessary. [Copyright &y& Elsevier]

Objective: We evaluated adult patients with isolated chest injuries caused by falls from roofs in and around the city of Sanliurfa. Materials and Methods: Between June 2008 and April 2010, 52 adult patients with isolated chest trauma caused by falls from roofs who were admitted to the Department of Thoracic Surgery were analyzed retrospectively. Cases were evaluated according to sex, age, developing thoracic injuries, diagnostic and treatment modalities, morbidity and mortality. Results: Among 52 patients, 28 cases (53.85%) were males and 24 (46.15%) females. The age range varied between 17-87 years and the average was 39.8 years. 43 cases (82.69%) were detected in June, July, August and September, 9 cases (17.31%) occurred in the other months. 36 Rib fracture (69.23%), 3 sternal fractures(5.76%), 7 isolated hemothorax (13.46%), 10 isolated pneumothorax (%19.23), 14 haemopneumothorax (%26.92), 30 lung contusion (57.69%), 11 subcutaneous emphysema (%21.15) cases were seen. Tube thoracostomy was carried out in 31 cases (%59.61)and thoracotomy was done in 1 case (%1.92). Conclusions: In our country, especially in the south-eastern region of Anatolia, falling from a roof in the summer months is quite common, and is a specific place in cases of trauma and falls from height and multiple organ injuries should be evaluated with a special emphasis.A protective and preventive approach is as important as the treatment procedure. [ABSTRACT FROM AUTHOR]

Dams, which indeed have many benefits, are hydraulic structures that retain sediments in the rivers on which they are built. This property of dams can cause hydrological and geomorphological alterations in parts of the river beneath these structures. Among the three largest coastal valleys of the Anatolian Peninsula, Kızılırmak Delta suffers from geomorphological changes as a result of large dams being constructed there. Sediment is retained in the dam reservoir, which results in a considerable decline in the total amount of sediment that reaches the Kızılırmak Delta. When Altınkaya and Derbent Dams were constructed within the vicinity of the delta, sediment input nearly stopped. The most affected part of the delta was a 4 km stretch of shoreline and a coastal strip situated at the east of the river mouth. The aim of our study was to determine the erosion rates and the shoreline changes in the delta between the oldest available date (1951) before construction of the large-scale dams on the Kızılırmak River and the latest data (2017). To compute the net shoreline changes and erosion rates over these 66 years, we used geographic information system software. This 4-km stretch of shoreline at the east of the river mouth was investigated as two subdivisions. The study timeframe was divided into subperiods to uncover the impacts of the dams over time, and the net shoreline changes were calculated for each subperiod. According to the net shoreline computations for Subregion I, the delta retreated by 604.85 m. In Subregion II, the delta shoreline advanced by an average of 231.68 m until 1990, but it retreated by an average of 409.05 m between 1990 and 2017. According to the linear regression rate (LRR) analysis, the calculated erosion rate in Subregion I is − 11.46 m/year, and in Subregion II is 6.10 m/year for the period between 1951 and 1990 and − 15.10 m/year for the period between 1990 and 2017. When the results of net shoreline movement (NSM), LRR, and end point rate (EPR) were considered together over different time periods, it was clear that dams, which were constructed within the vicinity of the delta, were increasing the retreat in delta shoreline. [ABSTRACT FROM AUTHOR]

The aim of our study was to determine the erosion rates and shoreline changes in the Yeşilırmak Delta (Delta) between the oldest available date (1953) before construction of the large-scale dams on the Yeşilırmak River in northern Turkey and 2017. To clearly illustrate the impacts of the dams on the Delta, we investigated the relationship between the dams and shoreline changes. To compute the net shoreline changes and erosion rates over these 64 years, we used a Digital Shoreline Analysis System. To digitize the shoreline changes at the mouth of the Yeşilırmak River, 1:25000-scaled topographic maps from 1957, panchromatic aerial photographs from 1962, a KH-9 Hexagon satellite image from 1980, an Ikonos satellite image from 2002, and a WorldView-2 satellite image from 2017 were used. The west and east sides of the river mouth were divided into six main groups and assessed. Each group included a time series for the shorelines. The groupings were based on the time series. For each group, the net shoreline change (m) was calculated using the net shoreline movement (NSM), and erosion rate (m/year) was calculated using the linear regression rate (LRR). According to NSM computations, net shoreline change varied from − 235.04 to 379.18 m. The greatest evolutions in net shoreline change were observed for group I, with a minimum of − 1101.11 m. According to LRR analysis, the calculated erosion rate varied from − 6.83 to 19.06 m/year. The greatest changes in erosion rate were observed for group II, with a minimum of − 30.63 m/year. There is a close relationship between the construction dates of the dams in the Yeşilırmak Basin and the shoreline changes in the Delta. [ABSTRACT FROM AUTHOR]