Over the past century since the Republic of Türkiye was founded,its national security mechanisms have undergone a process of transformation from military-dominated to civilian government-dominated,and the ideolog...Over the past century since the Republic of Türkiye was founded,its national security mechanisms have undergone a process of transformation from military-dominated to civilian government-dominated,and the ideology guiding its national security strategy has gradually transitioned from Kemalism to Erdo?anism.At the present stage,Türkiye's national security strategy is prominently characterized by its geographical and cultural duality,the expansivity deep-rooted in its history and religion,and an enterprising response to its geopolitical realities.Such a strategy will comprehensively shape Türkiye's practice of preserving national security and guide the future of its security policies,prompting the country to seek a balance between its differentiated perceptions of identity and generalized national interests.展开更多
This study focuses on the field reconnaissance efforts for investigating ground deformation behavior and building foundation performance in Iskenderun.Many structures experienced significant damage or collapsed due to...This study focuses on the field reconnaissance efforts for investigating ground deformation behavior and building foundation performance in Iskenderun.Many structures experienced significant damage or collapsed due to strong ground shaking in the coastal Iskenderun district of Hatay during the 2023 Kahramanmaras earthquake sequence.Many buildings were also impacted by ground failure due to liquefaction of deposits in the area.Preliminary information regarding the general subsurface profile and post-earthquake data collected during the reconnaissance was used to perform simplified liquefaction and lateral spreading analyses.The empirical methods provide first order estimations of settlements and lateral spreading but are not sufficient when the nature of the structure-soil-structure interaction and earthquake sequence is considered.Measurements of vertical displacements and building tilt,liquefaction manifestations,and structural and foundation parameters potentially affecting foundation settlements including foundation geometry,building contact pressure,and building elastic period were used to evaluate seismic response of the ground and the structures through empirical procedures.Most of the buildings exhibited poor to mediocre foundation performance due to liquefaction-prone subsurface profiles,especially on the coastline.Ongoing field and numerical research will reveal the cause of significant ground failure in the area as well as refined estimates for the seismic deformations.展开更多
Spring waters consumed for drinking purposes should be clean and quality. These waters with balanced mineral distribution, which do not contain organic substances, whose physical and chemical caharacteristics comply w...Spring waters consumed for drinking purposes should be clean and quality. These waters with balanced mineral distribution, which do not contain organic substances, whose physical and chemical caharacteristics comply with certain quality parameters and which do not negatively affect human health are identified as healthy water. Kuvars water is a spring water which is pumped out from the draw well at the Camurluk stream basin of Maltepe province of Istanbul and filled into bottles. The Camurluk stream basin is approximately 4.5 km2. The Camurluk stream basin is sedimentary rocks and talus deposit outcrops. Reaching of trace elements, which is found more in the talus deposit samples than outcropping quartzarenite at the basin, to underground aquifer as ions under effect of rains, water rock interaction, leakage and filtration, is prevented by illite type clay levels existing within the talus deposit stack, which have upto 20 cm thickness. However, negative effects of the excavation that were made at the talus deposit reflect on the hydrologic cycle and chemical compositions of well waters. This effect was at first negatively affected the physical characteristics of the well waters. During the rainy periods, the water in the excavated area which was enriched with respect to the suspended sediments was percolated into the groundwaters from the joints and cracks of the quartzarenite. The turbidity value measured in the well waters of K2 and K3 were determined as 40.3 NTU and 34.2 NTU respectively. Although at the basin, the aquifer of underground water and the well waters being managed are quartzarenite, the fact that water types belonging to well waters differ (they are not same) according to the Piper diagram and when the heavy metal content of the water of well numbered KS1 is taken as basis, that some heavy metals such as Al3+, Fe2+, Ni2+, Mn2+ and Cu2+ be enriched 3 to 40 times in KS2 and KS3 well waters, are caused by talus deposit—water interaction at the excavation area. After a rainfall, in the water that became turbid with the water-talus deposit interaction at the excavation area, the water-mineral interaction has caused the limit value for drinking water suggested by World Health Organization (WHO) to be exceeded with the Al3+ concentration of 189 ppb detected in KS2 well water and Fe2+ concentration of 185 ppb has caused to approach the drinking water limit value of 200 ppb permitted by World Health Organization (WHO), United States Environmental Protection Agency (EPA), European Union (EU) and Turkish Standards (TS). Therefore, at the water basins where bottled spring waters consumed for drinking purposes are produced, technical undertakings that shall disturb the stability of geological units should not be permitted.展开更多
Karapınar region(Konya,Türkiye)is one of the important regions of the world in terms of sinkhole formations.The research aimed to map the sinkholes in detail,to determine their spatial distribution and geometrica...Karapınar region(Konya,Türkiye)is one of the important regions of the world in terms of sinkhole formations.The research aimed to map the sinkholes in detail,to determine their spatial distribution and geometrical parameters.For this purpose,the long axes,short axes,depths and the proximity to settlements of the sinkholes were measured and their circumferences and areas were calculated.During the studies,the relationship of the sinkholes with lithology,their cross sections,shapes and the related structures were determined and the sinkholes were divided into five main groups as following:Basement rock sinkholes,Obruk Plateau sinkholes,Seyithacı sinkholes,Siyeklik sinkholes and Basin sinkholes.The d/l ratios of each sinkhole group were separately determined and interpreted.Accordingly,most of the d/l ratios are smaller than 0.2.Namely,the long axes are higher than the depth and it indicates that the shallow and wide sinkholes are common in the region.It has been determined that the fracture systems in the region,as well as the lithology and groundwater factors,are quite effective in the formation and distribution of the sinkholes in the Karapınar region.Considering the distance of the sinkholes to the settlements,Seyithac?sinkholes are the most risky group in the region because they are deep and close to the settlements.展开更多
Recent geodetic and seismological observations of two major earthquakes in southeastern Türkiye in February 2023 have revealed complex rupture initiation,propagation,and segmentation along the East Anatolian Faul...Recent geodetic and seismological observations of two major earthquakes in southeastern Türkiye in February 2023 have revealed complex rupture initiation,propagation,and segmentation along the East Anatolian Fault Zone(EAFZ)and surrounding regions.However,the role of upper crust structures along the EAFZ in determining the diverse rupture processes of this earthquake doublet remains unclear.To further investigate this,we employed double-difference location and seismic tomography techniques to determine high-resolution seismic velocities(V_(P),V_(S))and Poisson’s ratio(σ)structures using a multiparameter joint tomographic algorithm.Our dataset includes 100,833 high-quality source-receiver travel-time pairs of P-and Swaves.We find that the unique rupture processes of this earthquake doublet were primarily influenced by contrasting crustal seismic structures and localized geological settings.The M_(w)7.8 mainshock was initiated within a transitional edge zone characterized by a rigid part(asperity)of the seismogenic zone with sharp contrast variations in rock strength ranging from low to high along the EAFZ.In comparison,the M_(w)7.6 rupture originated in a ductile belt featuring fluid saturation with low-VP,low-VS,and high-σvalues that extended parallel to the Cardak Fault.The pronounced contrast structures observed along the former rupture can be attributed to the oblique collision system between the weakened section of the east Anatolian plateau and the brittle Arabian platform,while the latter rupture was initiated within the ductile structure associated with fluid intrusion caused by the northward subduction of the Cyprus slab and subsequent detachment.Furthermore,the occurrence of the first earthquake(E1)serves to alleviate shear stress on the second earthquake(E2)fault,potentially impeding the initiation of an E2 rupture.On the contrary,this event also significantly reduces the normal stress acting on the E2 fault due to a double left-lateral strike-slip system within a triangular region.This reduction not only results in a decrease of fault friction force and an increase in rock porosity but also induces lower strain drops and the redistribution of Coulomb stress,thereby contributing to the initiation of the E2 event.The proposed rupture pattern exceeds the conventional model that governs individual earthquake ruptures,offering new insights for mitigating potential seismic disasters in Türkiye.The lessons learned from this doublet event can contribute to reevaluating the ongoing risk of damaging earthquakes in China’s South-North Seismic Zone or other regions worldwide with comparable geological conditions.展开更多
文摘Over the past century since the Republic of Türkiye was founded,its national security mechanisms have undergone a process of transformation from military-dominated to civilian government-dominated,and the ideology guiding its national security strategy has gradually transitioned from Kemalism to Erdo?anism.At the present stage,Türkiye's national security strategy is prominently characterized by its geographical and cultural duality,the expansivity deep-rooted in its history and religion,and an enterprising response to its geopolitical realities.Such a strategy will comprehensively shape Türkiye's practice of preserving national security and guide the future of its security policies,prompting the country to seek a balance between its differentiated perceptions of identity and generalized national interests.
文摘This study focuses on the field reconnaissance efforts for investigating ground deformation behavior and building foundation performance in Iskenderun.Many structures experienced significant damage or collapsed due to strong ground shaking in the coastal Iskenderun district of Hatay during the 2023 Kahramanmaras earthquake sequence.Many buildings were also impacted by ground failure due to liquefaction of deposits in the area.Preliminary information regarding the general subsurface profile and post-earthquake data collected during the reconnaissance was used to perform simplified liquefaction and lateral spreading analyses.The empirical methods provide first order estimations of settlements and lateral spreading but are not sufficient when the nature of the structure-soil-structure interaction and earthquake sequence is considered.Measurements of vertical displacements and building tilt,liquefaction manifestations,and structural and foundation parameters potentially affecting foundation settlements including foundation geometry,building contact pressure,and building elastic period were used to evaluate seismic response of the ground and the structures through empirical procedures.Most of the buildings exhibited poor to mediocre foundation performance due to liquefaction-prone subsurface profiles,especially on the coastline.Ongoing field and numerical research will reveal the cause of significant ground failure in the area as well as refined estimates for the seismic deformations.
文摘Spring waters consumed for drinking purposes should be clean and quality. These waters with balanced mineral distribution, which do not contain organic substances, whose physical and chemical caharacteristics comply with certain quality parameters and which do not negatively affect human health are identified as healthy water. Kuvars water is a spring water which is pumped out from the draw well at the Camurluk stream basin of Maltepe province of Istanbul and filled into bottles. The Camurluk stream basin is approximately 4.5 km2. The Camurluk stream basin is sedimentary rocks and talus deposit outcrops. Reaching of trace elements, which is found more in the talus deposit samples than outcropping quartzarenite at the basin, to underground aquifer as ions under effect of rains, water rock interaction, leakage and filtration, is prevented by illite type clay levels existing within the talus deposit stack, which have upto 20 cm thickness. However, negative effects of the excavation that were made at the talus deposit reflect on the hydrologic cycle and chemical compositions of well waters. This effect was at first negatively affected the physical characteristics of the well waters. During the rainy periods, the water in the excavated area which was enriched with respect to the suspended sediments was percolated into the groundwaters from the joints and cracks of the quartzarenite. The turbidity value measured in the well waters of K2 and K3 were determined as 40.3 NTU and 34.2 NTU respectively. Although at the basin, the aquifer of underground water and the well waters being managed are quartzarenite, the fact that water types belonging to well waters differ (they are not same) according to the Piper diagram and when the heavy metal content of the water of well numbered KS1 is taken as basis, that some heavy metals such as Al3+, Fe2+, Ni2+, Mn2+ and Cu2+ be enriched 3 to 40 times in KS2 and KS3 well waters, are caused by talus deposit—water interaction at the excavation area. After a rainfall, in the water that became turbid with the water-talus deposit interaction at the excavation area, the water-mineral interaction has caused the limit value for drinking water suggested by World Health Organization (WHO) to be exceeded with the Al3+ concentration of 189 ppb detected in KS2 well water and Fe2+ concentration of 185 ppb has caused to approach the drinking water limit value of 200 ppb permitted by World Health Organization (WHO), United States Environmental Protection Agency (EPA), European Union (EU) and Turkish Standards (TS). Therefore, at the water basins where bottled spring waters consumed for drinking purposes are produced, technical undertakings that shall disturb the stability of geological units should not be permitted.
基金supported by the Konya Provincial Directorate of Disaster and Emergency(AFAD)within the scope of the“Detection of the Sinkhole Around Karapınar”Project(No.2020K14-138637-2)。
文摘Karapınar region(Konya,Türkiye)is one of the important regions of the world in terms of sinkhole formations.The research aimed to map the sinkholes in detail,to determine their spatial distribution and geometrical parameters.For this purpose,the long axes,short axes,depths and the proximity to settlements of the sinkholes were measured and their circumferences and areas were calculated.During the studies,the relationship of the sinkholes with lithology,their cross sections,shapes and the related structures were determined and the sinkholes were divided into five main groups as following:Basement rock sinkholes,Obruk Plateau sinkholes,Seyithacı sinkholes,Siyeklik sinkholes and Basin sinkholes.The d/l ratios of each sinkhole group were separately determined and interpreted.Accordingly,most of the d/l ratios are smaller than 0.2.Namely,the long axes are higher than the depth and it indicates that the shallow and wide sinkholes are common in the region.It has been determined that the fracture systems in the region,as well as the lithology and groundwater factors,are quite effective in the formation and distribution of the sinkholes in the Karapınar region.Considering the distance of the sinkholes to the settlements,Seyithac?sinkholes are the most risky group in the region because they are deep and close to the settlements.
基金funded by the National Natural Science Foundation of China(Grant Nos.42241206,92058210,42074047,U2039203,42130306)。
文摘Recent geodetic and seismological observations of two major earthquakes in southeastern Türkiye in February 2023 have revealed complex rupture initiation,propagation,and segmentation along the East Anatolian Fault Zone(EAFZ)and surrounding regions.However,the role of upper crust structures along the EAFZ in determining the diverse rupture processes of this earthquake doublet remains unclear.To further investigate this,we employed double-difference location and seismic tomography techniques to determine high-resolution seismic velocities(V_(P),V_(S))and Poisson’s ratio(σ)structures using a multiparameter joint tomographic algorithm.Our dataset includes 100,833 high-quality source-receiver travel-time pairs of P-and Swaves.We find that the unique rupture processes of this earthquake doublet were primarily influenced by contrasting crustal seismic structures and localized geological settings.The M_(w)7.8 mainshock was initiated within a transitional edge zone characterized by a rigid part(asperity)of the seismogenic zone with sharp contrast variations in rock strength ranging from low to high along the EAFZ.In comparison,the M_(w)7.6 rupture originated in a ductile belt featuring fluid saturation with low-VP,low-VS,and high-σvalues that extended parallel to the Cardak Fault.The pronounced contrast structures observed along the former rupture can be attributed to the oblique collision system between the weakened section of the east Anatolian plateau and the brittle Arabian platform,while the latter rupture was initiated within the ductile structure associated with fluid intrusion caused by the northward subduction of the Cyprus slab and subsequent detachment.Furthermore,the occurrence of the first earthquake(E1)serves to alleviate shear stress on the second earthquake(E2)fault,potentially impeding the initiation of an E2 rupture.On the contrary,this event also significantly reduces the normal stress acting on the E2 fault due to a double left-lateral strike-slip system within a triangular region.This reduction not only results in a decrease of fault friction force and an increase in rock porosity but also induces lower strain drops and the redistribution of Coulomb stress,thereby contributing to the initiation of the E2 event.The proposed rupture pattern exceeds the conventional model that governs individual earthquake ruptures,offering new insights for mitigating potential seismic disasters in Türkiye.The lessons learned from this doublet event can contribute to reevaluating the ongoing risk of damaging earthquakes in China’s South-North Seismic Zone or other regions worldwide with comparable geological conditions.
