Mount Semeru,an active volcano in East Java,Indonesia,erupted on December 4,2021,following extreme rainfall that caused an avalanche of hot pyroclastic flows and lava.The tropospheric conditions and dominant particle ...Mount Semeru,an active volcano in East Java,Indonesia,erupted on December 4,2021,following extreme rainfall that caused an avalanche of hot pyroclastic flows and lava.The tropospheric conditions and dominant particle components in the atmosphere can be monitored using Global Navigation Satellite System(GNSS)technology and remote sensing satellites.GNSS signal propagation delay in Precise Point Positioning(PPP)processing can be used to determine Zenith Tropospheric Delay(ZTD)and Precipitable Water Vapor(PWV)variables so that atmospheric conditions can be generated.In addition,by using remote sensing satellite data,it is possible to obtain rainfall data with high temporal resolution as well as the dominant particle and gas content values during eruptions.During the eruption period,the high value of PWV was dominated by the high intensity of precipitation during the rainy season.High rainfall before the eruption caused activity inside the mountain to increase,which occurred in avalanche type eruption.Apart from that,the atmosphere around Semeru was also dominated by SO_(2)content,which spreaded for tens of kilometers.SO_(2)content began to be detected significantly by remote sensing sensors on December 7,2021.In this study,deformation and atmospheric monitoring were also carried out using low-cost GNSS at the Semeru Monitoring Station on September 9-15,2022.The results of the ZTD and ZWD values show the dominance of the wet component,which is directly proportional to rainfall activity in this period.展开更多
Economic development, industrialization and dense population in Trabzon City have caused residential construction to increase by 300% in the last decade. The settlement area is moun- tainous and covered with heavy veg...Economic development, industrialization and dense population in Trabzon City have caused residential construction to increase by 300% in the last decade. The settlement area is moun- tainous and covered with heavy vegetation. Thus, the steep-sided topography and heavy precipita- tion means floods and landslides are common and in areas with little flat land. Since the mass movements in some parts of city create an enormous danger for buildings, site selection for residen- tial areas becomes increasingly important. This paper describes geotechnical and seismic properties of Tertiary volcanic rock and establishes the link between these units and construction. In this study, refraction tomography and multichannel analysis surface wave methods were applied in order to seek the best construction site in the residential area. The results of the geophysical study were com- pared with the borehole applications. A series of geomechnical tests were carried out on the core samples. Following that, statistical correlations were conducted by regression analysis to evaluate re- lationships between measured parameters. Rock Quality Designation and weathering degree were also determined. The methodology defined in this investigation proves to be an appropriate ap- proach to determine geotechnical properties of the foundation rocks and soils and a proper guide on future geotechnical studies for other cities.展开更多
In this study, the crust and upper mantle structure of Anatolia have been investigated by measuring the group velocity dispersion data of discriminated seismic surface waves. In the scope of the study, it has selected...In this study, the crust and upper mantle structure of Anatolia have been investigated by measuring the group velocity dispersion data of discriminated seismic surface waves. In the scope of the study, it has selected the profiles between six stations located in western Anatolia of Bogazici University Kandilli Observatory Earthquake Research Institute, national network of Turkey, and records of an earthquake (having about 10°epicentral distance) occurred in the eastern of Anatolia have been used. Firstly, surface wave discrimination filter based on the polarization properties has been applied tothree-component recordsand emphasized to surface waves. Then the group velocities have been calculated by multiple filter technique. A five-layered crustal model having total thickness of 38 - 40 km and Pn-wave velocity of 8.00 km/sec in the upper-mantle has been determined through inversion of surface wave group velocity dispersion data in the period range of 10 sec to 60 sec.展开更多
Vulnerability assessment and mapping play a crucial role in disaster risk reduction and planning for adaptation to a future earthquake.Turkey is one of the most at-risk countries for earthquake disasters worldwide.The...Vulnerability assessment and mapping play a crucial role in disaster risk reduction and planning for adaptation to a future earthquake.Turkey is one of the most at-risk countries for earthquake disasters worldwide.Therefore,it is imperative to develop effective earthquake vulnerability assessment and mapping at practically relevant scales.In this study,a holistic earthquake vulnerability index that addresses the multidimensional nature of earthquake vulnerability was constructed.With the aim of representing the vulnerability as a continuum across space,buildings were set as the smallest unit of analysis.The study area is in İzmit City of Turkey,with the exposed human and structural elements falling inside the most hazardous zone of seismicity.The index was represented by the building vulnerability,socioeconomic vulnerability,and vulnerability of the built environment.To minimize the subjectivity and uncertainty that the vulnerability indices based on expert knowledge are suffering from,an extension of the catastrophe progression method for the objective weighing of indicators was proposed.Earthquake vulnerability index and components were mapped,a local spatial autocorrelation metric was employed where the hotspot maps demarcated the earthquake vulnerability,and the study quantitatively revealed an estimate of people at risk.With its objectivity and straightforward implementation,the method can aid decision support for disaster risk reduction and emergency management.展开更多
基金the Indonesian Collaborative Research(RKI)2022:598/IT2/T/HK.00.01/2022Center of Volcanology and Geological Hazard Mitigation of Indonesia for the data and financial support of this research。
文摘Mount Semeru,an active volcano in East Java,Indonesia,erupted on December 4,2021,following extreme rainfall that caused an avalanche of hot pyroclastic flows and lava.The tropospheric conditions and dominant particle components in the atmosphere can be monitored using Global Navigation Satellite System(GNSS)technology and remote sensing satellites.GNSS signal propagation delay in Precise Point Positioning(PPP)processing can be used to determine Zenith Tropospheric Delay(ZTD)and Precipitable Water Vapor(PWV)variables so that atmospheric conditions can be generated.In addition,by using remote sensing satellite data,it is possible to obtain rainfall data with high temporal resolution as well as the dominant particle and gas content values during eruptions.During the eruption period,the high value of PWV was dominated by the high intensity of precipitation during the rainy season.High rainfall before the eruption caused activity inside the mountain to increase,which occurred in avalanche type eruption.Apart from that,the atmosphere around Semeru was also dominated by SO_(2)content,which spreaded for tens of kilometers.SO_(2)content began to be detected significantly by remote sensing sensors on December 7,2021.In this study,deformation and atmospheric monitoring were also carried out using low-cost GNSS at the Semeru Monitoring Station on September 9-15,2022.The results of the ZTD and ZWD values show the dominance of the wet component,which is directly proportional to rainfall activity in this period.
基金supported by Karadeniz Technical University, Scientific Research Funding (No. BTAP-695)
文摘Economic development, industrialization and dense population in Trabzon City have caused residential construction to increase by 300% in the last decade. The settlement area is moun- tainous and covered with heavy vegetation. Thus, the steep-sided topography and heavy precipita- tion means floods and landslides are common and in areas with little flat land. Since the mass movements in some parts of city create an enormous danger for buildings, site selection for residen- tial areas becomes increasingly important. This paper describes geotechnical and seismic properties of Tertiary volcanic rock and establishes the link between these units and construction. In this study, refraction tomography and multichannel analysis surface wave methods were applied in order to seek the best construction site in the residential area. The results of the geophysical study were com- pared with the borehole applications. A series of geomechnical tests were carried out on the core samples. Following that, statistical correlations were conducted by regression analysis to evaluate re- lationships between measured parameters. Rock Quality Designation and weathering degree were also determined. The methodology defined in this investigation proves to be an appropriate ap- proach to determine geotechnical properties of the foundation rocks and soils and a proper guide on future geotechnical studies for other cities.
文摘In this study, the crust and upper mantle structure of Anatolia have been investigated by measuring the group velocity dispersion data of discriminated seismic surface waves. In the scope of the study, it has selected the profiles between six stations located in western Anatolia of Bogazici University Kandilli Observatory Earthquake Research Institute, national network of Turkey, and records of an earthquake (having about 10°epicentral distance) occurred in the eastern of Anatolia have been used. Firstly, surface wave discrimination filter based on the polarization properties has been applied tothree-component recordsand emphasized to surface waves. Then the group velocities have been calculated by multiple filter technique. A five-layered crustal model having total thickness of 38 - 40 km and Pn-wave velocity of 8.00 km/sec in the upper-mantle has been determined through inversion of surface wave group velocity dispersion data in the period range of 10 sec to 60 sec.
基金supported by the Disaster and Emergency Management Presidency under Project No.AFAD-UDAP-Ç-19-06.
文摘Vulnerability assessment and mapping play a crucial role in disaster risk reduction and planning for adaptation to a future earthquake.Turkey is one of the most at-risk countries for earthquake disasters worldwide.Therefore,it is imperative to develop effective earthquake vulnerability assessment and mapping at practically relevant scales.In this study,a holistic earthquake vulnerability index that addresses the multidimensional nature of earthquake vulnerability was constructed.With the aim of representing the vulnerability as a continuum across space,buildings were set as the smallest unit of analysis.The study area is in İzmit City of Turkey,with the exposed human and structural elements falling inside the most hazardous zone of seismicity.The index was represented by the building vulnerability,socioeconomic vulnerability,and vulnerability of the built environment.To minimize the subjectivity and uncertainty that the vulnerability indices based on expert knowledge are suffering from,an extension of the catastrophe progression method for the objective weighing of indicators was proposed.Earthquake vulnerability index and components were mapped,a local spatial autocorrelation metric was employed where the hotspot maps demarcated the earthquake vulnerability,and the study quantitatively revealed an estimate of people at risk.With its objectivity and straightforward implementation,the method can aid decision support for disaster risk reduction and emergency management.
