A debris flow,with terraced fields as the source area,broke out on June 25th,2018 in the Xiaotuga area of Yunnan Province,China,and this kind of debris flow is rarely recorded.Two purposes in this study:(1)the influen...A debris flow,with terraced fields as the source area,broke out on June 25th,2018 in the Xiaotuga area of Yunnan Province,China,and this kind of debris flow is rarely recorded.Two purposes in this study:(1)the influence of flow drag force on slope stability;(2)back-analyze the movement process of debris flow.First,the geological background and movement of this debris flow were described based on a field investigation.Then,drag force,calculated by the laminar flow theory,is added to the slope stability calculation model,which elaborates the initiation process of this disaster.Moreover,dynamic simulation software(DAN3D)was used to simulate the kinematic process of the debris flow with a variety of combination models.The study shows that the terrace area can quickly produce surface runoff and create a drag force under rainfall conditions,which is the essential reason for the initiation of debris flow.In addition,the use of the FVV(Frictional-Voellmy-Voellmy)model is found to provide the best performance in simulating this type of debris flow,which reveals that it lasts approximately 200 s and that the maximum velocity is 12 m/s.展开更多
Seismic intensity is critical for post-earthquake hazard assessment and response,but is often delayed because field surveys are required.Here,we propose a simple scheme for quick prediction of earthquake ground shakin...Seismic intensity is critical for post-earthquake hazard assessment and response,but is often delayed because field surveys are required.Here,we propose a simple scheme for quick prediction of earthquake ground shaking intensity using high-rate Global Navigation Satellite System(GNSS)data.In the scheme,high-rate GNSS displacement waveforms and static GNSS coseismic offsets are first used to invert the fault rupture process based on a one-fault model.The kinematic slip model is then employed as input for kinematic forward simulation to predict strong ground motion,which is subsequently convert into seismic intensities according to the China seismic intensity scale(GB/T 17742–2020).We take the 2021 Mw 7.3 Maduo Earthquake as a case study to illustrate the feasibility of this scheme.Our results show that the seismic intensity produced by the one-fault model is consistent with that from field investigations,especially in meizoseismal zones,suggesting that the scheme may serve as a potential solution for quick prediction of seismic intensity,which helps to disaster relief efforts after strong earthquakes.展开更多
基金supported by the National Natural Science Foundation of China(No.42077277)。
文摘A debris flow,with terraced fields as the source area,broke out on June 25th,2018 in the Xiaotuga area of Yunnan Province,China,and this kind of debris flow is rarely recorded.Two purposes in this study:(1)the influence of flow drag force on slope stability;(2)back-analyze the movement process of debris flow.First,the geological background and movement of this debris flow were described based on a field investigation.Then,drag force,calculated by the laminar flow theory,is added to the slope stability calculation model,which elaborates the initiation process of this disaster.Moreover,dynamic simulation software(DAN3D)was used to simulate the kinematic process of the debris flow with a variety of combination models.The study shows that the terrace area can quickly produce surface runoff and create a drag force under rainfall conditions,which is the essential reason for the initiation of debris flow.In addition,the use of the FVV(Frictional-Voellmy-Voellmy)model is found to provide the best performance in simulating this type of debris flow,which reveals that it lasts approximately 200 s and that the maximum velocity is 12 m/s.
基金supported by the Basic Scientific Funding of the Institute of Geology,China Earthquake Administration(No.IGCEA2120)the National Natural Science Foundation of China(Nos.U2139202 and 42104007)the Innovation Fund Project for College Teachers of Gansu Provincial Education Department(No.2025A-041)。
文摘Seismic intensity is critical for post-earthquake hazard assessment and response,but is often delayed because field surveys are required.Here,we propose a simple scheme for quick prediction of earthquake ground shaking intensity using high-rate Global Navigation Satellite System(GNSS)data.In the scheme,high-rate GNSS displacement waveforms and static GNSS coseismic offsets are first used to invert the fault rupture process based on a one-fault model.The kinematic slip model is then employed as input for kinematic forward simulation to predict strong ground motion,which is subsequently convert into seismic intensities according to the China seismic intensity scale(GB/T 17742–2020).We take the 2021 Mw 7.3 Maduo Earthquake as a case study to illustrate the feasibility of this scheme.Our results show that the seismic intensity produced by the one-fault model is consistent with that from field investigations,especially in meizoseismal zones,suggesting that the scheme may serve as a potential solution for quick prediction of seismic intensity,which helps to disaster relief efforts after strong earthquakes.
