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After the May 12 earthquake in Wenchuan, numerous debris flow disasters occurred due to heavy rainfall. After the earthquake, disaster prevention and mitigation projects, such as the sand dam, played an essential role in safety. However, when the outflow of solid material exceeds the designed storage capacity of the sand dam, the debris flow overtopping the dam intensifies the scraping effect on the source material of the gully channel. This paper takes the "8.20" debris flow in the Chutou gully as the research object. A transport mode of the debris flow after dam overtopping is studied through comprehensive field investigation, theoretical analysis, and indoor model tests. A quantitative evaluation model is established for the scraping depth and scraping volume of dam-overtopping debris flow. The study results showed that once the debris flow overtops a dam, the loose source carried by the channel is involved in the entire migration process, enlarging the fluid scale and intensifying the damage along the channel. The results agree with the measurements and observations, with maximum relative errors of 5.81% and 14.70%, respectively. This shows model validity. Furthermore, the test results show that the debris flow scarping phenomenon in the γ=[1.4 t/m3, 1.6 t/m3] interval is the most significant. Overall, this study will help improve future engineering decisions, design strategies, and finding the best design solutions to minimize the risk of dam-overtopping debris flow disasters. [ABSTRACT FROM AUTHOR]

On January 7, 2022, a Mw 6.6 earthquake occurred in Menyuan County, Qinghai Province, China. To understand the coseismic deformation mechanism of this earthquake, we utilized GNSS and InSAR geodetic observations to obtain the coseismic deformation field and inverted for the slip distributions of different fault models. Through a comparative analysis of the coseismic slip distribution characteristics of different fault models and fitting degree of observations, we proposed the relatively optimal fault model. The coseismic deformation results of two types of observations consistently show a dominant horizontal strike-slip motion for this earthquake. The deformation characteristics of the coseismic LOS displacement profile model, considering the fault dip angle and slip amount, indicate that the coseismic slip is concentrated in the shallow portion, with a maximum slip of 3.29 m at a depth of 1.31 km. The inversion results of the optimal fault model proposed in this study indicate that compared to the surface trace of the Lenglongling fault, the surface trace of the eastern section of the primary fault is deflected by 9.28°, with a length of approximately 14 km, and the western section extends westward approximately 9 km along the Lenglongling fault. In the strike-change area between the Lenglongling fault and the Tuolaishan fault, the secondary fault connects the primary fault and extends westward along the Tuolaishan fault for approximately 8 km. The primary fault corresponds to the Lenglongling fault, with a maximum slip of 4.28 m, and the secondary fault corresponds to the Tuolaishan fault, with a maximum slip of 2.44 m. [ABSTRACT FROM AUTHOR]

The Wenchuan earthquake strongly disturbed the earth surface and induced sufficient loose debris in the mountain basin, which supplies sufficient solid materials for debris flow initiation. Recently, a catastrophic debris flow was induced by strong rainfall on June 26, 2023 in the Banzi basin. Inconsistent with the first few years of the Wenchuan earthquake, the hillslope landslide sediment supply for debris flow occurrence is limited after 15 years of the Wenchuan earthquake, and the materials supplied for debris flow in the later period are mainly obtained from alluvium deposited along the channel. Simultaneously, this debris flow was triggered by flash flood through strongly erosion channel materials. However, although 15 years have passed since the Wenchuan earthquake, the triggering rainfall conditions have still not returned to pre-earthquake level. This debris flow first initiated in the upper branches of the basin and then gradually transported downstream at an average discharge of 806.99 m3/s, and approximately 82.80 × 104 m3 solid materials were transported out the Banzi basin to form a debris flow fan with length of 120 m and width of 260 m in the Minjiang River, which poses a serious threat to the resettled population and destroy the reconstruction infrastructures. Importantly, there are still sufficient solid materials deposited in the basin, this could result in debris flow activity continuing for an unpredictable time. Therefore, implementation early warning, prevention, and mitigation measures in this basin are still important for debris flow disaster management in the later period of Wenchuan earthquake. [ABSTRACT FROM AUTHOR]

Large amounts of co-seismic landslides provide abundant debris sources following a strong earthquake and are prone to initiate and generate debris flow under heavy rainfall. Assessing the susceptibility they pose and what drives their movement in the years following the mainshock has not yet been attempted, primarily because multitemporal debris flow inventories are lacking. This study conducted statistical analyses using the multitemporal debris flow inventory (2008–2021) following the 2008 Wenchuan earthquake and a set of conditional factors (debris source, terrain, and hydrology). The dynamic susceptibility evaluation model was created using logistic regression. The temporal evolution of these factors affecting debris flow runout was explained. Our findings suggest that topography variables grew rapidly after the earthquake, while debris source factors dominated for seven years after the disaster before declining progressively to zero. These findings may have significant consequences for traditional susceptibility assessment models in regions where co-seismic landslides are the dominant debris flow source. [ABSTRACT FROM AUTHOR]

The suddenness and destructive power of earthquake disasters pose significant threats to ecosystems. Understanding the changes in post‐earthquake ecosystem services and the complex relationships of their trade‐offs and synergistic effects is crucial for post‐disaster recovery and achieving a holistic and sustainable balance of human well‐being. However, quantifying post‐disaster ecosystem services and these intricate relationships, as well as probing the mechanisms behind their formation from a spatial perspective, remain challenging. This study presents a comprehensive framework that integrates spatial statistical methods, the InVEST model, geodetectors, and the Multiscale Geographically Weighted Regression model (MGWR) to quantify trade‐offs and synergistic effects among ecosystem services before and after earthquakes, and to investigate the spatial heterogeneity of these relationship effects with various driving factors. Results indicate (1) Typical ecosystem services, that is, water yield, soil conservation, carbon storage, and habitat quality, have more weak trade‐off effects and fewer synergistic effects. These relationship intensities vary considerably spatially, demonstrating some agglomerative distribution, suggesting that the ecosystem has not yet recovered to a good state after the quake; (2) The impact of different factors on the trade‐offs and synergies between ecosystem services varies. Interaction effects of driving factors are stronger than singular effects. Relationships between soil conservation and other ecosystem services are primarily influenced by topography and climate. Relationships involving carbon storage are mainly affected by vegetation and climate, while those concerning habitat quality are attributed mostly to human and climatic factors; (3) In the modeling process, considering the different spatial scales of driving factors, MGWR outperforms the Geographically Weighted Regression in explaining the relationship between ecosystem services and driving factors. Moreover, several spatially feasible and targeted ecological measures are proposed to enhance the synergy among ecosystem services. By focusing on the changes in ecosystem services, this study reveals the intrinsic mechanisms of trade‐offs and synergies between ecosystem services, offering insights for related studies in other regions. [ABSTRACT FROM AUTHOR]

In response to escalating global climate change and its increasing impacts worldwide, this study investigates the consequences of extreme weather events, focusing on the unprecedented 2022 monsoon season in the Swat River basin of Pakistan. Record-breaking rainfall, exceeding the 1960–2021 averages by 7–8 %, triggered catastrophic debris flows and floods, aggravating low-income communities' challenges. The resulting financial instability severely affected millions, causing extensive damage to homes, crops, and transportation. The study employs a multidisciplinary approach, combining field investigations, remote sensing data interpretation, and numerical simulations to identify the factors contributing to debris flow incidents. Analysis of land cover changes reveals a decrease in grasslands and an increase in barren land, indicating the adverse effects of deforestation on the region. Topography and gully morphology are crucial in initiating debris flows, with steep gradients and shallow slope failures predominant. Numerical simulations show that debris flows reached high velocities of 18 m/s and depths of 40 m within 45 minutes. Two debris flows resulted in the formation of dams along the Swat River, intensifying subsequent floods. The study emphasizes the interplay of extreme rainfall and deforestation during the rainy season, rendering the region susceptible to debris flows and hindering restoration efforts. The findings underscore the urgent need for comprehensive disaster mitigation strategies. Recommendations include climate change mitigation, reforestation initiatives, and discouraging construction activities in flood-prone and debris flow-prone regions. The study advocates for enhanced early warning systems and rigorous land use planning to protect the environment and local communities, highlighting the imperative of proactive measures in the face of escalating climate challenges. Additionally, the study investigates the spatial distribution of various events and their consequences, including potential hydro-meteorological triggers, and how such events initiate processes that change mountain landscapes. It also assesses the degree to which the 2022 monsoon can be classified as abnormal. The combination of empirical evidence and practical insights presented in this study highlights research gaps and proposes routes toward attaining a comprehensive comprehension of monsoon-triggered geological hazards and consequences. [ABSTRACT FROM AUTHOR]

Compelling evidence has shown that geomagnetic disturbances in vertical intensity polarization before great earthquakes are promising precursors across diverse rupture conditions. However, the geomagnetic vertical intensity polarization method uses the spectrum of smooth signals, and the anomalous waveforms of seismic electromagnetic radiation, which are basically nonstationary, have not been adequately considered. By combining pulse amplitude analysis and an experimental study of the cumulative frequency of anomalies, we found that the pulse amplitudes before the 2022 Luding M6.8 earthquake show characteristics of multiple synchronous anomalies, with the highest (or higher) values occurring during the analyzed period. Similar synchronous anomalies were observed before the 2021 Yangbi M6.4 earthquake, the 2022 Lushan M6.1 earthquake and the 2022 Malcolm M6.0 earthquake, and these anomalies indicate migration from the periphery toward the epicenters over time. The synchronous changes are in line with the recognition of previous geomagnetic anomalies with characteristics of high values before an earthquake and gradual recovery after the earthquake. Our study suggests that the pulse amplitude is effective for extracting anomalies in geomagnetic vertical intensity polarization, especially in the presence of nonstationary signals when utilizing observations from multiple station arrays. Our findings highlight the importance of incorporating pulse amplitude analysis into earthquake prediction research on geomagnetic disturbances. [ABSTRACT FROM AUTHOR]

This paper analyzed the strong motion characteristics based on 86 three-component strong motion records of the MW 6.6 Luding earthquake. Additionally, the factors that influence the variation in ground motion for three earthquakes with similar magnitude in Sichuan Province were investigated. The analysis result indicates a strong correlation between the observed ground motion parameters and the distribution of published Modified Mercalli Intensity. The residual analysis reveals that the spectral accelerations at periods 0.1–10.0 s are amplified to 0.0798–0.3057 times the mean level in the rupture forward direction and weakened to 0.0738–0.2831 times the mean level in the rupture backward direction. The maximum pulse direction recorded by the 51LDJ station is N6°E, aligning with the vertical fault direction. The velocity pulses has distinct bidirectional pulses in the waveforms, with a PGV of 37.0 cm/s. The source effect of the strike-slip MW 6.6 Luding and MW 6.5 Jiuzhaigou earthquakes on ground motion is relatively less significant compared to the average level of mainshocks in southwest China. However, the thrust-fault MW 6.7 Lushan earthquake exhibits a stronger source effect on ground motion during short and medium periods, but a weaker source effect during long periods when compared to the average level. The anelastic attenuation of the Longmenshan, Xianshuihe, and Huya fault zones in Sichuan exhibits significant regional variation and periodic correlation. This phenomenon is closely linked to the regional tectonic background variations and the heterogeneity of crustal structure within the area. [ABSTRACT FROM AUTHOR]

The interplay between insomnia and PTSD symptoms remains misunderstood, and seems to be influenced by other factors like individual resilience. Our study examined the moderating role of resilience in the relationship between insomnia and PTSD symptoms among a sample of Lebanese adolescents, in the aftermath of the 2023 earthquake. This cross sectional study, conducted in April, 2 months after the earthquake, enrolled 546 Lebanese adolescents. We used the Sleep Self Report, the Resilience Scale for Adolescents and the 13-item Children’s Impact of Event Scale. The interaction insomnia severity by resilience was significantly associated with PTSD scores. At low, moderate and high resilience levels, higher insomnia severity was significantly associated with lower PTSD. Resilience moderated the relationship between insomnia and PTSD, mitigating the detrimental impact of disrupted sleep on PTSD symptoms. This data can guide healthcare administrators and psychiatric caregivers in classifying risk factors and implementing interventions to predict PTSD development. [ABSTRACT FROM AUTHOR]

Debris flows can develop into mega catastrophes in semi-arid regions when the source materials come from landslides, and both snowmelt and precipitation are involved in increasing water discharge. In such environments, the formation of large-scale debris flows exhibits a distinguishable pattern, in which a multi-fold lower triggering rainfall threshold holds compared to humid regions. Previous research mainly focuses on mechanisms in humid environments or neglects variations across aridity classes. In this study, the formation and evolutionary mechanism of a debris flow occurring in a semi-arid context is investigated via field surveys, granularity measurement, terrain and climate analyses, and snow cover change detection. By examining the July 22, 2021, Xiao Dongsuo debris flow at Amidongsuo Park in the Qilian Ranges on the northeastern margin of the Tibetan Plateau, the mechanism of debris flows in semi-arid regions is revealed. The research finds that the large debris flow, whose course erosion scales up the disaster by 0.12 million m3, is primarily supplied by landslide deposits of 1.16 million m3. The debris flow is empowered by the integrated flow of extreme precipitation and extreme heat-stimulated snowmelt. However, the precipitation required to trigger the debris flow is much lower than that of precipitation-dominated ones and those in humid regions. In semi-arid mountains, prolonged extreme heat tends to increase soil moisture in areas covered by snow or permafrost. This reduces slope stability and induces slope failures, amplifying the disaster magnitude and raising disaster risks through extended deterioration. Hence, this study inspects the failure mechanism associated with debris flows in semi-arid regions for a more comprehensive understanding to constitute viable control plans for analogous disasters. [ABSTRACT FROM AUTHOR]

As wildfire increases in the western United States, so do postfire debris-flow hazards. The U.S. Geological Survey (USGS) has developed two separate models to estimate (1) rainfall intensity thresholds for postfire debris-flow initiation and (2) debris-flow volumes. However, the information necessary to test the accuracy of these models is seldom available. Here, we studied how well these models performed over a 2-year period in the 2020 Grizzly Creek Fire burn perimeter in Glenwood Canyon, Colorado, USA, through the development of a debris-flow response inventory. The study area had the advantage of a network of 11 rain gauges for rainfall intensity measurements and repeat lidar data for volume estimates. Our observations showed that 89 % of observed debris flows in the first year postfire were triggered by rainfall rates higher than the fire-wide rainfall threshold produced by the current USGS operational model (M1). No debris flows were observed in the second year postfire, despite eight rainstorms with intensities higher than the modeled rainfall threshold. We found that the operational model for debris-flow initiation rainfall thresholds works well in this region during the first year but may be too conservative in year 2 due to vegetation recovery and sediment depletion. However, rainfall thresholds in the second year can be improved by using updated remote sensing imagery to recalculate the debris-flow initiation likelihood with the M1 model. The current volume model overestimates for this region by a median value of 4.4 times. However, the offset between the model estimates and observations is approximately linear, and the volumes from the Grizzly Creek debris flows had a similar magnitude to historic postfire debris flows in the region. Consequently, the current volume model could be adjusted with a regional correction factor. [ABSTRACT FROM AUTHOR]

On 5 September 2022 (BJT), Luding, located in southwestern Sichuan Province, China, experienced an MS 6.8 earthquake. This earthquake occurred within the historical rupture zone of the 1786 MS 7.75 event, part of the southern section of the Xianshui He Fault belt. Given the average 155-year recurrence interval for strong earthquakes in this area, the 236 years since the last event made this earthquake somewhat expected. However, prior to this event, we did not detect any anomalies indicating low surface b-values, which are often indicative of a high-stress state in the source area before strong earthquakes, as highlighted by numerous studies. Our research focused on the northern section of the eastern boundary of the Sichuan–Yunnan sub-block, encompassing the Xianshui He, Anning He, Zemu He, and Daliang Shan fault belts. We meticulously located earthquakes of ML ≥ 1.5 from 2009 to May 2022. The catalog was divided into two periods: 2009–2014 and 2015–May 2022. Using an AIC-constraint method, we analyzed the changes in b-values (Δb) in the latter period compared to the former. Our findings revealed a significant abnormal Δb zone (Δb < −0.3), with a radius of approximately 50 km, when ΔAIC ≥ 2 was selected. Intriguingly, the epicenter of the recent Luding MS 6.8 earthquake fell within this abnormal zone. Furthermore, we calculated the b-value cross-section for the southern section of the Xianshui He fault belt using a directory of precisely located small earthquakes. This revealed that the location, scale, and shape of the abnormally low-b-value area corresponded with the large displacement co-seismic area of the main earthquake, affirming the b-value's effectiveness in identifying asperities. The b-value's temporal evolution prior to the mainshock exhibited a nearly decade-long continuous decrease, signifying a long-term stress-loading process akin to that observed before many strong earthquakes. The b-value anomalies observed from different profiles before the Luding earthquake underline the necessity of a comprehensive, multi-dimensional analysis of such anomalies. Finally, our analysis indicates that nine earthquakes with MS ≥ 6.5, including the Luding MS 6.8 event, have contributed to increased Coulomb Failure Stress change (ΔCFS) in the Daofu (DF)–Kangding (KD) section of the Xianshui He fault belt and the northern section of the Anning He fault belt south of Shimian (SM), with amplitudes surpassing the 0.01 MPa threshold. This suggests the potential for strong earthquakes in these zones. [ABSTRACT FROM AUTHOR]

[Objective] This study aims to reveal the distribution patterns and characteristics of co-seismic geological hazards in earthquake swarms, clarify the differences in induced geological hazards by different types of earthquakes, further understand the seismic risks around and within the Bayan Har Block, and provide efficient guidance for the prediction and prevention of secondary geological hazards induced by earthquakes. [Methods] We take the co-seismic geological hazards of the Maerkang Ms 6.0 earthquake swarm in 2022 as the research focus. Through systematic data and results analysis on earthquake swarm sequence, regional tectonic environment, regional crustal deformation, and post- earthquake short-term geological hazard, the regional and deep structural environment of the Maerkang Ms 6.0 earthquake swarm and the main controlling factors of co-seismic geological hazards are revealed. [Results] The results show that the Maerkang Ms 6.0 earthquake swarm is a deep-seated sticky-slip earthquake that occurred on a secondary fault in the active strong earthquake zone within the Bayan Har block, a region with extremely strong peripheral boundary activity. The earthquakes with similar magnitudes may be the result of ruptures of secondary faults of the Songgang fault and the successive ruptures of the barriers between them. The earthquake has resulted in 83 newly discovered geological hazard risks, exacerbating deformation in 106 existing hazard spots and triggering multiple high-altitude landslides and a series of fractured mountain slopes. The areas of extreme, high, and medium geological hazard risk in Caodeng Town, the epicenter area after the earthquake, account for 1.62%, 4.80%, and 12.37%, respectively. The occurrence of secondary geological hazards following earthquakes exhibits a positive correlation with the earthquake magnitude, with the number increasing linearly as the magnitude rises. [Conclusion] The significant differences in the GPS horizontal velocity field and vertical velocity field on both sides of the Darlag-Songgang-Fubianhe fault zone are key factors contributing to the activity of this fault and triggering the recent earthquake. The main controlling factors of co-seismic geological hazards induced by earthquakes are, from primary to secondary, the ruptured fault and its associated faults, seismic magnitude and energy attenuation, terrain slope and altitude difference, and rock mass structure and density of structural surfaces. [Significance] This study predicts a high risk of future strong earthquakes in the intersection area of the Songgang fault, which triggered this earthquake, and the Longriba active fault. The surrounding area of the seismogenic fault and its associated faults are at a high risk of geological hazards during earthquakes. The findings provides a reference for predicting and controlling the risk of co-seismic geological hazards in this area. [ABSTRACT FROM AUTHOR]

A larger antecedent effective precipitation (AEP) indicates a higher probability of a debris flow (Pdf) being triggered by subsequent rainfall. Scientific topics surrounding this qualitative conclusion that can be raised include what kinds of variation rules they follow and whether there is a boundary limit. To answer these questions, Jiangjia Gully in Dongchuan, Yunnan Province, China, is chosen as the study area, and numerical calculation, a rainfall scenario simulation, and the Monte Carlo integration method have been used to calculate the occurrence probability of debris flow under different AEP conditions and derive the functional relationship between Pdf and AEP. The relationship between Pdf and AEP can be quantified by a piecewise function. Pdf is equal to 15.88 %, even when AEP reaches 85 mm, indicating that debris flow by nature has an extremely small probability compared to the rainfall frequency. Data from 1094 rainfall events and 37 historical debris flow events are collected to verify the reasonability of the functional relationship. The results indicate that the piecewise functions are highly correlated with the observation results. Our study confirms the correctness of the qualitative description of the relationship between AEP and Pdf , clarifies that debris flow is a small-probability event compared to rainfall frequency, and quantitatively reveals the evolution law of debris flow occurrence probability with AEP. All the above discoveries can provide a clear reference for the early warning of debris flows. [ABSTRACT FROM AUTHOR]

This article explores the concept of being "on-site" in the context of South Korean democracy movements. It discusses how being present in public spaces and witnessing marginalized places became a quality used to evaluate political strategies and literary works. The article includes examples of on-site struggles in the era of infrastructural capitalism, such as aesthetic movements, experimental music, and cinematic techniques. It also emphasizes the importance of paying attention to absences and silences in historical narratives and explores the destabilization of national identities through global cultural exchanges. The text further discusses topics related to cultural movements, capitalism, and ecological issues, including the rise of infrastructural capitalism in China, challenges faced by communities after disasters, and the importance of place making in rebuilding. It also analyzes a film that addresses ecological visibility and offers alternative perspectives on life and death. Overall, the text highlights the significance of on-sitedness and local experiences in understanding and addressing these complex issues. [Extracted from the article]

Understanding the spatial heterogeneity of debris-flow-prone areas holds significant implications for regional risk management, particularly in seismically active regions with geological faults. Despite the significance of this knowledge, a comprehensive quantification of the influence of regional topographical and geological factors on the spatial heterogeneity of debris-flow-prone areas has been lacking. This study selected the Hengduan Mountains, an earthquake-prone region characterized by diverse surface conditions and complex landforms, as a representative study area. An improved units zoning and objective factors identification methodology was employed in earthquake and fault analysis to assess the impact of seismic activity and geological factors on spatial heterogeneity of debris-flow prone areas. Results showed that the application of GIS technology with hydrodynamic intensity and geographical units analysis can effectively analyze debris-flow prone areas. Meanwhile, earthquake and fault zones obviously increase the density of debris-flow prone catchments and make them unevenly distributed. The number of debris-flow prone areas shows a nonlinear variation with the gradual increase of geomorphic factor value. Specifically, the area with 1000 m–2500 m elevation difference, 25°–30° average slope, and 0.13–0.15 land use index is the most favorable conditions for debris-flow occurrence; The average annual rainfall from 600 to 1150 mm and landslides gradient from 16° to 35° are the main causal factors to trigger debris flow. Our study sheds light on the quantification of spatial heterogeneity in debris flow-prone areas in earthquake-prone regions, which can offer crucial support for post-debris flow risk management strategies. [ABSTRACT FROM AUTHOR]

The spatial accessibility of emergency shelters, indicating the difficulty of evacuation and rescue, is crucial for disaster mitigation and emergency management. To analyze accessibility, an effective approach is to evaluate the service capacity of emergency shelters. Multifaceted factors were employed to enhance the quantitative accuracy of accessibility indicators. However, scenario-specific analysis has not been emphasized. Considering the devastating potential of great earthquake disasters, we cannot ignore the impact of these scenarios on emergency shelter accessibility, especially in areas with high seismic risk. In this study, we developed an earthquake scenario-specific framework for spatial accessibility analysis (SAA), which integrates the service capacity of emergency shelters and the impact of strong ground motion and fault rupturing. We applied this framework to the urban area of Xichang City in Sichuan Province, western China. Xichang City, located in the linked area of the Anninghe fault and Zemuhe fault with many extreme historical earthquake disaster records, is prone to high seismic risk. We firstly collected emergency shelter and road network data in Xichang City. We then applied SAA based on the road network, using the network analysis method. After that, we analyzed the impact of strong ground motion on accessibility and generated the setback zone of fault rupturing. We integrated the effect of strong ground motion on accessibility within the setback zone of active faults. Finally, we generated a comprehensive accessibility map, considering both the predicted strong ground motion and potential fault rupturing. Our results show that the accessibility level changed in several towns of urban Xichang City due to strong ground motion and fault rupturing. The accessibility level decreased in Lizhou, Xingsheng, and Anning Towns. For areas with mapped fault lines, the accessibility level is Very-Low. Our results demonstrate the impact of earthquake damage on the accessibility of emergency shelters and the complexity of evacuation in earthquake scenarios. In general, we added earthquake rupturing and ground motion characteristics into the SAA framework. This framework will help us enhance the reliability of SAA and the feasibility of seismic vulnerability evaluation. [ABSTRACT FROM AUTHOR]

Debris flow is a sudden natural disaster in mountainous areas, which seriously threatens the lives and property of nearby residents. Therefore, it is necessary to predict the volume of debris flow accurately and reliably. However, the predictions of back propagation neural networks are unstable and inaccurate due to the limited dataset. In this study, the Cubic map optimizes the initial population position of the whale optimization algorithm. Meanwhile, the adaptive weight adjustment strategy optimizes the weight value in the shrink-wrapping mechanism of the whale optimization algorithm. Then, the improved whale optimization algorithm optimizes the final weights and thresholds in the back propagation neural network. Finally, to verify the performance of the final model, sixty debris flow gullies caused by earthquakes in Longmenshan area are selected as the research objects. Through correlation analysis, 4 main factors affecting the volume of debris flow are determined and inputted into the model for training and prediction. Four methods (support vector machine regression, XGBoost, back propagation neural network optimized by artificial bee colony algorithm, back propagation neural network optimized by grey wolf optimization algorithm) are used to compare the prediction performance and reliability. The results indicate that loose sediments from co-seismic landslides are the most important factor influencing the flow of debris flows in the earthquake area. The mean absolute percentage error, mean absolute error and R2 of the final model are 0.193, 29.197 × 104 m3 and 0.912, respectively. The final model is more accurate and stable when the dataset is insufficient and under complexity. This is attributed to the optimization of WOA by Cubic map and adaptive weight adjustment. In general, the model of this paper can provide reference for debris flow prevention and machine learning algorithms. [ABSTRACT FROM AUTHOR]

Geometric complexities play an important role in the nucleation, propagation, and termination of strike-slip earthquake ruptures. The 2021 Mw7.4 Maduo earthquake rupture initiated at a large releasing stepover with a complex fault intersection. In the epicentral region, we conducted detailed mapping and classification of the surface ruptures and slip measurements associated with the earthquake, combining high-resolution uncrewed aerial vehicle (UAV) images and optical image correlation with field investigations. Our findings indicate that the coseismic ruptures present discontinuous patterns mixed with numerous lateral spreadings due to strong ground shaking. The discontinuous surface ruptures are uncharacteristic in slip to account for the large and clear displacements of offset landforms in the epicentral region. Within the releasing stepovers, the deformation zone revealed from the optical image correlation map indicates that a fault may cut diagonally across the pull-apart basin at depth. The left-lateral horizontal coseismic displacements from field measurements are typically ≤0.6 m, significantly lower than the 1–2.7 m measured from the optical image correlation map. Such a discrepancy indicates a significant proportion of off-fault deformation or the possibility that the rupture stopped at a shallow depth during its initiation phase instead of extending to the surface. The fault network and multi-fault junctions west and south of the epicenter suggest a possible complex path, which retarded the westward propagation at the initial phase of rupture growth. A hampered initiation might enhance the seismic ground motion and the complex ground deformation features at the surface, including widespread shaking-related fissures. [ABSTRACT FROM AUTHOR]

The seismic risk and vulnerability of urban building clusters are fundamental indicators for quantifying urban seismic resilience. The empirical vulnerability and risk models developed using various risk probability assessment theories and real seismic loss observation data from typical building clusters can provide positive references for predicting and evaluating urban earthquake resilience. However, the data used to validate and optimize the vulnerability and resilience models of building portfolios are mostly discrete points within a city. The coupling effect of multiple intensity measures is rarely considered, resulting in a relatively low evaluation accuracy of the established seismic hazard model. This study considers the comprehensive impact of macroseismic and instrumental intensity on the vulnerability of typical urban building portfolios. A multidimensional parameter seismic risk and vulnerability model considering updated damage states is proposed. Based on field inspection data from the 2008 Wenchuan earthquake in China, an optimized hazard and vulnerability model considering all the buildings (8669 buildings) in Dujiangyan city was developed. An innovative structural vulnerability membership index was proposed to estimate the correlation between typical damage states, and vulnerability correlation parameter models were developed. An improved nonlinear vulnerability regression model considering hybrid intensity measures was proposed, and vulnerability comparison curves and matrices were generated considering the empirical damage data of buildings in Dujiangyan city. An optimized seismic damage index calculation model was developed considering five typical building portfolios in Dujiangyan city. [ABSTRACT FROM AUTHOR]

The study of seismic ruptures is crucial for understanding major earthquake events. Historically, research on large earthquake rupture processes has required a long time to be published. However, recent advancements in earthquake early warning (EEW) systems have allowed for more rapid analyses of earthquake rupture inversions. The widespread and dense distribution of EEW stations provides in China an opportunity to study and invert rupture processes in near-real time. Two notable earthquakes were studied using this technology: the 2017 Jiuzhaigou MW 6.5 earthquake in Sichuan Province, China, and the 2022 Menyuan MW 6.7 earthquake in Qinghai Province, China. In both instances, numerous strong-motion sensors captured the seismic events and transmitted waveform data to data analysis centers in real time. Following automated site selection and preparation procedures, the rupture processes of these earthquakes were analyzed and released within 30 min of the event origin. This rapid response time demonstrates that the seismic rupture process determined through inversion using existing EEW systems can serve as a guide for emergency rescue work after earthquakes. [ABSTRACT FROM AUTHOR]

The critical rainfall of runoff-initiated debris flows is utmost importance for local early hazard forecasting. This paper presents research on the critical rainfall of runoff-initiated debris flows through comparisons between slope gradients and three key factors, including topographic contributing area, dimensionless discharge, and Shields stress. The rainfall amount was estimated by utilizing in-situ rainfall records and a slope-dependent Shields stress model was created. The created model can predict critical Shields stress more accurately than the other two models. Furthermore, a new dimensionless discharge equation was proposed based on the corresponding discharge-gradient datasets. The new equation, along with factors such as contributing area above bed failure sites, channel width, and mean diameter of debris flow deposits, predicts a smaller rainfall amount than the in-situ measured records. Although the slope-dependent Shields stress model performs well and the estimated rainfall amount is lower than the in-situ records, the sediment initiation in the experiments falls within sheet flow regime due to a large Shields stress. Therefore, further sediment initiation experiments at a steeper slope range are expected in the future to ensure that the sediment transport belongs to mass failure regime characterized by a low level of Shields stress. Finally, a more accurate hazard forecast on the runoff-initiated debris flow holds promise when the corresponding critical slope-dependent dimensionless discharge of no motion, fluvial sediment transport, mass flow regime, and sheet flow regime are considered. [ABSTRACT FROM AUTHOR]

To learn the process of urban land evolution before and after an earthquake is vital to formulate the urban reconstruction control policies and recovery measures in the earthquake-stricken areas. However, spatiotemporal evolution and its driving factors of urban land in earthquake-prone areas remains limited due to the scarcity of ground observation data. This research, leveraging night-time light remote sensing imagery and land cover data, conducted a comprehensive analysis of the long-term evolution characteristics of urban land in earthquake-prone areas. It introduced methodologies for assessing the socio-economic impact and the primary natural environmental factors driving urban land evolution in these regions. To validate the proposed methods, the 2008 Wenchuan earthquake-affected area in China was selected as a representative study area. The results indicated that the average Digital Number (DN) values in socio-economically impacted areas showed a trend of rising, falling, and then rising again after the earthquake. DN values in three types of damaged areas including Type II,Type III, and Type IV exceeded pre-earthquake levels. The analysis of determinative factors influencing urban land evolution revealed that slope and elevation were key elements in controlling urban land expansion before the earthquake, whereas factors such as slope, elevation, lithology, and faults had a stronger influence on urban land expansion after the earthquake. It can be seen that, in view of the differences in the natural conditions of regions for post-disaster reconstruction, the local government need to actively adjust and adapt to urban spatial planning, so as to leverage the scale effect of large-scale inputs of funds, facilities, human resources and other factors after the disaster, thus enhancing resilience and recovery efficiency in response to disaster impacts. [ABSTRACT FROM AUTHOR]

The development of machine learning technology enables more robust real-time earthquake monitoring through automated implementations. However, the application of machine learning to earthquake location problems faces challenges in regions with limited available training data. To address the issues of sparse event distribution and inaccurate ground truth in historical seismic datasets, we expand the training dataset by using a large number of synthetic envelopes that closely resemble real data and build an earthquake location model named ENVloc. We propose an envelope-based machine learning workflow for simultaneously determining earthquake location and origin time. The method eliminates the need for phase picking and avoids the accumulation of location errors resulting from inaccurate picking results. In practical application, ENVloc is applied to several data intercepted at different starting points. We take the starting point of the time window corresponding to the highest prediction probability value as the origin time and save the predicted result as the earthquake location. We apply ENVloc to observed data acquired in the southern Sichuan Basin, China, between September 2018 and March 2019. The results show that the average difference with the catalog in latitude, longitude, depth, and origin time is 0.02°, 0.02°, 2 km, and 1.25 s, respectively. These suggest that our envelope-based method provides an efficient and robust way to locate earthquakes without phase picking, and can be used in earthquake monitoring in near-real time. [ABSTRACT FROM AUTHOR]

With the increase in both rainfall and intensity due to climate change, the risk of debris flows is also increasing. In Korea, the increasing damage caused by debris flows has become a social issue, and research on debris-flow response is becoming increasingly important. Understanding the rainfall that induces debris flows is crucial for debris-flow response, and methods such as the I-D method have been used to evaluate and predict the risk of debris flows. However, previous studies on debris flow-induced rainfall analysis have been limited by the subjective decision of the researcher to select the impact meteorological stations, which greatly affects reliability. In this paper, in order to establish an objective standard, various maximum allowable distances between debris-flow disaster areas and meteorological stations were adjusted to 1, 3, 5, 7, 9, 11, 13, and 15 km using the CTRL-T automatic calculation algorithm, and the optimal maximum allowable distance suitable for Korean terrain was derived through parameter sensitivity analysis. Based on this, we developed a nomogram for sediment disaster risk prediction and warning in Gangwon-do, and applied it to past disaster cases, and found that, although the prediction time for each stage varies depending on the maximum allowable distance, on average, it is possible to predict the risk of sediment flows 4 to 5 h in advance. It is believed that the results of this study can be used to reduce sediment flow damage in advance. [ABSTRACT FROM AUTHOR]

Seismic attenuation is a fundamental property of the Earth's media. Attenuation structure for the complicated geological structures with strong seismicity in the Sichuan-Yunnan region is poorly studied. In this study, we collected 108,399 waveforms of 11,517 local small earthquakes with magnitudes between 1.5 and 3.5 from January 2014 to September 2021 in the Sichuan-Yunnan region and its adjacent areas. We employed an envelope inversion technique for separating the intrinsic and scattering attenuations of the S coda wave, and obtained the intrinsic and scattering attenuation structures for frequencies between 0.25 and 8.00 Hz. The attenuation structures correlate well with the geological units, and some major faults mark the attenuation variations where historic large earthquakes have occurred. The regional average attenuation shows a negative frequency dependence. The average scattering attenuation has a faster descending rate than the average intrinsic attenuation, and is dominant at low frequencies, while at high frequencies the average intrinsic attenuation is stronger. The lateral variation in the intrinsic attenuation is consistent with the variation in heat flow, the scattering attenuation may be related to the scatter distribution and size. The total attenuation is consistent with the previous studies in this region, and the separate intrinsic and scattering attenuation may be useful in understanding regional tectonics and important in earthquake prevention and disaster reduction. [ABSTRACT FROM AUTHOR]

Canada's new membership to the International Remembrance Alliance in 2009 bore the anticipation of Canada's commitment against racism of any kind. In this context, I review Holocaust representation in an Ontario Grade Ten course curriculum, 'Canadian and World History 10', and its provincially advised textbook, Canadian Sources: Investigated (1914 to the Present) (2008). I critique three main aspects of the portrayal: an ambiguously framed introductory paragraph which may harvest Hitler-centric misconceptions, antisemitism in Canada is presented via various opposing perspectives which obscure a clear image of the term, and an inadequate definition of the term 'Holocaust'. [ABSTRACT FROM AUTHOR]

The potential risks associated with debris flows have significantly increased due to changes in global climate, population growth, and economic development. Despite the high susceptibility of debris flows in the Wenchuan earthquake-affected area, few studies have focused on quantitative risk assessment methods for debris flows. To overcome this shortcoming, we proposed an integrated approach by using a probability-based model and numerical simulations to quantify the expected direct economic losses of buildings for debris flows under multiple rainfall intensity scenarios. First, we simulated the hazard processes of debris flows with recurrence periods of 20, 50, 100, and 200 years and obtained the distribution of debris flow intensities defined by the momentum flux. Then, we assessed the direct economic losses for each building related to different recurrence periods based on fragility curves and debris flow intensity maps. The results show that the risk loss of different hazard scenarios increases dramatically with an increase in debris flow magnitude. This methodology provides visual and quantitative risk assessment for specific buildings affected by debris flows, enabling authorities and decision-makers to reduce risk and optimize risk management strategies. It is a rapid and effective way to assess the capacity of the built environment to resist the risk of debris flows in the Wenchuan earthquake-affected areas. [ABSTRACT FROM AUTHOR]

Chronology of debris flow deposits (DFD) is crucially important in understanding fan evolution and assessing the risks of future extreme disaster events. To establish the debris flow history in a long-term temporal framework, multiple debris flow and flash flood events were examined from the Sandaoqiao (SDQ) gully near the large-scale active Xianshuihe faults, eastern Tibetan Plateau. The rough and discontinuous structures indicate DFD are characterized by "linear stone structure" and boulders enclosed by clayey silts in the SDQ gully. On the basis of debris flow sedimentary characteristics, we develop a valid sampling strategy involving 14C and OSL dating methods (13 radiocarbon and 3 OSL ages) on the debris flow fan. The major stages of debris flow aggradation were identified at ~ 35 kyr B.P., 23‒22 kyr B.P., ~ 13 kyr B.P. and 3.9‒1.4 kyr B.P. since the Last Glacial (last ~ 35 kyr B.P.). And gully-fill deposits were more abundant during the latest Pleistocene (35‒13 ka) than current phase. Late Holocene debris flow and flash flood events recur in the mid-channel from 3.9‒3.8 to 1.9‒1.4 kyr B.P., which was probably triggered by palaeo-earthquake events associated with active faults. The current phase is dominated by debris flood events and the maximum discharge is estimated as ~ 290 m3/s. This study provides key chronology for understanding multiple debris flow stages associated with regional tectonic activity and climatic change in the eastern Tibetan Plateau. [ABSTRACT FROM AUTHOR]

In the field of rock engineering, complexity of stress environment is an important factor affecting its stability. Thus, in view of fracture mechanism of rock under different loading rates within the scope of quasi-static strain rate, four groups of uniaxial compression tests with different strain rates were carried out on sandstone specimens, and strength, deformation, failure modes and acoustic emission characteristics of specimens were compared and analyzed. Furthermore, the fracture mechanism was discussed from the perspective of fracture characteristics based on fractal dimension, crack propagation law inverted through acoustic emission b-value, and micro fracture morphology. The results showed that as the strain rate increased from 10 to 5 s-1 to 10-2 s-1, the fractal dimension of rock fragments increased, and the fractal dimension of rock fragments increased by 9.66%, 7.32%, and 3.77% successively for every 10 times increase in strain rate, which means that the equivalent size of fragments was getting smaller, and the fragmentation feature was becoming increasingly prominent. The crack propagation process based on acoustic emission b-value showed that with the increase of loading rate, the specimen entered the rapid crack propagation stage earlier, in order of 68%, 66%, 29%, and 22% of peak stress. Moreover, the microscopic fracture morphology showed that with the increase of loading rate, transgranular phenomenon was clear, and the fracture morphology changed from smooth to rough. That meant that the fracture of sandstone rock at high loading rates was mainly caused by the propagation of large cracks, which was different from the slow process of initiation, convergence and re-propagation of small cracks at low strain rates. Due to warm and humid air currents of the Indian Ocean and the southwest monsoon, the Palong Zangbo catchment in southeastern Tibet has developed oceanic glaciers in the valley, and the activity of glacial debris flows has been gradually intensified under neotectonic activity, frequent earthquakes, climate change, and extreme rainfall. In this paper, the topographic and morphological data of the debris flow basin, the dynamic evolution characteristics of glaciers and glacial lakes were analyzed by using multisource long-term series of remote sensing images. Simultaneously, the distribution of moraines and landslide sources were extracted based on satellite image. In addition, climate change in the study area was analysed using temperature and rainfall data from the last 40 years, revealing that the average temperature in the study area from May to October presented a fluctuating tendency as a whole, especially after 2013, when the temperature gradually increased. As these temperature changes led to continuous melting of the glaciers in the study area, the glacier area decreased from 8,300 km2 in 1988-4,584 km2 in 2019, which decreased nearly 45%. However, the number and area of glacial lakes in the study area gradually increased under a power-law trend, which further led to a significant increase on the possibility of glacial lake rupture in the study area. Due to the joint effects of earthquakes, glacier melting and glacial lake collapse, the debris flows in the study area were well developed, and a total of 122 debris flows were found with varying channel lengths, areas and material sources. Importantly, the characteristics of the glaciers, glacial lakes and climate change in the study area have indicated that the glaciers have retreated, the number of glacial lakes has increased, and the risk of debris flow in this basin will increase in the future. Therefore, it is necessary to strengthen monitoring and early warnings on floods due to glacial lake collapses and debris flows in the study area to improve the risk management of debris flows and floods and the prevention and mitigation of disasters. [ABSTRACT FROM AUTHOR]

Until the Mw 6.6 Luding earthquake ruptured the Moxi section of the Xianshuihe fault (XSHF) on 5 September 2022, the region had not experienced an Mw >6 earthquake since instrumental records began. We used Global Positioning System (GPS) and Sentinel-1 interferometric synthetic aperture radar (InSAR) observations to image the coseismic deformation and constrain the location and geometry of the seismogenic fault using a Bayesian method We then present a distributed slip model of the 2022 Mw6.6 Luding earthquake, a left-lateral strike-slip earthquake that occurred on the Moxi section of the Xianshuihe fault in the southwest Sichuan basin, China. Two tracks (T26 and T135) of the InSAR data captured a part of the coseismic surface deformation with the line-of-sight displacements range from ∼−0.16 m to ~0.14 m in the ascending track and from ~−0.12 m to ~0.10 m in the descending track. The inverted best-fitting fault model shows a pure sinistral strike-slip motion on a west-dipping fault plane with a strike of 164.3°. We adopt a variational Bayesian approach and account for the uncertainties in the fault geometry to retrieve the distributed slip model. The inverted result shows that the maximum slip of ~1.82 m occurred at a depth of 5.3 km, with the major slip concentrated within depths ranging from 0.9–11 km. The InSAR-determined moment is 1.3 × 1019 Nm, with a shear modulus of 30 GPa, equivalent to Mw 6.7. The published coseismic slip models of the 2022 Luding earthquake show apparent differences despite the use of similar geodetic or seismic observations. These variations underscore the uncertainty associated with routinely performed source inversions and their interpretations for the underlying fault model. [ABSTRACT FROM AUTHOR]

Rma (also called Qiang) is a Sino-Tibetan language spoken in Northwestern Sichuan, China. In the literature on Rma, all documented varieties of Rma have been reported to have a three-way voice onset timing (VOT) distinction between voiceless unaspirated, voiceless aspirated, and voiced unaspirated obstruents. This study reports a variety of Rma, which has a near merger of the voiceless unaspirated and voiced unaspirated stops. A pilot study was conducted with speakers from three different villages within Yonghe valley. The results of this empirical study suggest that the Lower Yonghe valley variety has innovated a near merger between voiced and voiceless unaspirated obstruents. [ABSTRACT FROM AUTHOR]

On January 8, 2022, an M6.9 earthquake occurred in Menyuan, Qinghai, which caused surface damage. In this paper, the line-of-sight (LOS) coseismic surface deformation field is obtained by the interferometric synthetic aperture radar (InSAR) of the Sentinel-1 satellite. Constrained by the InSAR surface deformation field, a Bayesian method based on sequential Monte Carlo sampling was used to invert the geometric parameters of seismogenic faults and the distribution of fault slip. Moment magnitude of the model is Mw6.6. The earthquake was determined to occur at a left-lateral strike-slip fault. Based on the historical strong earthquake dislocation model, the PSGRN/PSCMP program was used to calculate the Coulomb stress change at the epicenter of the 2022 Menyuan M6.9 earthquake caused by the surrounding historical strong earthquakes. The results show that the occurrence of the Gulang M8 earthquake in 1927, the Menyuan Mw5.7 in 1986 and the Menyuan Mw5.9 earthquake in 2016 caused a significant increase in Coulomb stress at the epicenter of the 2022 Menyuan earthquake. The coseismic and post-seismic Coulomb stress increases were greater than 0.01 MPa. Combined analysis of this result with regional tectonic stress, allows us to conclude that the 2022 Menyuan M6.9 earthquake occurred on the dynamic background of the continuous extrusion of the Indian plate towards the Eurasian plate, and the regional historical strong earthquake activity played a significant role in promoting it. The research results provide a theoretical basis for understanding the seismogenic background and dynamic mechanism of the 2022 Menyuan earthquake. [ABSTRACT FROM AUTHOR]

Introduction: Previous studies on associations between social support and quality of life (QoL) have usually employed a variable‐centered approach, without considering individual variances in time‐varying changes in social support. This study explores trajectories of social support and whether depressive symptoms mediate associations between social support trajectories and QoL 10 years after an earthquake. Methods: Seven hundred and forty‐four Chinese adolescents exposed to the Wenchuan earthquake were surveyed on social support at 6‐, 18‐, and 24‐months and depressive symptoms at 30‐months postearthquake (T30m). They provided valid data on QoL after 10 years of the earthquake (T10y). The latent class growth analysis was used to estimate social support trajectories. Mediation analysis was then conducted to test whether depressive symptoms at T30m mediated associations between social support trajectories and QoL at T10y. Results: Three trajectories of social support were identified: low decreasing (31.6%), moderate decreasing (55.4%), and persistent high (13.0%) groups. Depressive symptoms significantly mediated the effects of social support trajectories (relative to the low support trajectory) on future QoL (95% CIs: 0.70–1.78 and 1.41–3.37 for moderate decreasing and persistent high groups, respectively). Conclusions: Social support shows individual differences over time. Moderate and high social support trajectories improve 10‐year QoL partly by reducing depressive symptoms. Therefore, interventions aimed at enhancing social support and reducing depressive symptoms may be more effective in enhancing QoL in the aftermath of disasters. [ABSTRACT FROM AUTHOR]

This paper investigates the reconstruction of Albanian identity in Kosovo after the region's transformation to state independence in 2008. The cultural environment emerged as a site of ethnic appropriation and contestation in the longstanding interethnic struggles between the Albanians and the Serbs. The study examines the socio-symbolic and linguistic manifestations of national identity in Pristina, the capital city of Kosovo, through the lens of Linguistic Landscape Studies. The first aspect of the study investigates M. Theresa Boulevard, the central promenade of the city and a site of memory and commemoration, to highlight how the period of South Slavic hegemony in Kosovo and the recent interethnic war resulted in a redefinition of Albanian identity. The second aspect of the study focuses on the written manifestation of the Gheg variety of Albanian as a symbol of Kosovo's independence. Through this dual focus on memory and language, the study aims to arrive at an understanding of how new national and political self-identifications are shaped in contexts that have undergone ethno-political conflicts and socio-political shifts. We argue that the symbolic configuration of Kosovo suggests a redefinition of Kosovo-based Albanian identity following the transformation to state independence. The study contributes to an understanding of the multi-layered redefinition of Albanian identity in Kosovo, calling attention to language and memory in the process of constructing national identities in postwar contexts. [ABSTRACT FROM AUTHOR]

Intense rainfall events in mountain regions result in pronounced geomorphic activity including landslides, debris flows, sediment transport, and large woody debris. This study investigated the factors that affect wood deposition patterns during debris flows and the influence of wood on sediment deposition. We conducted flume experiments to simulate debris flow fans with driftwood and divided the experiments into plain and confluence sets. The plain set considered the condition where the debris flow tributary met a mild terrain, whereas the confluence set considered where the tributary met a mainstream. The results revealed that wood with roots was liable to form a log jam on the tributary, and small logs could travel long distances. In the confluence set, the mainstream flow caused asymmetric expansion of the debris flow fan and drove the small wood logs drifting downstream. In addition, wood logs may affect the sediment morphology, particularly in the plain set, which has no mainstream effect. In the plain set, driftwood constricted the development of fans in both volume and area. The wood also deflected the path and deposition of debris flows, causing an uneven fan surface. Our experiment results were consistent with the Japanese historical events, including the asymmetrical fans expansion in the confluence environment and the correlation between the travel distance and the size of the driftwood. This study provides valuable insights into the deposition patterns of debris flows with driftwood in mountain regions, filling the gap left by previous researches in driftwood-influenced debris flow deposition on fans. [ABSTRACT FROM AUTHOR]

The central-southern part of the eastern border of the Sichuan-Yunnan rhombic block provides the research strategy of 'trade space for time' with an interesting fault system, where the segments have similar focal mechanisms and cover almost continuous spectra of elapse rates. We experiment to study the seismological characteristics of different segments with different elapse rates. We employed the de-clustered earthquake catalog for the calculation of b values for each segment. The analysis revealed that different segments have similar b values, which implies that, although different segments have different periods of earthquake recurrence, the 'natural time' for the whole fault system elapses with a homogeneous pace. We extended the earthquake potential score (EPS) for nowcasting earthquakes to a quasi-EPS (qEPS). It is found that qEPS increases with the increase of elapse rates, albeit for those fault segments whose elapse rates have exceeded 1, qEPS may better reflect the seismic hazard. [ABSTRACT FROM AUTHOR]

Mountain disasters, such as landslides and debris flows, are becoming more prevalent due to abnormal weather patterns. Debris flows, triggered by heavy rainfall, are causing escalating damage to residential areas and roads as they surge down mountain streams. In order to both mitigate this damage and comprehend the underlying causes of such mountain disasters, comprehensive field investigations were carried out in regions where debris flows had transpired. To establish spatial information for analyzing vulnerable areas, GIS data were employed. Additionally, precise measurements of the actual extent of debris flow in targeted zones were obtained through the utilization of terrestrial LiDAR scanning. Subsequently, the process of debris flow was replicated using FLO-2D, a numerical model designed for such scenarios. This simulation incorporated actual rainfall data that had precipitated debris flow incidents, as well as probability-based rainfall data corresponding to return periods of 30, 50, and 100 years. Key parameters, including flow depth, velocity, and diffusion area, were compared across different scenarios. The sedimentation area of the section where debris flow originated, as determined from terrestrial LiDAR scan data, was estimated to be approximately 21,300 square meters. The outcomes of the FLO-2D simulation revealed that the diffusion area for Case I was approximately 20,900 m2, while the simulated diffusion area for a 100-year return period was calculated to be 40,725 m2. Furthermore, flow depth, velocity and diffusion area exhibited a gradual incremental trend in simulation results. [ABSTRACT FROM AUTHOR]

Buildings' energy resilience in natural disasters is reliant on the support of the functionalities of critical infrastructure that the buildings connect to, such as highway-bridge and electric power systems. Meanwhile, as critical infrastructure systems have increasingly become interconnected and interdependent, they are more susceptible to natural hazards and less able to withstand their effects. Insufficient research has been conducted regarding computational models of effectively representing the interdependencies and interactions involved in the restoration scheduling of post-disaster critical infrastructure systems. To address this research gap, this study proposes integer programs, integrating hybrid genetic algorithms, to explicitly investigate the impact of interactions and interdependencies between electric power systems (EPSs) and highway-bridge systems (HBSs) on the energy-recovery processes of buildings. The objective is to dynamically prioritize the restoration scheduling for EPSs and HBSs while considering inspection and restoration activities. A case study based on the 2008 Wenchuan Earthquake in Sichuan province, China, is employed to validate the efficacy of the proposed method. The results of the analysis reveal that the dynamic model exhibits a substantial 6.4% improvement in building energy resilience at the seven-day mark, compared to the static model. Moreover, the proposed coupled EPS–HBS inspection–restoration joint model outperforms a disjoint EPS inspection–restoration scheduling model, yielding a remarkable 11.4% enhancement in system resilience at the seven-day mark. These findings underscore the significance of considering interdependencies and interactions within critical infrastructure systems to enhance the energy resilience of buildings in earthquake-affected areas. [ABSTRACT FROM AUTHOR]

In this study, we propose quantifying the Amu River riverbank erosion with the modelled river discharge in Kaldar District, Balkh Province of Afghanistan from 2004 to 2020. We propose a framework synergizing multi-source information for modelling the erosion area based on three components: (1) river discharge, (2) river width, and (3) erosion area. The total river discharge for the watershed shared by Afghanistan and Tajikistan was modelled using hydrological parameters from the European Centre for Medium-Range Weather Forecasts (ECMWF) Reanalysis v5 (ERA5) data through multivariate linear regression with ground station data. The river width was determined manually using the Normalized Difference Water Index (NDWI) derived from Landsat data. The riverbank erosion area was derived from the digital shoreline analysis using the NDWI. The digital shoreline analysis showed that, between 2008 and 2020, the average riverbank erosion area in Kaldar District is about 5.4 km2 per year, and, overall, 86.3 km2 during 2004–2020 due to flood events. The significantly higher land loss events occurred at 10 km2 bank erosion during the years 2008–2009 and 2015–2016, and 19 km2 peak erosion occurred during 2011–2012. A linear relation between the erosion area with respect to the discharge intensity and the specific stream power was observed with an R2 of 0.84 and RMSE of 1.761 for both. [ABSTRACT FROM AUTHOR]

Communities downstream from burned steeplands face increases in debris-flow hazards due to fire effects on soil and vegetation. Rapid postfire hazard assessments have traditionally focused on quantifying spatial variations in debris-flow likelihood and volume in response to design rainstorms. However, a methodology that provides estimates of debris-flow inundation downstream from burned areas based on forecast rainfall would provide decision-makers with information that directly addresses the potential for downstream impacts. We introduce a framework that integrates a 24-hour lead-time ensemble precipitation forecast with debris-flow likelihood, volume, and runout models to produce probabilistic maps of debris-flow inundation. We applied this framework to simulate debris-flow inundation associated with the 9 January 2018 debris-flow event in Montecito, California, USA. Sensitivity analyses indicate that reducing uncertainty in postfire debris-flow volume prediction will have the largest impact on reducing inundation outcome uncertainty. The study results are an initial step toward an operational hazard assessment product that includes debris-flow inundation. [ABSTRACT FROM AUTHOR]

This paper explores the genesis and growth of the current Chinese wireless network infrastructures by pulling together the historical threads of two telecommunications infrastructures: first, the development of the first-tier inter-provincial optical backbone, the "Eight Vertical and Eight Horizontal Fibre-optic Grid," in the late 1980s and 1990s; and second, the deployment of two broadband-access cellular networks, the third-generation (3G) cellular networks in 2008 and the fourth-generation (4G) networks from 2013 to now, which constitute the wireless network's edges. I insert the development of Chinese wireless networks since the 1980s into the interconnected global technological environment, contextualizing the infrastructure deployment in the history of Sino-American technological cooperation and competition, traversing the final decade of the Cold War era (the 1980s), the dual global expansion of economic neoliberalism and informational technology since the 1990s and the crisis of global capitalism since 2008. This historical inquiry reconciles two historical (meta-)narratives that are not always compatible with each other – the Chinese narratives grounded on the overarching concept of Chinese post-socialism, and the narratives in Western discourses that often evoke Cold War/post-Cold War dialectics. This paper examines the global distribution of wireless network infrastructures on the basis of commercialization, technology transfers and trades of techno-commodities across borders, challenging the reduced depiction of the Chinese wireless network as an extension, or an exception, to the West-centred techno-capitalist system. [ABSTRACT FROM AUTHOR]

The aim of the article is to present the security determinants as well as changes regarding the strategic priorities of state security of Georgia after the war with Russia in 2008. Since the beginning of the system transformation into a legal democratic state, Georgia has been developing essential reforms that involved the establishment of democratic institutions, state modernisation, the development of a free trade economy, as well as directed towards Euro-Atlantic and western institutions for co-operation and security. In the international dimension, these efforts have met the encouragement and support of the western and democratic states and institutions, especially NATO and the EU. On the other hand, Georgia had to face the huge opposition from the Russian Federation that aimed to maintainits previous area of influence and oppose the pro-western development in the region of South Caucasus. The war in 2008 (Russian aggression) slowed down these transformation processes and was the reason for the change of perceiving the security environment of Georgia and the role and attitude of Russian Federation towards the post-Soviet space. It resulted in necessary efforts to rebuild the country after the ravages of war on the one hand, and in the considerable change regarding the restoration of institutions and possibilities connected with the main security goals on the Georgian pro-democratic and pro-western way. [ABSTRACT FROM AUTHOR]

Post-traumatic stress (PTSD) disorder is a mental health condition that can occur after experiencing or witnessing a traumatic event. The 27-F earthquake that struck Chile in 2010 was one such event that had a significant impact on the mental health of the population. A study was conducted to investigate the prevalence of PTSD and its associated factors among survivors of this earthquake. The study was a longitudinal design, involving a sample of 913 patients aged 18 to 75 years who attended 10 Primary Care Centers in Concepción, Chile. The Composite International Diagnostic Interview (CIDI) was used to assess both depressive episodes (DE) and PTSD before and after the earthquake. The study also involved genotyping studies using saliva samples from the participants, specifically focusing on the Val66Met and 5-HTTLPR polymorphisms. Statistical analysis was performed to examine the association between different variables and the presence of PTSD. These variables included demographic factors, family history of psychiatric disorders, DE, childhood maltreatment experiences, and critical traumatic events related to the earthquake. The results showed that the incidence of post-earthquake PTSD was 11.06%. No significant differences were found between the groups of participants who developed post-earthquake PTSD regarding the Val66Met or 5-HTTLPR polymorphisms. However, a significant association was found between the concomitant diagnosis of DE and the development of post-earthquake PTSD. The presence of DE doubled the risk of developing post-earthquake PTSD. The number of traumatic events experienced also had a statistically significant association with an increased risk of developing post-earthquake PTSD. The study's limitations include the potential interference of different DE subtypes, the complexity of quantifying the degree of earthquake exposure experienced by each individual, and events entailing social disruption, such as looting, that can profoundly influence distress. In conclusion, the study found that PTSD following the 27-F earthquake in Chile was associated with a concomitant diagnosis of DE and the number of traumatic events experienced. The study did not find a significant association between PTSD and the Val66Met or 5-HTTLPR polymorphisms. The researchers recommend that mental health professionals should prioritize the detection and treatment of concomitant depressive episodes and exposure to critical traumatic events in survivors of disasters. They also suggest that further research is needed to better understand the relationship between genetic factors and post-disaster PTSD. [ABSTRACT FROM AUTHOR]

The goal of this study was to accurately evaluate the lateral sealing ability of a fault in siliciclastic stratum based on previous analysis of the lateral sealing of faults by a large number of scholars in the published literature and physical simulation experiments. Content of the clay mineral phase and the diagenetic degree of fault rock were investigated as the main factors to evaluate the lateral sealing of faults. Based on this theory, the configuration relationship between the clay content and burial depth of fault rock (SGR&H) threshold evaluation method for the lateral sealing of faults was established. Then, we applied these results to evaluate the lateral sealing ability of faults in the Beixi, Beier, Wuerxun, and Surennuoer areas in the Hailar Basin, China. The variation in SGR boundary values with burial depth between the lateral opening and moderate sealing area, as well as between the moderate and strong sealing area of the faults, are obtained. Compared with the previous methods, the SGR&H threshold method transforms the static SGR value of a formation or even a region into a dynamic SGR value that changes with the burial depth, which can fully characterize the differences in the conditions required for sealing faults with different internal structures at different depths. In determining the lateral sealing ability of faults by comparing the evaluation results, we discovered the following. (1) In the same area, the sealing thresholds of faults within different layers are different because the deep strata are subjected to greater pressures and longer loading times, so these faults are more likely to seal laterally. (2) In the same layer, the sealing thresholds of faults in different areas are also different. The higher the thickness ratio between the sandstone and the formation (RSF), the smaller the entry pressure of the fault rock when it has reached a critical seal state, so the SGR&H thresholds are relatively small. Compared to the previous methods, the SGR&H threshold method in this article reduces the exploration risk of faults with relatively low diagenetic degree in shallow strata, and also increases the exploration potential of faults with relatively high diagenetic degree in deep strata. The evaluation results are more consistent with the actual underground situation. [ABSTRACT FROM AUTHOR]

The structural change of the Svalbard landscape from glacially dominated to paraglacial, that has taken place since the termination of the Little Ice Age (ca. 1900) is expressed by the widespread retreat of glaciers and progressive exposure of glacial landforms. This study provides insights into the rate of post‐LIA deglaciation and associated paraglacial transformation in the foreland of Gåsbreen, one of the first ever investigated glacier systems in the Arctic. Glacier is situated in Sørkapp Land (Southern Spitsbergen), a region characterized by one of the fastest deglaciation rates in the entire Svalbard Archipelago. During the investigated period, 1938–2020, the Gåsbreen was in a recession that accelerated after 1990, leading to its foreland increasing from 2.2 to 5.8 km2. The dynamics of landscape change in the glacier foreland, exposed since the end of LIA, manifested in i.e. the formation of ice‐dammed lakes, degradation in the surface of ice‐cored moraines and the landforms that are underlain by dead‐ice. Mass movements and debris flow on ice‐cored moraines and fluvioglacial processes had a great influence on this transformation. Enhanced proglacial runoff intensified denudation, transport and accumulation of sediments, which resulted, in: an increase in the extent of sandurs and proglacial riverbeds, an increase in the area of glacial lakes, extending and changing of the course of rivers in the glacier foreland. At the same time, the major lake system in the area—Goësvatnet underwent several cycles of filling and draining, often through glacial outburst flooding events. [ABSTRACT FROM AUTHOR]

On September 5, 2022 (local time), a magnitude 6.6 earthquake was reported to have occurred in Luding County, Sichuan Province, Southwest China. In this simulation, a widely used stochastic finite-fault model was used to analyze how the source models affect the near-fault earthquake ground motion simulations of the 2022 Mw 6.6 Luding earthquake in China. Seven different slip models, one of them obtained from common fault parameters and random distributed slip amount, were used to yield the best match with the recordings. The simulated earthquake ground motions calculated in the frequency band of 0.05–20 Hz were compared with the observed values in both the time and frequency domains. Twelve acceleration observation stations located near the fault plane were selected in our simulation for comparison. The average H/V curves were estimated using the available acceleration records to consider the local site effect at each selected station. The research results indicate that none of the source models adopted in this study fully estimate the observed values at all the selected ground-motion stations. The simulated values of some slip models underestimate the level of the Fourier amplitude spectrum at frequencies above 6 Hz. The underestimation may be attributed to the directivity effect, which may produce a higher amplitude of observed ground motion in the high-frequency band. All the slip models show similar average model deviations except for the random slip model. Finally, the peak ground accelerations and peak ground velocities were predicted at these selected near-fault observation stations. The results indicate that the peak accelerations and velocities obtained from seven slip models correlate well with each other, but are slightly lower than the recorded values at most stations. In addition, the synthetized results calculated from the random and inverted slip models can be the same level only if a greater stress drop is adopted in the random model. [ABSTRACT FROM AUTHOR]

Background: Previous cross‐sectional studies have examined the relationship between self‐compassion and depression. Although it is often implicitly assumed that self‐compassion may increase the vulnerability of an individual to depression, only a few studies have assessed whether self‐compassion is a cause or a consequence of depression or both. Method: To examine such reciprocal effects, we assessed self‐compassion and depression via self‐report measures. At the baseline assessment (Time 1, T1), 450 students (M = 13.72, SD = 0.83, 54.2% females) participated 10 months after the Jiuzhaigou earthquake. We reassessed the T1 sample after 6‐ and 12‐month intervals. At Time 2 (T2) assessment, 398 (56.0% female participants) of the Wave 1 participants were retained, and at Time 3 (T3) assessment, 235 (52.5% female participants) of the T1 and T2 participants were retained. Results: Cross‐lagged analyses indicated that positive self‐compassion could significantly reduce subsequent depression. However, depression did not significantly predict later positive self‐compassion. Negative self‐compassion at T1 increased depression at T2, but negative self‐compassion at T2 did not significantly predict depression at T3. In addition, positive self‐compassion significantly reduced subsequent negative self‐compassion. Conclusions: Positive self‐compassion appears to protect adolescents against depression and maintain this protection over time, whereas negative self‐compassion may worsen depression in adolescents during the initial stages of traumatic events. Additionally, positive self‐compassion may decrease the level of negative self‐compassion. [ABSTRACT FROM AUTHOR]

α and β are the two key parameters of the rainfall intensity-duration (ID) threshold curve for debris flow; the antecedent effective precipitation (AEP) poses influence on the ID threshold curve through changing α and β. It is critical to explore the correlations of α ~ AEP and β ~ AEP in order to quantify the influence of antecedent precipitation on ID threshold. However, the quantitative relationship between the AEP and the two parameters is still undetermined. In this study, a hydrological process–based numerical model that can derive the ID threshold curve is adopted to address this issue. Jiangjia Gully (JJG) in Dongchuan District of Yunnan Province, China, was chosen as the study area. The analysis results show that a higher AEP can provide favorable hydrological conditions for runoff generation and solid material resource recharge in JJG, but it do not always mean that the ID threshold condition for triggering debris flow is decreased. As for JJG, only after AEP > 40 mm, the AEP and ID threshold condition for triggering debris flow will be completely negatively correlated; when 15 mm ≤ AEP ≤ 40 mm, the solid material supply is rapidly increased by the AEP, a stronger hydrodynamic condition is required to transform them into debris flow meaning that the ID threshold condition for triggering debris flow is enhanced in JJG, and this positive correlation between them persists until the two ID threshold curves intersect in the I-D coordinate system. AEP will significantly change the position of the threshold curve in the I-D coordinate system, and the change law of the position of the ID threshold curve can be described by the functions of α ~ AEP and β ~ AEP. Due to the two functions, the ID threshold curve can regularly move in the I-D coordinate system rather than a conventional threshold curve stay the same regardless of AEP variation; it is beneficial to improve the prediction capacity of the ID threshold. [ABSTRACT FROM AUTHOR]

The Karakoram highway (KKH) is renowned for its complex natural environment and geological conditions. The climate changes drastically and directly influences the frequency and magnitude of debris flows in this region, resulting in significant casualties and economic losses. However, the risk assessment of debris flows along the KKH in the context of climate change has been rarely explored. Therefore, in this study we used the debris flow data, historical meteorological data and future climate prediction data to assess the debris flow risk of the study region during the baseline period (2009–2018), 2025s (2021–2030), 2035s (2031–2040) and 2045s (2041–2050) under the Representative Concentration Pathway 8.5 scenario. The results show that the risk of debris flows increases with climate change, with the highest risk level in the 2025s. Among different parts of this highway, the upper reaches of the Ghez River and the second half of Tashkorgan-Khunjerab are the sections with the highest risk. These findings are helpful for debris flow prevention and can offer coping strategies for the existing line of the KKH. They also provide some reference for the renovation, improvement, operation, and maintenance of the KKH. [ABSTRACT FROM AUTHOR]