Sichuan Earthquake Research Articles

Analysing post-earthquake mass movement volume dynamics with multi-source DEMs

The 2008 Wenchuan earthquake in Sichuan, China, dramatically changed the terrain surface by inducing large numbers of landslides. Due to the lack of adequate pre- and post-earthquake Digital Elevation Models, the landslide volume estimation was done either using empirical area-volume relationships over large areas or by field surveys in a few catchments with debris flow threats. The trend of the change of volume of loose materials in the earthquake affected area over the decade since the earthquake remains largely unknown. In this study we were able to address this issue using nine DEMs taken at different years and from different sensors to study the change in loose material volume caused by co-seismic and post-seismic landslides over a period of 9 years. The area around the towns of Yingxiu and Longchi, for which also multi-temporal landslide inventories were available, was selected for this study. Methods to register the DEMs and minimize their vertically bias were applied. The quality of the DEMs was assessed through GCPs and terrain representation. As could be expected, high resolution DEMs showed more realistic volume estimates than the low resolution ones. The analysis showed that the frequency and magnitude of the landslide volume dynamics decreases significantly after the early post-seismic period, and in the last years human activities became a more dominate factor than mass movements. The post-seismic material loss from 2008 to 2014 was close to the gained volume of the co-seismic landslides, and the depletion of the materials was mostly at the toes of the co-seismic landslides. The analysis was done based on gain and loss calculated from the DEMs, and actual volumes could not be calculated due to unknown failure surface depths of the landslides.

Book review: Shaken Authority: China’s Communist Party and the 2008 Sichuan Earthquake

Book review: Shaken Authority: China’s Communist Party and the 2008 Sichuan Earthquake

Spatio-temporal evolution of mass wasting after the 2008 Mw 7.9 Wenchuan earthquake revealed by a detailed multi-temporal inventory

Strong earthquakes in mountainous areas can trigger a large number of landslides that generate deposits of loose and unconsolidated debris across the landscape. These deposits can be easily remobilised by rainfalls, with their movement frequently evolving into catastrophic debris flows and avalanches. This has been the fate of many of the 200,000 co-seismic deposits generated by the 2008 Mw 7.9 Wenchuan earthquake in Sichuan, China. Here we present one of the first studies on the post-seismic patterns of landsliding through a detailed multi-temporal inventory that covers a large portion of the epicentral area (462.5 km2). We quantify changes of size-frequency distribution, active volumes and type of movement. We analyse the possible factors controlling landslide activity and we discuss the significance of mapping uncertainties. We observe that the total number of active landslides decreased with time significantly (from 9189 in 2008 to 221 in 2015), and that post-seismic remobilisations soon after the earthquake (2008–2011) occurred stochastically with respect to the size of the co-seismic deposits. Subsequently (2013–2015), landslide rates remained higher in larger deposits than in smaller ones, particularly in proximity to the drainage network, with channelised flows becoming comparatively more frequent than hillslope slides. However, most of the co-seismic debris remained along the hillslopes and are largely stabilised, urging to rethink the way we believe that seismic activity affects the erosion patterns in mountain ranges.

Evolution and Distribution of the Early Aftershocks Following the 2008 Mw 7.9 Wenchuan Earthquake in Sichuan, China

AbstractUsing seismic data recorded by a dense temporary seismic array, we apply a waveform matched‐filter technique and obtain an early aftershock catalog around the mainshock rupture zone of the 2008 Wenchuan, Sichuan, China, earthquake. Specifically, we use 1,273 events in a relocated aftershock catalog as templates and scan through the waveforms within 7 days following the mainshock. We obtain up to ∼5.3 and ∼10 times more aftershocks than the standard and relocated catalogs, respectively. We find that early aftershocks mostly occurred below 10 km depth, downdip to large coseismic slip areas. Early aftershocks also show minor along‐strike migration with time since the mainshock, indicating triggering of afterslip following the mainshock. From the epicentral region to Beichuan where the mainshock slip was primarily reverse faulting, early aftershocks illustrated the Yingxiu‐Beichuan and Guanxian‐Jiangyou faults as high‐angle listric feature and rooted to a gentle dipping plane at the depth of ∼20 km. The aftershocks in the northeast segment of the Longmen Shan faults mostly occurred along a near‐vertical dipping fault, consistent with the primary strike‐slip component of mainshock slip in this region. In addition, differences in early and long‐term aftershock distribution indicate significant postseismic deformation along the conjugate Xiaoyudong fault. Our results help to illuminate the deep geometry of the Longmen Shan fault zone and the early evolution after the Wenchuan mainshock, which provides additional constraints to the mechanism of plateau uplifting.

Mobility, prosthesis use and health-related quality of life of bilateral lower limb amputees from the 2008 Sichuan earthquake.

The 2008 Sichuan Earthquake resulted in many amputees, yet due to the rare incidence, few studies have explored the rehabilitation outcomes and quality of life of bilateral lower limb amputees after major natural disasters. To evaluate rehabilitation outcomes of 17 young and adult bilateral lower limb amputees under the StandTall rehabilitation programme and to identify factors associated with successful functional recovery of bilateral amputees after large-scale disasters. Cross-sectional study. Mobility (amputee mobility predictor), prosthesis use (Houghton Scale) and health-related quality of life (Trinity Amputation and Prosthesis Experience Scale, Short Form 12) were evaluated through questionnaires and performance-based assessments. Means of scores were compared using T-tests. Subjects with bilateral through-knee or transtibial amputations had less activity restriction ( p < 0.01) and higher mobility ( p = 0.03). Subjects using prostheses more than 50% waking time had better general adjustment ( p = 0.02) and less functional restriction ( p = 0.01). Exercise and education were associated with higher mobility ( p = 0.06) and mental quality of life, respectively ( p = 0.09). Amputation level and knee joint salvage, prosthesis use, exercise and education were associated with better rehabilitation outcomes including ambulation, adjustment and quality of life in bilateral lower limb amputees from the 2008 Sichuan Earthquake. The study examined a unique group of traumatic bilateral lower limb amputees who were young and healthy before having traumatic amputations from a single episode of natural disaster. The factors associated with better functional recovery after the earthquake were investigated and may support future development of post-disaster rehabilitation strategies for bilateral lower limb amputees.

Deep Received Cosmologies, Enacted Extreme Environments, and Strategic Preoccupation with Failure

International experts recently posed insightful questions on fourteen topics that will guide the next generation of sensemaking theory, research, and practice: cognition, complexity, process, enactment, levels of analysis, loose coupling, emotions, requisite variety, theorizing, sensemaking, paradox, temporality, self-organizing, and morality (Tsoukas, Patriotta, Sutcliffe, & Maitlis, 2017). In order to inform past, current, and future studies of sensemaking episodes (e.g. the 12 May 2008 Sichuan Earthquake and the 2014 Shooting in Ferguson, Missouri), this study replicates an earlier qualitative meta-analysis of 80 industrial accidents that occurred around the world between 1903 and 1999 (e.g. 1912 Titanic naval accident, 1979 Three Mile Island nuclear accident, 1984 Bhopal chemical leak; see Lin, Zhao, Ismail, & Carley, 2006). The data set is updated from 80 industrial accidents to 120 sensemaking episodes through the addition of sensemaking episodes not included in the original data set (e.g. the 1977 Tenerife air disaster, Weick, 1990) and sensemaking episodes that occurred after the original data set was closed (e.g. the 2003 Columbia space shuttle disintegration, Beck & Plowman, 2009). The resulting qualitative meta-analysis helps respond to sensemaking research questions on cognition, complexity, and process through the elaboration of three components of anticipation resiilience processes in sensemaking episodes: deep received cosmologies, enacted extreme environments, and strategic preoccupation with failure.

Deep Received Cosmologies During Sensemaking: A Mixed Method Study of the 2008 Sichuan Earthquake

As scholars continue to seek ways to break through the thickening membrane that separates academics from executives, funding organizations such as The Templeton Foundation are championing alternati...

Co-Seismic Response of Bedrock Temperature to the Ms6.3 Kangding Earthquake on 22 November 2014 in Sichuan, China

In this paper, we report the co-seismic temperature response of the Ms6.3 Kangding earthquake in Sichuan, China, which occurred within a bedrock temperature monitoring station network constructed in the east of the Qinghai-Tibet Plateau. Results indicate that two kinds of co-seismic responses of bedrock temperature, exponential and step-rise ones, were recorded at different stations. As for the former, the amplitude of co-seismic response is about 5.6–11.5 mK (the average value is 7.33 mK), while the latter is about 0.31–0.98 mK (the average value is 0.52 mK). These two kinds of responses would be indicative of the two different mechanisms for change in temperature. On the one hand, the exponential responses represent the effects of fluid advection along the borehole wall, which are associated with a finite quantity of heat produced by earthquake-driven transient fluid flow. The step-rise responses, on the other hand, represent the direct response of temperature to change in the crustal stress accompanying with earthquake. We still tested relationship between stress variation and temperature response on the rock samples taken from the boreholes, and the average value is 0.77 mK/MPa. Upon thus, these step-rise temperature responses imply that co-seismic change in mean stress is about 0.40 MPa. We simplify effects of fluid by presuming a one-dimensional model where the flow is either up or down based on a pressure change due to compression or tension. The stress state, compression or tension, deduced by the direction of the fluid flow is qualitatively accordant with the direct response of bedrock temperature to stress change. In summary, characteristic changes in bedrock temperature occurred coincidentally with the earthquake at different stations, agreeing generally with regional stress adjustments accompanying the earthquake. Changes in bedrock temperature do seem to offer a useful means of monitoring dynamic changes in shallow crustal stress.

Research on Location-Allocation Problem of Emergency Logistics Based on Supply Chain Collaboration

The location of relief distribution centers and allocation of relief commodities are two of the most challenging issues in emergency logistics. This paper develops a multi-objective robust stochastic optimization model to determine the optimal location-allocation for emergency logistics problem considering the priority of demand points, the equity level between two demand points and the average removal time and cost for each relief commodity. In our model, not only demand, but also supplies and the state of roads in the post-disaster phase are considered as uncertain parameters. The proposed model simultaneously attempts to minimize the average of the weighted response times and the sum of the expected value and the variance of the total cost in the preparedness and response phase. Considering the global evaluation of two objectives, a compromise programming model is formulated and solved to obtain a non-dominating compromise solution. A case study of our robust stochastic optimization approach for disaster planning for the Great Sichuan Earthquake in China is presented to demonstrate that the proposed model can help in making decisions on both facility location and resource allocation in cases of disaster relief efforts.

Lidar Observations of Atmospheric Optical Characteristics during Sichuan Earthquake

The results of lidar observations of the atmosphere during the Sichuan (China) earthquake of 2008 are presented. It is shown that atmospheric parameters substantially changed during and after the earthquake. The profile of scattering characteristics formed in the lower troposphere differs from the original, which can serve as a predictor for earthquakes.

The Politics of Compassion: The Sichuan Earthquake and Civic Engagement in China. By Bin Xu. Stanford, Calif.: Stanford University Press, 2017. xiii, 256 pp. ISBN: 9781503602106 (cloth, also available in paper and as e-book).

The Politics of Compassion: The Sichuan Earthquake and Civic Engagement in China. By Bin Xu. Stanford, Calif.: Stanford University Press, 2017. xiii, 256 pp. ISBN: 9781503602106 (cloth, also available in paper and as e-book).

Bin Xu, The Politics of Compassion: The Sichuan Earthquake and Civic Engagement in China

Bin Xu, The Politics of Compassion: The Sichuan Earthquake and Civic Engagement in China

Did the 2008 Mw 7.9 Wenchuan Earthquake Trigger the Occurrence of the 2017 Mw 6.5 Jiuzhaigou Earthquake in Sichuan, China?

AbstractThe 2017 Mw 6.5 Jiuzhaigou earthquake occurred at the southeastern boundary of the Bayankala block in Tibetan Plateau. Here we investigate the spatial and temporal seismicity rate changes in the Jiuzhaigou region using the finite‐source epidemic‐type aftershock sequence model and stochastic declustering method. The background probabilities of all events are obtained, and the cumulative background seismicity is extracted and fitted by a linear function. Following from this, we argue that there was a decrease of background seismicity in Jiuzhaigou region immediately after the occurrence of the 2008 Mw 7.9 Wenchuan earthquake. On the other hand, we also calculate the static and viscoelastic stress changes in the area around the hypocenter of the Jiuzhaigou earthquake induced by the Wenchuan earthquake. Although opposite results are resolved by previous studies, we infer a negative Coulomb failure stress change under reasonable assumptions of parameters for this case. Combining these two observed empirical relationships, we conclude that the 2017 Jiuzhaigou earthquake is delayed by the Wenchuan earthquake and the former event possibly results from the southeastward movement of the Bayankala block, which in turn arises from the collision of Indian‐Australian Plate and the Eurasian Plate. These findings indicate that Bayankala block and its adjacent tectonic faults are still in the highly active seismic period that started in the 1990s.

Evaluation of Use of Prosthesis, Mobility, and Quality of Life in Young and Adult Persons with Unilateral Above-Knee Amputation 7 Years after the 2008 Sichuan Earthquake

ABSTRACT Background The 2008 Sichuan earthquake resulted in many casualties, also leaving a great number of persons with amputation who require long-term rehabilitation. Objectives This study aims to evaluate the use of prostheses, mobility, and quality of life and to determine factors associated with better rehabilitation outcomes 7 years after the earthquake for individuals from the StandTall rehabilitation program with traumatic unilateral above-knee amputation due to earthquake injuries. Method This is a cross-sectional study. Twenty-four individuals with unilateral above-knee amputation were recruited either at home visits or during clinic sessions between December 2014 and May 2015. Main outcome measures were 12-Item Short Form Survey Version 2, Amputee Mobility Predictor, Houghton Scale, and Trinity Amputation and Prosthesis Experience Scales. Results Adults with unilateral above-knee amputation experienced worse psychological adjustment to limitation (p = 0.018), more social activity restrictions (p = 0.072), and suffered from more residual limb pain (p = 0.024), and phantom pain (p = 0.044). Rehabilitation success was associated with less athletic restriction (p = 0.053), less functional restriction (p = 0.077), and greater prosthetic satisfaction (p = 0.085). Conclusions Adults with unilateral above-knee amputation experienced greater difficulties in psychological adjustment to limitation and social activities, even 7 years after the amputation. Residual limb and phantom pain were greatly affected by age. Prosthetic daily wearing time correlated with better functional outcome for individuals with unilateral transfemoral amputation. This study provides information regarding long-term rehabilitation outcomes of individuals with traumatic unilateral above-knee amputation. Age, daily prosthetic wearing time, and residual limb pain and phantom pain are main factors affecting rehabilitation outcomes of individuals with amputation. Physical quality of life and psychosocial quality of life are both impaired by amputation.

Contagion Effect of Natural Disaster and Financial Crisis Events on International Stock Markets

In the contemporary world bustling with global trade, a natural disaster or financial crisis in one country (or region) can cause substantial economic losses and turbulence in the local financial markets, which may then affect the economic activities and financial assets of other countries (or regions). This study focuses on the major natural disasters that occurred worldwide during the last decade, especially those in the Asia–Pacific region, and the economic effects of global financial crises. The heteroscedasticity bias correlation coefficient method and exponential general autoregressive conditional heteroscedasticity model are employed to compare the contagion effect in the stock markets of the initiating country on other countries, determining whether economically devastating factors have contagion or spillover effects on other countries. The empirical results indicate that among all the natural disasters considered, the 2008 Sichuan Earthquake in China caused the most substantial contagion effect in the stock markets of neighboring Asian countries. Regarding financial crises, the financial tsunami triggered by the secondary mortgage fallout in the United States generated the strongest contagion effect on the stock markets of developing and emerging economies. When building a diversified global investment portfolio, investors should be aware of the risks of major natural disasters and financial incidents.

Christian P. Sorace, Shaken Authority: China’s Communist Party and the 2008 Sichuan Earthquake

Christian P. Sorace, Shaken Authority: China’s Communist Party and the 2008 Sichuan Earthquake

Personal Transformation Process of Mental Health Relief Workers in Sichuan Earthquake.

After Sichuan earthquake, a few dedicated teams of psychological volunteers have been committed to helping the survivors of the disaster for a long period. Their personal transformation experiences were absent in the literatures. The purpose of this qualitative research was to adopt a qualitative research to examine individuals' lived experiences of personal transformation after long-term disaster mental health services. The study interviewed 10 psychological counselors, 3 psychiatric nurses, 4 psychiatrist, and 6 social workers. We built an explorative model to understand disaster relief workers personal transformation after long-term periods in disaster settings. The model proposes that existential learning is a key mediator factor from negative transformation to positive transformation. Cultivating the existential learning though training, caring and support involves a number of processes that includes acceptance, being authentic, and being mindful of here and now, which can transform their suffering to growth.

Emotional flexibility: Development and application of a scale in adolescent earthquake survivors.

Coping flexibility is strongly associated with individuals' well-being when coping with trauma. However an instrument to measure emotional flexibility, a specific type of coping flexibility, is yet to be developed. The present study reported the development and validation of a Self-Administered Inventory on emotional flexibility. The study also explored the relationship between emotional flexibility and psychological well-being in adolescents who had experienced the 2008 Sichuan earthquake in China. A sample of 327 adolescents from Beijing was recruited for item development and preliminary validation. Another sample of 941 middle school students from areas affected by the Sichuan earthquake was recruited for further validation and examination of its relationship with psychological well-being. Exploratory factor analysis and confirmatory factor analysis were used to examine the construct validity of the scale. The criterion validity of the measure was assessed using Pearson's correlation coefficient. The Emotional Flexibility Scale comprises 10 items covering 3 dimensions, namely tuning of positive emotions, emotion communication, and tuning of negative emotions. Emotional flexibility was positively correlated with cognitive flexibility and psychological well-being. The Emotional Flexibility Scale provides a brief, reliable, and valid measure of emotion regulation ability of adolescents faced with disasters. (PsycINFO Database Record

Media exposure related to the 2008 Sichuan Earthquake predicted probable PTSD among Chinese adolescents in Kunming, China: A longitudinal study.

This study examined the prevalence and the psychosocial predictors of probable PTSD among Chinese adolescents in Kunming (approximately 444 miles from the epicenter), China, who were indirectly exposed to the Sichuan Earthquake in 2008. Using a longitudinal study design, primary and secondary school students (N = 3577) in Kunming completed questionnaires at baseline (June 2008) and 6 months afterward (December 2008) in classroom settings. Participants' exposure to earthquake-related imagery and content, perceptions and emotional reactions related to the earthquake, and posttraumatic stress symptoms were measured. Univariate and forward stepwise multivariable logistic regression models were fit to identify significant predictors of probable PTSD at the 6-month follow-up. Prevalences of probable PTSD (with a Children's Revised Impact of Event Scale score ≥30) among the participants at baseline and 6-month follow-up were 16.9% and 11.1% respectively. In the multivariable analysis, those who were frequently exposed to distressful imagery had experienced at least two types of negative life events, perceived that teachers were distressed due to the earthquake, believed that the earthquake resulted from damages to the ecosystem, and felt apprehensive and emotionally disturbed due to the earthquake reported a higher risk of probable PTSD at 6-month follow-up (all ps < .05). Exposure to distressful media images, emotional responses, and disaster-related perceptions at baseline were found to be predictive of probable PTSD several months after indirect exposure to the event. Parents, teachers, and the mass media should be aware of the negative impacts of disaster-related media exposure on adolescents' psychological health. (PsycINFO Database Record

Relocation of mainshock and aftershock sequence of the &amp;lt;italic&amp;gt;M&amp;lt;/italic&amp;gt;&amp;lt;sub&amp;gt;s&amp;lt;/sub&amp;gt;7.0 Sichuan Jiuzhaigou earthquake

An earthquake of M s7.0 struck Jiuzhaigou Country in Sichuan Province on 8 August 2017. It occurred at the northeastern boundary of the Bayan Har block. The Jiuzhaigou earthquake was one of the largest earthquakes in continental China since the 2013 M s7.0 Lushan earthquake, and it was widely felt across Sichuan and adjacent provinces. The earthquake left 25 dead and up to 500 injured. Because the Jiuzhaigou earthquake did not produce obvious surface ruptures, the causative fault of this event was much debated. The shape of the seismogenic fault, the focal depth of the mainshock and the characteristics of the aftershock sequence were also not very clear. The Sichuan earthquake administration deployed 6 temporary seismic stations around the source region within 4 d of the mainshock. In this study, we collected seismic waveform data and phase arrival data recorded by permanent and temporary stations. We present a systematic investigation about the location of the Jiuzhaigou earthquake sequence with high precision. These results provide new constraints for refining earthquake rupture process, constructing seismogenic models, and evaluating regional earthquake risks. The mainshock of the Jiuzhaigou M s7.0 earthquake was relocated using a 3D velocity model. The procedure takes station elevation, topography and the Earth’s ellipticity into consideration. The location of the mainshock was found to be 103.806°E, 33.201°N, and the focal depth to be 20.4 km. The depth of the initial rupture point of the mainshock was estimated to be below 14 km with S-P arrival time difference recorded at the nearest strong motion station. The locations of early aftershocks were corrected with latter aftershocks recorded using dense temporary seismic stations. A double difference algorithm was used to relocate 1-month aftershock sequence of the Jiuzhaigou earthquake. The locations of 3030 aftershocks were here determined. The average location error was found to be 0.16, 0.15, and 0.18 km in the E-W, N-S, and U-D directions, respectively. The relocation results showed that the aftershocks spread approximately 42 km, trending NWW. The aftershock zone was found to connect the Tazang fault to the north and to the Huya fault to the south. The mainshock is located at the center of the aftershock zone, with similar aftershock length at the both sides. There is a ~5 km sparse aftershock segment to the NW of the mainshock which is consistent with large coseismic slip area. This phenomenon can be explained due to the large amount of stress released during the mainshock rupture. The depth of the aftershock in the northwest end was relatively shallow, and the aftershock zone was about 6 km wide. The depth of aftershock in the southeast section was deeper and the area was narrower, about 4 km. The predominant distribution of the focal depth is 4–20 km. The dip angle of the seismogenic fault is steep, with an average value of about 84°, and changes obviously along the strike direction. The seismogenic fault inclined to the southwest in the shallow part and to the northeast in the deep part. The complex fault shape should be considered when constructing seismogenic model and inverting earthquake rupture process. The depth of the initial rupture point of the mainshock is deeper than the centroid depth and average depth of the aftershock sequence, indicating that the earthquake rupture spreads from deep space to shallow. We find that the aftershocks migrated in the along-strike direction with logarithmic time since the mainshock. The length of the aftershock area expanded from 25 to 42 km in 2 d. The rate of spread was approximately 1.3 km/log(s), consistent with aftershock expansion caused by propagating afterslip. There may be afterslip in the source area of the Jiuzhaigou earthquake.