Development of Building Inventory Data in Ulaanbaatar, Mongolia for Seismic Loss Estimation

During the last two decades, the rapid urbanization movement has increased the concentration of population and buildings in Ulaanbaatar city (UB), Mongolia. There are several active faults around UB. The estimated maximum magnitude of 7 in the Emeelt fault has been expected to significantly impact the UB region because the fault is only 20 km from the city. To consider the disaster mitigation planning for such large earthquakes, assessments of ground shaking intensities and building damage for the scenarios are crucial. In this study, we develop the building inventory data in UB, including structural types, construction year, height, and construction cost in order to assess the buildings’ vulnerability (repair cost) due to a scenario earthquake. The construction costs are estimated based on the procedure of the Mongolian construction code from the coefficients of cost per floor area for each structural type, and coefficients for heating system, floor areas, and buildings’ locations. Finally, the scenario’s economic loss of the damaged buildings is evaluated using the developed building inventory, global vulnerability curves of GAR-13, and estimated spectral accelerations.

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Life on the Wellington Fault: Managing Geological Collections and Earthquake Risk

Biodiversity Information Science and Standards ◽

10.3897/biss.2.26230 ◽

2018 ◽

Vol 2 ◽

pp. e26230

Author(s):

Delia Strong ◽

Marianna Terezow

Keyword(s):

New Zealand ◽

Earth Science ◽

Active Faults ◽

Earthquake Hazard ◽

Return Time ◽

Disaster Mitigation ◽

Earthquake Risk ◽

Ground Shaking ◽

Reference Collection

GNS Science is home to New Zealand’s national rock, mineral and fossil collections. The National Petrology Reference Collection (NPRC) is a ‘nationally significant’ collection of rocks and minerals from on- and off-shore New Zealand, Antarctica and the rest of the world. The National Paleontological Collection (NPC) is another nationally significant collection; of fossil material from New Zealand, the South West Pacific region and Antarctica, with some overseas additions. Their status as nationally significant collections mean that GNS Science is contracted by the New Zealand Government to provide long-term collection management. Collectively, the NPC and NPRC constitute more than 200,000 samples, dating from the earliest days of New Zealand geology exploration in the late 1800s. The collections continue to grow by hundreds to thousands of samples per year, and are loaned nationally and internationally for scientific research. They are by far the largest collections of fossils, rocks and minerals housed in New Zealand, and are important earth science archives for the entire Zealandian Southern Ocean region. The collections are housed on-site at GNS Science in Lower Hutt, a few hundred meters from the surface trace of the Wellington Fault and within striking distance of other active faults that could generate major earthquakes. Best estimates suggest that the Wellington Region has an average return time of about 150 years for very strong or extreme ground shaking. Such proximity to this significant, active hazard means that steps must be taken to ensure the long-term security and integrity of the collections in the event of earthquake shaking, as well as other natural and non-natural disasters. To that end, the collection managers have written and implemented disaster mitigation, preparedness and recovery plans for the National Petrology Reference Collection and National Paleontological Collection. Here we define the earthquake hazard posed by the Wellington Fault, assess the risk to the collections, and present steps taken to manage that risk.

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Do active faults’ clay mineral compositions affect whether earthquake ruptures they host will displace the surface?

10.5194/egusphere-egu21-8627 ◽

2021 ◽

Author(s):

Selina S. Fenske ◽

Virginia G. Toy ◽

Bernhard Schuck ◽

Anja M. Schleicher ◽

Klaus Reicherter

Keyword(s):

Fault Zone ◽

Clay Mineral ◽

Active Faults ◽

Surface Displacement ◽

Surface Rupture ◽

Near Surface ◽

Ground Shaking ◽

Physical Measurements ◽

Surface Displacements ◽

Earthquake Ruptures

<p>The tectonophysical paradigm that earthquake ruptures should not start, or easily propagate into, the shallowest few kilometers of Earth&#8217;s crust makes it difficult to understand why damaging surface displacements have occurred during historic events. The paradigm is supported by decades of analyses demonstrating that near the surface, most major fault zones are composed of clay minerals &#8211; particularly extraordinarily weak smectites &#8211; which most laboratory physical measurements suggest should prevent surface rupture if present. Recent studies of New Zealand&#8217;s Alpine Fault Zone (AFZ) demonstrate smectites are absent from some near surface fault outcrops, which may explain why this fault was able to offset the surface locally in past events. The absence of smectites in places within the AFZ can be attributed to locally exceptionally high geothermal gradients related to circulation of meteoric (surface-derived) water into the fault zone, driven by significant topographic gradients. The record of surface rupture of the AFZ is heterogeneous, and no one has yet systematically examined the distribution of segments devoid of evidence for recent displacement. There are significant implications for seismic hazard, which comprises both surface displacements and ground shaking with intensity related to the area of fault plane that ruptures (which will be reduced if ruptures do not reach the surface). &#160;We will present results of new rigorous XRD clay mineral analyses of AFZ principal slip zone gouges that indicate where smectites are present, and consider if these display systematic relationships to surface displacement records. We also plan to apply the same methodology to the Carboneras Fault Zone in Spain, and the infrequent Holocene-active faults in Western Germany.</p>

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An Assessment of Earthquake Scaling Relationships for Crustal Earthquakes in Indonesia

Seismological Research Letters ◽

10.1785/0220200267 ◽

2021 ◽

Author(s):

Endra Gunawan

Keyword(s):

Seismic Hazard ◽

Active Faults ◽

Hazard Model ◽

Strike Slip ◽

Coseismic Deformation ◽

Maximum Magnitude ◽

Scaling Relationships ◽

Rupture Length ◽

Scaling Relationship ◽

Earthquake Scaling

Abstract To estimate the hazard posed by active faults, estimates of the maximum magnitude earthquake that could occur on the fault are needed. I compare previously published scaling relationships between earthquake magnitude and rupture length with data from recent earthquakes in Indonesia. I compile a total amount of 13 literatures on investigating coseismic deformation in Indonesia, which then divided into strike-slip and dip-slip earthquake cases. I demonstrate that a different scaling relationship generates different misfit compared to data. For a practical practice of making seismic hazard model in Indonesia, this research shows the suggested reference for a scaling relationship of strike-slip and dip-slip faulting regime. On a practical approach in constructing a logic tree for seismic hazard model, using different weighting between each published earthquake scaling relationship is recommended.

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Reclaiming On-Site Upgrading as a Viable Resilience Strategy-Viabilities and Scenarios through the Lens of Disaster-Prone Informal Settlements in Metro Manila

Sustainability ◽

10.3390/su122410600 ◽

2020 ◽

Vol 12 (24) ◽

pp. 10600

Author(s):

Juan Du ◽

Stefan Greiving

Keyword(s):

High Risk ◽

Informal Settlement ◽

National Level ◽

Informal Settlements ◽

Community Resilience ◽

The Philippines ◽

Disaster Mitigation ◽

City Development ◽

Rapid Urbanization ◽

Metro Manila

The Philippines is argued as the only Southeast Asian country where informal settlers’ communities have been self-organized and produced discernible impacts on the country’s urban policies. As one of the high risk countries, fifty percent of the country’s informal settlements are located in danger and disaster-prone areas. However, informal settlement upgrading has not reached its significance in disaster mitigation and community resilience building. At the national level, on-site upgrading is not established in disaster risk management or climate change adaptation strategies, which explains the lack of strategic approaches for local implementation. Metro Manila serves as a suitable backdrop in this sense to study informal settlement upgrading under the condition of high risk and rapid urbanization with a high civil society engagement. This study investigates the underlined reasons why upgrading strategically falls short in addressing disaster mitigation and community resilience building. Theoretically, it questions what on-site upgrading is about. Empirically, two hazard-prone informal settlement communities within Metro Manila are examined with their different risk profiles, community development needs and resilience priorities. The core issues of upgrading are, therefore, differentiated at the settlement level with communities’ innate socio-economic and eco-spatial features over time. Meanwhile, the paper heightens the necessity of tackling on-site upgrading at the settlement level and articulating settlements’ spatial correlations with the city development, so as to sustain upgrading outcomes. In addition, this study attempts at setting up a range of scenarios conditioned with COVID pandemic fallout. It endeavors to provide another facet of how to deal with adaptation and resilience. This includes the urgent strategy shift in the housing sector and its financial sustainability, innovative mechanisms to manage uncertainty and risks, lessons for post-COVID planning, etc.

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Integrating faults and past earthquakes into a probabilistic seismic hazard model for peninsular Italy

Natural Hazards and Earth System Science ◽

10.5194/nhess-17-2017-2017 ◽

2017 ◽

Vol 17 (11) ◽

pp. 2017-2039 ◽

Cited By ~ 13

Author(s):

Alessandro Valentini ◽

Francesco Visini ◽

Bruno Pace

Keyword(s):

Seismic Hazard ◽

Seismic Activity ◽

Grid Point ◽

Active Faults ◽

Gaussian Model ◽

Probabilistic Seismic Hazard ◽

Maximum Magnitude ◽

Slip Rates ◽

Earthquake Sources ◽

The Impact

Abstract. Italy is one of the most seismically active countries in Europe. Moderate to strong earthquakes, with magnitudes of up to ∼ 7, have been historically recorded for many active faults. Currently, probabilistic seismic hazard assessments in Italy are mainly based on area source models, in which seismicity is modelled using a number of seismotectonic zones and the occurrence of earthquakes is assumed uniform. However, in the past decade, efforts have increasingly been directed towards using fault sources in seismic hazard models to obtain more detailed and potentially more realistic patterns of ground motion. In our model, we used two categories of earthquake sources. The first involves active faults, and using geological slip rates to quantify the seismic activity rate. We produced an inventory of all fault sources with details of their geometric, kinematic, and energetic properties. The associated parameters were used to compute the total seismic moment rate of each fault. We evaluated the magnitude–frequency distribution (MFD) of each fault source using two models: a characteristic Gaussian model centred at the maximum magnitude and a truncated Gutenberg–Richter model. The second earthquake source category involves grid-point seismicity, with a fixed-radius smoothed approach and a historical catalogue were used to evaluate seismic activity. Under the assumption that deformation is concentrated along faults, we combined the MFD derived from the geometry and slip rates of active faults with the MFD from the spatially smoothed earthquake sources and assumed that the smoothed seismic activity in the vicinity of an active fault gradually decreases by a fault-size-driven factor. Additionally, we computed horizontal peak ground acceleration (PGA) maps for return periods of 475 and 2475 years. Although the ranges and gross spatial distributions of the expected accelerations obtained here are comparable to those obtained through methods involving seismic catalogues and classical zonation models, the spatial pattern of the hazard maps obtained with our model is far more detailed. Our model is characterized by areas that are more hazardous and that correspond to mapped active faults, while previous models yield expected accelerations that are almost uniformly distributed across large regions. In addition, we conducted sensitivity tests to determine the impact on the hazard results of the earthquake rates derived from two MFD models for faults and to determine the relative contributions of faults versus distributed seismic activity. We believe that our model represents advancements in terms of the input data (quantity and quality) and methodology used in the field of fault-based regional seismic hazard modelling in Italy.

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Analysis of the Losses Due to Flood and Waterlogging Disasters in China during 2006 to 2017

Proceedings ◽

10.3390/ecws-3-05820 ◽

2018 ◽

Vol 7 (1) ◽

pp. 25

Author(s):

Weiwei Shao ◽

Yuanfei Li ◽

Dianyi Yan ◽

Jiahong Liu ◽

Zhiyong Yang ◽

...

Keyword(s):

Flood Disaster ◽

Disaster Mitigation ◽

High Concentration ◽

Rapid Urbanization ◽

Analysis And Evaluation ◽

Flood Disasters ◽

Disaster Losses ◽

Disaster Control ◽

The Impact ◽

The Relationship

China is in a period of rapid urbanization. Due to the high concentration of population and industries, the loss due to flood and waterlogging is becoming more and more serious. Therefore, it is of great significance to strengthen the analysis and evaluation of the losses due to flood and waterlogging disasters in China for the recent years. This study analyzed the losses caused by flood and waterlogging disasters in China from 2006 to 2017. The results showed that the most serious year affected by floods and waterlogging was 2010. However, the relationship between rainfall and flood disaster losses was not significant, which may be because the occurrence of flood disasters is caused by many factors. The spatial distribution showed that the eastern and southern parts of China suffered greater losses from the flood and waterlogging disasters because these areas are more vulnerable to floods and waterlogging disasters under the impact of both monsoons and typhoons. This study hopes to provide some reference for flood disaster control and disaster mitigation in the future.

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Seismic damage to ancient monuments in Chiang Saen (Northern Thailand): implication for historical earthquakes in Golden Triangle area

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2018.0255 ◽

2019 ◽

Vol 377 (2155) ◽

pp. 20180255 ◽

Cited By ~ 1

Author(s):

Teraphan Ornthammarath

Keyword(s):

Eighteenth Century ◽

Large Scale ◽

Seismic Vulnerability ◽

Active Faults ◽

Lao Pdr ◽

Historical Earthquakes ◽

Geological Evidence ◽

Ground Shaking ◽

Golden Triangle ◽

Ancient Monuments

Over the last few decades, three moderate earthquakes (Mw greater than 6.0) occurred in and around the Golden Triangle area (including Myanmar, Thailand and Lao PDR) causing unprecedented damage and loss of lives in the epicentral region. In addition to the damage to modern structures, most heritage structures in Chiang Saen, a major city of the Lan Na kingdom (from the thirteenth to the eighteenth century), were also affected. This work is intended to present observed historical structure damage from recent earthquakes, which could provide evidence for the severity of historical earthquakes from the thirteenth to the eighteenth century. Based on historical records, geological evidence and observed damage to ancient monuments in this historic town, existing heritage stupas and temples constructed since the fourteenth century sustained only minor to moderate damage from these historical earthquakes. Considering the seismic vulnerability of these historical monuments, Chiang Saen might have never been subjected to severe ground shaking greater than MMI intensity VII, similar to the major earthquake in 460 A.D. along the Mae Chan fault, which was responsible for the large-scale liquefaction and inundation of ancient Yonok town. This information could be important for paleoseismological and historical earthquake research to constrain the recurrence interval of major active faults in this area. This article is part of the theme issue ‘Environmental loading of heritage structures’.

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(P1-86) Socioeconomic Impact of Natural Disasters in China

Prehospital and Disaster Medicine ◽

10.1017/s1049023x11004183 ◽

2011 ◽

Vol 26 (S1) ◽

pp. s126-s127

Author(s):

W. Zhang

Keyword(s):

Natural Disasters ◽

Natural Disaster ◽

Natural Hazards ◽

Natural Hazard ◽

Epidemiological Data ◽

Economic Loss ◽

Disaster Mitigation ◽

Socioeconomic Impact ◽

Chinese Government ◽

Chinese Yuan

IntroductionChina is one of the countries most affected by disasters caused by natural hazards. Disasters comprise an important restricting factor for economic and social development.MethodsRetrospective analysis was performed based on the epidemiological data of disasters caused by natural hazards in recent two decades.ResultsThe deadliest disaster that was reviewed was the Sichuan, Wenchuan earthquake on 12 May 2008 with a death toll of 88,928. Floods were the the primary natural hazard resulting in disaster in China. The economic loss caused by natural disasters was huge, the Sichuan earthquake alone resulted in an economic loss of 845.1 billion Chinese Yuan. However, psychosocial factors did not receive attention by Chinese Government and academics.ConclusionsThe characteristics and impact of disasters should be analyzed to scientifically provide useful information for natural disaster mitigation in China.

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