Potential Earthquake Research Articles

Mitigation and Optimization of Induced Seismicity Using Physics‐Based Forecasting

AbstractFluid injection can induce seismicity by altering stresses on pre‐existing faults. Here, we investigate minimizing induced earthquake potential by optimizing injection operations in a physics‐based forecasting framework. We built a 3D finite element model of the poroelastic crust for the Raton Basin, Central US, and used it to estimate time dependent Coulomb stress changes due to 25 years of wastewater injection in the region. Our finite element model is complemented by a statistical analysis of the seismogenic index (SI), a proxy for critically stressed faults affected by variations in the pore pressure. Forecasts of seismicity rate from our hybrid physics‐based statistical model suggest that induced seismicity in the Raton Basin, from 2001 to 2022, is still driven by wastewater injection despite declining injection rates since 2011. Our model suggests that pore pressure diffusion is the dominant cause of Coulomb stress changes at seismogenic depth, with poroelastic stress changes contributing about 5% to the driving force. Linear programming optimization for the Raton Basin reveals that it is feasible to reduce earthquake potential for a given amount of injected fluid (safety objective) or maximize fluid injection for a prescribed earthquake potential (economic objective). The optimization tends to spread out high‐rate injectors and shift them to regions of lower SI. The framework has practical importance as a tool to manage injection rate per unit field area to reduce induced earthquake potential. Our optimization framework is both flexible and adaptable to mitigate induced earthquake potential in other regions and for other types of subsurface fluid injection.

Mitigation strategies and policies recommendation for the economic impact of the Sunda Strait Megathrust: Seismic risk probability assessment and cost loss estimates

This study investigates seismic risk and potential impacts of future earthquakes in the Sunda Strait region, known for its susceptibility to significant seismic events due to the subduction of the Indo-Australian Plate beneath the Eurasian Plate. The aim is to assess the likelihood of major earthquakes, estimate their impact, and propose strategies to mitigate associated risks. The research uses historical seismic data and probabilistic models to forecast earthquakes with magnitudes ranging from 6.0 to 8.2 Mw. The Gutenberg-Richter model helps project potential earthquake occurrences and their impacts. The findings suggest that the probability of a major earthquake could occur as early as 2026–2027, with a more significant event estimated to likely occur around 2031. Economic estimates for a 7.8–8.2 Mw earthquake suggest potential damage of up to USD 1.255 billion with significant loss of life. The study identifies key vulnerabilities, such as inadequate building foundations and ineffective disaster management infrastructure, which could worsen the impact of future seismic events. In conclusion, the research highlights the urgent need for comprehensive seismic risk mitigation strategies. Recommendations include reinforcing infrastructure to comply with seismic standards, implementing advanced early warning systems, and enhancing public education on earthquake preparedness. Additionally, government policies must address these issues by increasing funding for disaster management, enforcing building regulations, and incorporating traditional knowledge into construction practices. These measures are essential to reducing future earthquake impacts and improving community resilience.

Experimental study on seismically isolated systems using a novel roller-type bearing with energy dissipation capacity

The roller-type isolation bearing is highly effective in limiting the transmission of lateral seismic forces to the superstructure. This paper introduces a novel roller-type bearing with energy dissipation capacity (RB-EDC), which includes flat bearing seats, rollers, limit plates with energy dissipation capability, and limit rings. The RB-EDC is characterized by its excellent energy dissipation capacity, simple manufacturing process, low cost, vertical tensile bearing capacity and stable performance in extremely cold regions due to its specific configuration and materials. The design procedure for the RB-EDC is detailed herein. Subsequently, pseudo-dynamic comparison tests were conducted on both a seismic isolation system specimen and a RC column specimen under frequent and rare earthquake conditions to validate the damping performance of the RB-EDC. The seismic isolation system consists of the RB-EDC and an RC column identical to the RC column specimen. The results indicate that, compared to the RC column specimen, the column in the seismic isolation system specimen significantly reduces crack distribution ranges, rebar strain, concrete strain, and displacement at the column top under seismic actions. The RB-EDC exhibits significant energy dissipation capacity even during frequent earthquakes, demonstrating effective damping performance. However, the residual displacement of the RB-EDC increases with seismic intensity, which may impact the damping performance of the bearing in future potential earthquakes, indicating the need for further redesign to incorporate self-centering capacity.

Crustal stress near the Yakutat microplate collision from probabilistic earthquake focal mechanisms

Earthquake source characteristics provide a valuable constraint on crustal stress and regional plate tectonics. Earthquake source studies in Yukon and northern British Columbia have been limited by sparse seismic network coverage. In this work, we leverage recent seismic network improvements to estimate focal mechanisms for small and moderate-magnitude (M>2.0) earthquakes from P-wave first-motion polarity data. We invert these data within a probabilistic framework to rigorously quantify mechanism uncertainties. Subsequently, probabilistic earthquake focal mechanisms are used as input for inversions for the orientation of principal stress axes, and stress shape ratio, for spatial windows throughout the region. We implement a novel, data-driven approach to propagate focal mechanism uncertainty in stress inversion. Our results improve the spatial coverage of existing earthquake focal mechanisms and enable an orogenic-scale study of crustal stress near the Yakutat-North America collision. Overall, the region is characterized by a transpressive stress regime. Maximum horizontal compressive stress orientations exhibit a pattern orthogonal to the Yakutat collision syntaxis. Stress inversion results also reveal an abrupt change in orientation east-to-west, which we interpret as a change in stress regime across the Fairweather-Connector-Totschunda fault system that is likely related to coupling between the subducting Yakutat slab and North America. This work improves our understanding of potential earthquake hazards in southwestern Yukon and the surrounding region.

Identification of Potential Earthquake Source Zones in Areas of Recent Tectogenesis Based on Geological and Geomorphological Factors and Tools of Fuzzy Logic: The Greater Caucasus

Identification of Potential Earthquake Source Zones in Areas of Recent Tectogenesis Based on Geological and Geomorphological Factors and Tools of Fuzzy Logic: The Greater Caucasus

Large‐Scale Extensional Strain in Southern Tibet From Sentinel‐1 InSAR and GNSS Data

AbstractIn this study, we utilize C‐band Sentinel‐1 radar images from 2015 to 2022, combined with interseismic horizontal GNSS velocities, to construct large‐scale, high‐resolution, 3‐D velocity and strain rate maps over a vast region of southern Tibet. We show the distribution of prevailing dilatational strain accumulation along the seven major rift zones. Using 2‐D elastic dislocations invoking a two‐fault model in a Bayesian framework, we quantified the decadal extension rates across the seven rift zones, and we suggest a total extension rate of 18.4 ± 1.7 mm/yr, consistent with geological and geodetic estimates. The resulting strain rate maps, combined with the earthquake catalog, help us identify areas with high earthquake potential. Our study enhances our understanding of the present‐day tectonics and kinematics in southern Tibet and provides important constraints for seismic hazard assessment in this region.

Earthquake Risk in Bangladesh: Lesson Learned from Turkiye-Morocco Earthquake

Turkey, Morocco, and Bangladesh are all located in active seismic zones of the Earth’s surface. Recent studies have predicted catastrophic earthquakes in Bangladesh in the near future. Since disasters can act as catalysts for learning by exposing the shortcomings and vulnerabilities of communities or governments, it is believed that Bangladesh has much to learn from the 2023 mega-disasters in Turkey and Morocco. Therefore, this study aims to understand the causes of the catastrophic earthquakes in Turkey and Morocco. The main objective is to analyze the strengths and weaknesses of the disaster management stages during the 2023 earthquakes in Turkey and Morocco, and to compare these with the situation in Bangladesh to better understand potential earthquake risks there. Moreover, the study seeks to develop a framework for Disaster Learning. It follows a qualitative research methodology, with most of the necessary data gathered from existing literature and Key Informant Interviews. The findings suggest that infrastructural vulnerabilities and noncompliance with land use regulations were significant causes of the catastrophic damage in Turkey and Morocco, which are also relevant to the earthquake risks in Bangladesh. Key strengths identified in Turkey include the availability of open spaces for emergency services, wide roads, modern equipment, skilled manpower, military-civilian coordination, and a robust humanitarian response—all areas where Bangladesh has significant deficiencies. Lessons from this study reveal that climatic conditions and debris management could pose major challenges for Bangladesh in the event of a significant earthquake.

National risk assessment of Italian school buildings: The MARS project experience

Strategic buildings, such as schools, play a crucial role in civil society. They are essential not only for the well-being of communities but also for their significance during the emergency and recovery phases following an earthquake. Reliable risk assessment is a powerful tool for implementing effective mitigation strategies. While considerable work has been already done in the literature to develop fragility curves and risk studies for residential buildings, there remains a noticeable gap in addressing risk assessment for school portfolios. As part of the 2019–2021 MARS (Seismic Risk MAps) project, funded by the Italian Civil Protection Department and involving the ReLUIS consortium along with the EUCENTRE foundation, a specific task was dedicated to evaluating seismic risk for the Italian school buildings. In this context, eight research units combined their expertise to develop a consensus-based vulnerability model, known as the “School-MARS model”. This model integrates fragility curves based on various approaches (i.e. empirical, mechanical-analytical, mechanical-numerical and hybrid) and is tailored to archetypes representative of the Italian school buildings. The main goal of the paper is outlining the methodology used to define the “School-MARS vulnerability model”. Moreover, the paper demonstrates the application of the latter for performing intensity-based and time-based risk analyses. Specifically, the results are presented in terms of damage distribution and usability ratings expected for the entire stock of Italian school building. Notably, these results indicate that approximately 26 % of Reinforced Concrete (RC) buildings and 31 % of Unreinforced Masonry (URM) structures may become unusable due to potential earthquakes expected in the next 50 years.

Analisis Deformasi di Lampung dan Selat Sunda berdasarkan Data GNSS tahun 2018 hingga 2021

The Lampung Province and Sunda Strait have a seismic gap zone with the potential for major earthquakes in the future. This study analyzes the deformation occurring in this region using continuous Global Navigation Satellite System (GNSS) station data from Indonesia Continuously Operating Reference Station (InaCORS) and Sumatran GPS Array (SuGAr) from 2018 to 2021.5. The GNSS data was processed using the Bernese 5.2 scientific software, applying least squares for velocity changes and statistical tests to analyze significance. The data processing was carried out in two schemes: the first scheme covering 2018-2020, and the second covering 2019-2021. The results of the deformation analysis from 2018 to 2021, using two continuous GNSS data processing schemes, showed velocity changes relative to the Sundaland Plate ranging from ~2 mm/year to ~20 mm/year. In the eastern region of the Sumatra fault, the velocity changes were smaller, around ~5 mm/year, due to the minimal influence of tectonic activity. However, in the Sunda Strait region, the deformation was influenced by volcanic activity. The deformation occurring in Lampung Province and the Sunda Strait, based on GNSS velocity changes, significantly contributes to tectonic and volcanic activities.

Tracing the sources of paleotsunamis using Bayesian frameworks

Paleotsunami deposits provide a compelling record of these events, including valuable insights into their recurrence and associated magnitudes. However, precisely determining the sources of these sedimentary evidence remains challenging due to the complex interplay between hydrodynamic and geological phenomena and the intricacy of the processes responsible for forming and preserving tsunami deposits. Here, we introduce a novel approach that employs Bayesian inference methods to divide the complex tsunami process into segments and independently handle uncertainties, thereby enabling more precise and comprehensive modelling of the sources. We provide a list of potential earthquake scenarios with different likelihoods instead of a single best fit. Based on this method, we calculated that the source of the 869 Jogan earthquake had a magnitude ranging from Moment Magnitude 8.84 to 9.1 (within one standard deviation) with different slip distributions along the Japan Trench. Our results reaffirm that the Jogan event had a similar order of magnitude to the 2011 Tohoku-oki tsunami and enhanced the applicability of paleotsunami deposits to hazard assessment.

Shallow Creep on the Laohushan Segment of the Haiyuan Fault, Northeastern Tibetan Plateau, Detected With Dense Near‐Field GPS Measurements

AbstractWhile shallow creep along the Haiyuan fault is a key element in estimating earthquake potential, both the creep rate and spatial distribution inferred from InSAR and repeating earthquakes are still controversial. In this study, we resolve two potentially separated creeping patches along the Laohushan fault (LHSF) based on dense near‐field GPS measurements of 39 stations. The largest creeping patch, which extends ∼20 km along‐strike and ∼9 km down‐dip with a slip rate of 4.2 mm/yr, spatially correlates with seismicity, especially repeating earthquakes. The locked segment is capable of producing an earthquake of Mw 7.3 ± 0.1, with moment rate of (1.08 ± 0.39) × 1017 N⋅m/yr, possibly following the cycle since the 1092 M8 event. The lack of GPS measurements in the near‐field makes it unclear whether the 8 km section between these two patches is slowly creeping below detection threshold or has relocked due to change in environmental condition.

Newly Discovered NE-Striking Dextral Strike-Slip Holocene Active Caimashui Fault in the Central Part of the Sichuan-Yunnan Block and Its Tectonic Significance

The Sichuan-Yunnan block is a tectonically active region in China, with frequent large earthquakes occurring in and around it. Despite most earthquakes being concentrated along boundary faults, intraplate faults also have the potential to generate damaging earthquakes. Remote sensing makes it possible to identify these potential earthquake source faults. During an active fault investigation in the Liangshan area, a distinct lithological boundary named Caimashui fault was found. The geometric distribution and kinematic parameter of the fault is crucial for assessing seismic hazards and understanding the deformation pattern within the Sichuan-Yunnan block. The Caimashui fault is mapped with remote sensing interpretation, a field survey, and UAV measurement. Through trenching and Quaternary dating, the Late Quaternary active characteristics of the fault are studied. The fault is a Holocene active dextral strike-slip fault with a reverse component, exhibiting a dextral strike-slip rate of ~0.70 ± 0.11 mm/a. Paleoseismic investigation shows that the last surface rupture event of the Caimashui fault occurred later than 4150 ± 30a BP, with a magnitude of M ≥ 7.0. The fault may act as a secondary splitting fault, absorbing the deformation caused by various sinistral strike-slip rates of the boundary faults and the potential energy from the counterclockwise rotation of the Central Yunnan micro-block.

Design of E.R. Building At Ct Arsa Palu Hospital With Liquefaction Potential

This design hospital building is planned to be built in the city of Palu. Palu City has high earthquake potential, has history of liquefaction, tsunami and landslides disasters. Thorough design is needed so that this hospital building still become a place for health services after a disaster occurs. The building was designed using the Special Moment Resisting Frame Structure system based on the SNI. Earthquake load analysis uses the response spectrum method based on Earthquake Resistance Planning Procedures (SNI 1726:2019). This concept obtains structure design that meets SNI and still strong in strong earthquake and liquefaction. Analysis has been carried out and it was found that the potential for liquefaction to occur at a depth of 1.5 M to 4.5 M so that the foundation chosen was 4 piles with a diameter of 40 cm, a depth of 6 meters per pile cap. From the results of calculations, it shows that the structure of the emergency room building at CT Arsa Palu Hospital is safe from an analytical perspective.

Physics-based assessment of earthquake potential on the Anninghe-Zemuhe fault system in southwestern China

The seismic hazard of a fault system is controlled by the maximum possible earthquake magnitude it can host. However, existing methods to estimate maximum magnitudes can result in large uncertainties or ignore their temporal evolution. Here, we show how the maximum possible earthquake magnitude of a fault system can be assessed by combining high-resolution fault coupling maps with a physics-based model from three-dimensional dynamic fracture mechanics confirmed by dynamic rupture simulations. We demonstrate the method on the Anninghe-Zemuhe fault system in southwestern China, where dense near-fault geodetic data has been acquired. Our results show that this fault system currently has the potential to generate Mw7.0 earthquakes with maximum magnitudes increasing to Mw7.3 by 2200. These results are supported by the observed rupture extents and recurrence times of historical earthquakes and the b values of current seismicity. Our work provides a practical way to assess the earthquake potential of natural faults.

The 2023 Mw 6.8 Morocco earthquake induced atmospheric and ionospheric anomalies

Earth observations through Global Navigation Satellite System (GNSS) and Remote Sensing (RS) technologies play a significant role in natural hazard surveillance, particularly in the context of earthquake prediction and detection. This study introduces a distinctive Deep Learning (DL) based approach to identify ionospheric and atmospheric precursors, utilizing data from multiple satellite sources and provides a comprehensive analysis of spatiotemporally varying precursors, contributing to the understanding and monitoring of seismic activity in earthquake-prone regions. In our investigation of the Morocco earthquake on September 08, 2023 (Mw 6.8), we analyzed various precursors including Total Electron Content (TEC), Air Pressure (AP), Relative Humidity (RH), Outgoing Longwave Radiation (OLR), and Air Temperature (AT). Our study aims to identify a synchronized anomalous window of potential earthquake precursors using Standard Deviation (STDEV), Continuous Wavelet Transform (CWT), and Long Short-Term Memory Inputs (LSTM) network. Both statistical and deep learning methods revealed abnormal fluctuations as precursors occurring within 8–9 days before the earthquake near the epicenter. Additionally, we detected geomagnetic anomalies in the ionosphere 6 days prior to and 4 days after the earthquake, coinciding with active geomagnetic storm days. This research underlined the importance of combining multiple earthquake precursors using statistical and deep learning approaches to support the understanding of the Lithosphere-Atmosphere-Ionosphere-Coupling (LAIC) phenomena.

Reappraising the seismogenic potential of a low-strain rate region: Active faulting in the eastern Siena Basin (southern Tuscany, Italy)

We investigated the active tectonics and earthquake potential of the eastern Siena Basin, a slowly deforming portion of southern Tuscany in the inner Northern Apennines. This region hosts several historical settlements and valuable cultural heritage, but also frequent background seismicity and rare damaging earthquakes in the Mw range 5.0–6.2. We describe in detail an active, capable, and seismogenic fault system that we identified in the eastern Siena Basin, a few kilometers south-east of the city of Siena, thanks to the presence of an active quarry (Cava Capanni) that exploits travertines of Middle Pleistocene-Holocene age. Travertines are unique rock masses that may preserve living evidence of active and seismogenic faulting, thus providing remarkable seismotectonic insight. The active fault system consists of at least two segments rupturing travertines younger than 45 ka, with a cumulative vertical displacement of 111 cm, and an estimated minimum slip rate of 0.02–0.03 mm/y. We maintain that this displacement is the result of at least three coseismic movements accompanied by clastic dykes injected within the fault damage zone due to liquefaction phenomena. The fault system is seen to extend east of the quarry, affecting Pliocene and Mesozoic deposits.The Cava Capanni fault system is evidence of a poorly understood but potentially seismogenic tectonic mechanism of regional extent. Its orientation and kinematics are compatible with the activity of faults that are oriented obliquely or orthogonally to the main chain axis, in contrast with the setting of the axial and outer zone of the Northern Apennines, where extension and compression are accommodated by Apennines-parallel faults.

Triggered and recurrent slow slip in North Sulawesi, Indonesia

Nearby faults interact with each other through the exchange of stress. However, the extent of fault interaction is poorly understood. In particular, interactions may lead to slow-slip activity, resulting in episodes of transient surface motion. Our study concentrates on Northwest Sulawesi (Indonesia), which hosts two fault zones with potential for major earthquakes and tsunamis: the strike-slip Palu-Koro fault and the Minahassa subduction zone. Thanks to a 20-year-long effort in geodetic monitoring, we are able to identify multiple periods during which surface velocities deviate from their interseismic trend. We use a Bayesian methodology with forward predictions of slip on the two fault interfaces to match the observations following the 2018 Mw7.5 Palu earthquake, and infer that both deep afterslip on the Palu-Koro fault and slow slip on the Minahassa subduction interface have caused the observed transient surface motion. This finding represents the first recording of a slow slip event on the Minahassa subduction interface. We also infer that the subduction interface and the strike-slip fault are likely interacting on a regular basis.

Are maximum magnitudes of induced earthquakes controlled by pressure diffusion?

There is an ongoing discussion about how to forecast the maximum magnitudes of induced earthquakes based on operational parameters, subsurface conditions and physical process understanding. Although the occurrence of damage caused by induced earthquakes is rare, some cases have caused significant economic loss, injuries and even loss of life. We analysed a global compilation of earthquakes induced by hydraulic fracturing, geothermal reservoir stimulation, water disposal, gas storage and reservoir impoundment. Our analysis showed that maximum magnitudes scale with the characteristic length of pressure diffusion in the brittle Earth's crust. We observed an increase in the nucleation potential of larger-magnitude earthquakes with time and explained it by diffusion-controlled growth of the pressure-perturbed part of faults. Numerical and analytical fault size modelling supported our findings. Finally, we derived magnitude scaling laws to manage induced seismic hazard of upcoming energy projects prior to operation. This article is part of the theme issue 'Induced seismicity in coupled subsurface systems'.

Earthquake detection in mountainous homes using the internet of things connected to photovoltaic energy supply

The North Sumatra region is an area with the potential for earthquakes originating from volcanic and oceanic eruptions which have resulted in many fatalities. Therefore, through the application of automatic monitoring and control system technology connected to the internet of things (IoTs), it is the right solution to provide efforts to increase security for residents of the house to always be vigilant. The security enhancement method referred to in this study is a home security system protection system by anticipating earthquakes. The advantage of this tool is that it applies a notification security system method with a sensitivity sensor which is automatically sent via email and sonor buzzer which also acts as sound vibrations due to an earthquake. The test results show that when a vibration occurs, the system will send a short email message to the user's smartphone so that the user will receive an email in the form of a warning message that the state of the house has an earthquake and the light-emitting diode (LED) interrupts and the buzzer is also on so that the alarm sounds which has been integrated into IoT. Then an integrated security monitoring system using the web can be monitored in real time.

Active faults along Indonesia’s first high-speed rail line

Abstract The cities of Jakarta and Bandung, two vital hubs in the western part of Java, are now connected by a high-speed rail line. However, potential earthquake hazards arise as the line intersects two active faults in West Java. To address this concern, we conducted a detailed geomorphological analysis using high-resolution DEM data (8-meter resolution) combine with 30-m resolution data to locate fault lines along the rail infrastructure. In the north, the line intersects the West Java back-arc thrust, while in the south, it crosses the junction of the Lembang Fault and Cimandiri Fault in Padalarang. However, young deposits and vegetation still could obscure fault traces in specific areas observed from high-resolution DEM data. To overcome this challenge, we employed UAV drone mapping to capture finer geomorphology details. This information then combined with paleoseismology trenching to uncover the active structural features. The aim is to enhance the railway’s resilience; and build monitoring and early warning systems for the high-speed train operation system to seismic events.