Abstract:Hot dry rock(HDR)is a strategic clean energy resource with considerable advantages,including abundant reserves,stable power output,and renewability.However,induced seismicity remains a primary challenge in HDR development and represents a critical bottleneck,leading to the termination or postponement of several international projects.This study systematically reviews the composition,typical case studies,and existing problems of current traffic light systems(TLS)for seismic risk mitigation during HDR hydraulic stimulation.Based on the principles of selecting parameters that directly relate to seismogenesis control,are easily measurable,and facilitate systematic management,we have proposed fundamental criteria for determining TLS decision parameters and threshold settings.Subsequently,we developed an enhanced TLS framework incorporating six key parameters,namely,earthquake magnitude,b-value,peak ground velocity(PGV),injected fluid volume,injection rate,and wellhead injection pressure.We identified the major challenges facing TLS implementation and suggested future research directions,aiming to provide references for induced seismicity risk management in HDR,shale gas,and other energy sectors involving hydraulic fracturing,supporting national strategic initiatives for deep-resource exploitation.

Abstract:Research on early warning systems for natural disasters are necessary to promote the modernization of national security systems and capabilities.Therefore,this study used CiteSpace bibliometric software to select the China National Knowledge Infrastructure(CNKI)and Web of Science as the Chinese and foreign databases,respectively.The co-occurrence map of keywords,keyword clustering map,and keyword burst map of domestic and foreign research on natural disaster early warnings were then analyzed.In addition,the frontier hotspots and development trends of early warning research at home and abroad were addressed and the differences in research in this field between China and foreign countries were compared.This study reveals that communication and exchange in natural disaster early warning research between China and the international community should be strengthened,international cooperation in early warning should be promoted,public awareness and disaster prevention and mitigation ability should be improved,and modernization of the national security system and capabilities should be advanced.

Abstract:The inversion of pre-stack wave impedance is closely related to the parameters such as incident angle,P-wave velocity,S-wave velocity,and density.Compared to post-stack inversion,the inclusion of both P-to S-wave velocities allows for the derivation of more comprehensive elastic parameters.This enhances the ability to differentiate lithology and hydrocarbon-bearing formations,providing a more accurate foundation for drilling decisions.Shear-wave velocity data are particularly critical for pre-stack impedance inversion.However,in the T block,only one set of S-wave logging data is available,and its reliability is uncertain due to factors such as mud invasion.As a result,accurately estimating shear-wave velocity especially its hydrocarbon-sensitive variations are a crucial step in elastic parameter inversion for pre-stack analysis.Given the characteristics of the main target formations,KT-Ⅰ and KT-Ⅱ,in the T block,porous carbonate reservoirs with strong heterogeneity,this study proposes a shear-wave velocity estimation method based on an empirical Poisson's ratio model.This approach effectively enhances the sensitivity of pre-stack seismic attributes to hydrocarbons.Through test processing,parameters of the Poisson's ratio-based estimation model were selected to the geological conditions of the T Block.A reservoir-sensitive threshold for the vP/vS ratio was identified as 1.8.Based on the vP/vS parameters of KT-ⅡG formation,the thickness of effective reservoir is predicted.The predicted thickness is more than 85％consistent with well verification,which provides a strong support for exploration and evaluation of well location deployment.

Abstract:To ensure stable operation of Anhui seismic monitoring network,a comprehensive review of the operational status of 31 participating stations from 2020 to 2024 was conducted.The operational efficiency of the stations was evaluated reasonably by analyzing station uptime rates,fault frequency,and cumulative downtime.Common faults were categorized into four major types:communication systems,power supply systems,observation instruments,and other factors,and twelve subcategories.Analysis indicated that 29 of the 31 evaluated stations maintained an annual average operational rate exceeding 99％through the five-year period.The vast majority of the faults were detected and resolved within 24 hours,demonstrating overall sound operation of the observation systems.Power supply and communication system failures constituted the primary fault types affecting seismic observation stations,accounting for 73％of all incidents.Recommendations include developing an AI-powered station operation and maintenance model and an online fault diagnosis platform to automate fault alerts,rapid diagnostics,and solution generation;strengthening duty shifts during July to September and implementing proactive lightning and flood prevention measures;and optimizing spare equipment allocation strategies and enhancing the maintenance capabilities of grassroot personnel of provincial operation centers.

Abstract:The integrity of seismic monitoring data is an important link in the development of seismic monitoring and forecasting.This study considers the data integrity guarantee of the Yanqing seismic array as the research object and discusses how to use a Python automation program to complete the design and application of the software.The design idea and practical application cases of the program are introduced in detail.The problem of missing station record data is solved automatically,and the efficiency and accuracy of the data integrity guarantee are improved.The software has been applied to related work on the completion of the Yanqing seismic array data.

Abstract:In this study,we collected and organized observational data on soil radon concentrations from across seven active-fault monitoring lines in the northern Hainan region from 2020 to 2022.The average concentration,anomaly threshold,and number of measurement points exceeding the soil radon concentration threshold in the seven monitoring lines over this period were calculated,and the characteristics of the concentration changes in each monitoring line during the three years were analyzed.The results indicated that from 2020 to 2022,the concentration changes in soil radon emitted from the seven monitoring lines were consistent with the characteristics of soil radon concentration changes across active faults.Except for the 2020 Jinkang Road survey line,which had no measurement points exceeding the threshold,the observed values for the other survey lines exceeded the threshold every year.However,the magnitude of the exceedance was relatively small,as was the number of measurement points exceeding the threshold.The activity risk of the three active faults where the seven survey lines are located is not high,and the possibility of destructive earthquakes occurring is relatively small.This is the first study in which a spatiotemporal database of radon concentrations in the soil around active faults in the northern Hainan region has been established,and the background range of soil radon near active faults(8 500～33 000 Bq/m3)has been defined.Our findings provide a baseline reference for subsequent earthquake precursor identification.

Abstract:Against the backdrop of cultural and tourism integration,there is an urgent need to explore innovative paths to popularize science for earthquake prevention and mitigation.Earthquake prevention and mitigation venues in Hebei Province are classified into memorial and science popularization categories.However,they suffer from issues such as small numbers,uneven geographical distribution,insufficient socialized management,and fewer updates to exhibition items.The popular science content includes earthquake disasters,earthquake relief,and post-disaster reconstruction around destructive earthquake events,popular science knowledge such as basic earthquake knowledge,earthquake prevention and avoidance skills,earthquake prevention and disaster reduction work,and earthquake prevention and disaster reduction product publicity.The main target audience for science popularization is young people.Emphasis is placed on enhancing the impact of promotion through offline activities such as research studies and exhibitions,and online activities such as live broadcasts and virtual lectures.Meanwhile,earthquake prevention and mitigation venues in Hebei Province generally have a low degree of cultural and tourism integration,with insufficient tourism development.The integrated development of earthquake prevention and disaster reduction education bases and the tourism industry should be promoted by focusing on the top-level design of earthquake science popularization and cultural tourism integration,protecting and using existing earthquake relics and site resources,while actively developing earthquake prevention and disaster reduction tourism routes.

Abstract:Time-frequency analysis is vital in seismic data processing,and the need for high-resolution technique is intensifying as exploration advances.This paper traces the evolution of time-frequency methodologies beginning with the inherent limitations of traditional methods,particularly between temporal and spectral resolution.Recent progress is examined along two major fronts:fractional-domain analysis and compressive sensing.Fractional-order methods introduce fractional calculus to achieve more nuanced representation of seismic signals,thereby exposing their complex structural attributes compressive sensing theory uses signal sparsity algorithms optimization to enable efficient re-construction and enhanced time-frequency characterization.In parallel,deep learning has emerged as a transformative tool,offering robust representation and generalization capabilities for sparse analysis,denoising,signal enhancement,and reservoir prediction.These advances mark significant breakthroughs in seismic exploration.This paper concludes with a synthesis of current methodologies and a perspective on future research directions,aiming to provide comprehensive reference for the continued development of seismic exploration technologies.

Abstract:Ground resistivity is an earthquake prediction method that is influenced by various factors such as rainfall,changes in the environment surrounding the observation station,and observation system failures.Some forms of interference with seismic monitoring data are easily confused with seismic precursors.A ZD8BI digital geoelectric instrument in the NS and EW channel directions is used to determine the ground resistivity at the Guzhuang Observation Station of the Nantong Central Station.A turning point in the daily average ground resistivity was identified,decreasing from February to April 2022 and slightly increasing from April 18,2022,differing from the normal annual variation.The background information from the Nantong Central Station was examined in depth;the environment surrounding the geoelectric observation site were analyzed.The equipment status and stability of the observation site calibration were determined.The meteorological factors as well as typical monitoring data interferences and their causes were studied.The observed resistivity data from the geoelectric field were compared with those and from other stations in Jiangsu,and anomalies were analyzed to determine whether the differences between stations were caused by rainfall.This study provides a reference for future data analysis and determining seismic activity trends around ground resistivity stations.

Abstract:To clarify the impact of environmental disturbance events on deformation observations,this study analyzed the correlation between abnormal deformation data recorded at Yixian seismic station from 2014 to 2023 and corresponding load disturbances using a three-dimensional quantitative model.The findings are as follows:Seven instances of abnormal deformation at Yixian seismic station were confirmed to be directly triggered by load disturbances;Environmental disturbances have a significant impact on the SS-Y extensometer data,with a contribution rate of 100％,whereas their impact on the DSQ water pipe inclinometer data is much lower at 28.37％;Abnormal responses in the cave-based deformation instruments are most pronounced when the disturbance source lies within 500 m and the applied load reaches 1000～1500t.

Abstract:At 22:15 Beijing Time on December 8,a magnitude 7.5 earthquake occurred offshore of eastern Honshu,Japan.Following the event,the Strong Motion Observation Center of the Institute of Engineering Mechanics,China Earthquake Administration,promptly initiated a rapid emergency response.Personnel were mobilized to collect,process,and conduct a preliminary analysis of the earthquake's strong-motion records.Emergency products,including maps of instrumental seismic intensity and peak ground acceleration(PGA)distribution,were rapidly generated.Preliminary analysis results indicate that within a 200 km radius around the epicenter of this earthquake,there have historically been 21 earthquakes with magnitudes of 7.0 or greater,including 3 with magnitudes of 8.0 or greater.A total of 872 recorded waveforms had a PGA exceeding 10 cm/s2.The calculated instrumental seismic intensity,based on the Chinese Seismic Intensity Scale(GB/T 17742-2020),ranged from 1.0 to 8.6 degrees.Station AOM010 recorded the highest intensity value of 8.6 degrees at an epicentral distance of 102.7 km,while station AOMH06,with the closest epicentral distance of 78 km,recorded an intensity of 7.5 degrees.The rapid production of products from strong motion observations aids in the swift assessment of post-earthquake situations,provides crucial support for disaster evaluation,emergency decision-making in affected countries,and offers immediate scientific backing for Chinese government agencies in formulating international emergency rescue plans for major earthquakes and assessing the potential impact of overseas seismic events on China.

Abstract:This research focuses on an anomaly observed by the radon-thorium analyzer in Wen'an well.It exhaustively records the workflow of grassroots water stations to verify fluid anomalies,including basic data collection,instrument condition inspection,and investigation of the surrounding environment.Through on-site sampling,the hydrochemical data of Wen'an well are obtained for the first time,determining it to be HCO3—Na+type water.The analysis shows that the recharge sources include mixed shallow-surface substances and deep-groundwater recharge,with active water-rock interactions occurring,and no ionic equilibrium being reached.The study comparatively analyzes the underground fluid data,seismic activity,hydrochemical data,parallel observation data,and morning-afternoon comparative observation data of Wen'an well,ruling out influences such as instrument malfunctions,environmental interference,and meteorological factors.It is comprehensively determined that the high-value radon anomaly in Wen'an well present since May 17,2024 may be related to the enhanced regional stress state.This research provides technical support and analytical ideas for the verification of earthquake precursor anomalies,and has important reference value for research in underground fluid disciplines,earthquake monitoring,and early warning systems.

Abstract:Waveform macro-anomalies refer to false single-station triggers caused by non-seismic events that can lead the processing system to misinterpret data.When multiple stations experience coupled waveform macroanomalies,they can easily result in false alarms.To enhance the operational quality and data reliability of the Shaanxi earthquake early warning network,we collected various abnormal waveforms encountered during the trial operation of the network.These anomalies are typically categorized into five types:zero drift,spike,gourd-shaped,step,and jump.By analyzing continuous waveform data from the low-noise period each early morning,combined with spectral analysis and noise characterization,we identified the typical time-and frequency-domain manifestations of each anomaly type and explored their potential causes.Based on these findings,specific recommendations for on-site inspection and operational maintenance were proposed for different anomaly types.The implementation of this research effectively improves the data quality of the Shaanxi warning network,helps prevent false triggers of the early warning system,ensures its stable and reliable operation,and provides a foundation for further research on the automated identification of abnormal waveforms.

Abstract:With cosponsored by the committee of earthquake prediction(CEP)and the committee of earthquake monitoring(CEM)of Seismological Society of China(SSOC)as well as China Earthquake Networks Center(CENC),the 50th anniversary of the Haicheng earthquake and the 13th annual conference of China Earthquake Prediction Forum(CEPF)had been successfully held on July 11-15,2025 in Beijing National Convention Center.About 200 participants from more than 50 institutes and universities including Peking University,Dalian University of Technology,Henan Polytechnic University,North China University of Water Resources and Electric Power,Southern University of Science and Technology,Tianjin University,Zhejiang University,University of Science and Technology of China,University of Chinese Academy of Sciences,China University of Mining and Technology(Beijing),and Institute of Geology and Geophysics,Institute of Advancing Precision Instrumentation,National Space Science Center,Institute of Mechanics,Institute of Tibetan Plateau Researth of Chinese Academy of Sciences,as well as the Institutes of China Earthquake Administration,attended this conference to warmly discuss the topics focusing on the prediction processes of the Haicheng earthquake,earthquake monitoring,earthquake prediction,the application of new technology and new approaches to earthquake prediction,case studies on recent events and public education of historical strong earthquakes through 14 scientific sessions.Academician He Manchao and Academician Ni Sidao were invited to present keynote reports on earthquakes and the measurement of Newtonian force of faults and the research progress of extremely shallow earthquakes respectively for the conference.There were 46 researchers showed research progress by oral presentations covering 14 conference sessions,and more than 30 young researchers presented their research progress through posters,where 6 presenters of well-designed posters obtained the certifications of oral presentation in the next annual conference.About 70 papers were collected before conference and will be published in supplementary issue of Seismological and Geomagnetic Observation and Research after peer reviewing.More than 120 types of instruments from 22 manufactures present the technique advancement of monitoring networks.Prof.Gao Mengtan and Prof.Shen Jun were invited to carry out the field training and public education on rupture zone of 1679 Sanhe-Pinggu great earthquake along Xiadian fault.

Abstract:On March 29,2022,an Ms 4.3 earthquake occurred in Danling County,Meishan City,Sichuan Province.This event took place near the Xiongpo anticline at the southern margin of the Sichuan basin,with a focal depth of 3.5～5.5 km and a moment magnitude(MW)range of 4.06～4.15.To investigate the seismogenic structure of this earth-quake,we conducted integrated analyses of the regional historical seismicity and major fault activity.We referenced the focal mechanism solutions inverted by the Sichuan Earthquake Agency,examined seismic rupture characteristics and stress field orientation,and combined high-resolution satellite imagery with Digital Elevation Model(DEM)data to analyze tectonic deformation and fault activity.The seismic profile data were also used to identify key fault zones and delineate their geometric and kinematic features.The research revealed that the focal mechanism solution of the March 29,2022,Ms 4.3 earthquake indicates left-lateral strike-slip faulting.Nodal Plane Ⅰ(NW-striking,dip angle 79°～87°)is considered to be the more probable seismogenic plane,the orientation of which is nearly perpendicular to the regional dominant structure,the NE-trending Xiongpo anticline-Pujiang-Xinjin fault.This plane represents a high-angle,near-vertical tear fault(strike-slip fault),formed by differential thrusting of adjacent blocks due to stress transfer following the 2008 Wenchuan earthquake and the 2013 Lushan earthquake.The spatial distribution of the aftershocks provides evidence to indicate that the Danling earthquake probably activated local stress adjustments along the Pujiang-Xinjin fault.This event highlights the control of stress transfer in orogenic forelands over the activity of hidden faults in intraplate tectonic settings,thereby providing new insights for assessing seismic hazards at basin margins.

Abstract:The Chengdu seismic monitoring station network was selected as the study object.The six outstanding problems were systematically analyzed.The ideas and countermeasures for the optimization and integration of the station network of"global co-ordination and step-by-step implementation"were developed:by encrypting the scientific array observation of potential seismic risk areas,implementing geophysical multi-disciplinary and multi-term collaborative observation and integration of resources at the same site of cities and counties,eliminating non-standard equipment and transforming old facilities,carrying out site standardization transformation and intelligent technology upgrading,integrating the city's seismic monitoring and emergency command system,and deeply sharing provincial monitoring data resources,etc.,to build a new modern seismic monitoring network.The optimization scheme focuses on improving the decision-making ability of earthquake prevention and disaster reduction and the integration degree of professional station network,which can provide a reference for the upgrading of earthquake monitoring station network in the same type of cities,and effectively support the modernization of earthquake prevention and disaster reduction and the development of urban resilience construction.

Abstract:From 2021 to 2022,the water level in the Yingxiu well showed a large anomalous annual decline.In this study,we analyzed the correlation between rainfall and the water level and conducted a quantitative exclusion analysis of the impact of rainfall on the water level.The environment surrounding the observation site were also investigated,geochemical tests were conducted on water samples,and stress changes in the wellbore aquifer system were analyzed to determine the abnormal cause of this annual change.The results showed that the annual change in the water level in Yingxiu well dropped significantly in 2022,and this was controlled by both rainfall factors and other factors.At the beginning of 2022,the parameters of the aquifer in the observation period fluctuated significantly,indicating that the annual water level gradient was related to the tectonic static stress of the aquifer that may be related to changes or adjustments in the regional tectonic stresses before and after a series of earthquakes with a magnitude 6 occurring from June to September 2022.

Abstract:In this paper,we briefly conducted an observation overview of the Caoping electric field in Lixian County,collected observation data for graphical analysis,and compared and measured the parameters of observation quality(correlation coefficient and difference).The conclusions of the study follow:The newly established observation system operates well and produces high-quality data internally;Two observation systems can observe simultaneously without interfering with each other and can receive external abnormal information,such as geomagnetic storms;The solid non-polarized electrode selected for the main observation system better correlation.This article serves as a reference for electrode layout and electrode selection in the observation of ground electric fields at other stations.

Abstract:The observation data from the Luoci geoelectric observatory station were studied.The main sources of data interference were identified and analyzed using the observation data from a geoelectric observatory station.The main sources of data interference were electrode lead damage,water pump leakage in the hot spring operators,large-scale infrastructure construction,and rainfall.The typical changes in these four main interference sources were investigated,and solutions were proposed to reduce data interference.The quality of the geoelectric observatory station observations was evaluated using correlation analysis and differences between observations.Methods of increasing observation quality work are summarized.The characteristics of the Luoci geoelectric observatory station data were compared with those obtained at the nearby Yuanmou Julin geoelectric observatory station to determine their differences.The reasons for the differences between the two geoelectric observatory station observation records were identified.This study provides a reference for helping station staff understand geoelectric observatory station observation data,identifying data noise,and analyzing seismic data.A scientific basis is provided for upgrading geoelectric observatory stations.