Geological Disaster Monitoring Research Articles

РОЛЬ ГЕОДЕЗІЇ В МОНІТОРИНГУ ГЕОЛОГІЧНИХ ПРОЦЕСІВ ТА ПРИРОДНИХ КАТАСТРОФ ДЛЯ ПОПЕРЕДЖЕННЯ НЕГАТИВНИХ НАСЛІДКІВ

The purpose of the study is to analyze the contribution of geodetic methods and technologies to the detection, assessment and monitoring of geological processes and natural disasters in order to minimize their dangerous consequences for society and the environment. Research methodology. remote sensing of the Earth, the use of satellite images and aerial photography to collect data on geological processes and the state of the environment. Method of geodetic monitoring. tracking changes in the position of objects over time, which allows detecting soil micromovements, potential landslides and other deformations. GIS technologies (geoinformation systems). Integrating and analyzing geodata to model geological processes and natural disasters, creating thematic maps that can display potential risks and assist in response planning. The results. The task of monitoring geological changes and natural disasters using cartographic methods designed to work with many users has been set and solved, significantly increasing the level of safety and prompt response to emergency events. An important aspect in the implementation of geodetic observations is the use of an integrated approach that includes field research, geodetic analysis and remote sensing data. This ensures higher accuracy and efficiency of monitoring. Scientific novelty. The research focuses on identifying effective approaches to the collection, processing and analysis of spatial data that can be used for timely prediction and prevention of catastrophic events, as well as for emergency response planning. The developed adapted model of risk assessment of natural emergency situations, which is based on the analysis of terrain conditions at various times, allows to increase the accuracy of risk assessments. Practical significance. The use of remote monitoring methods ensures prompt receipt of information and the possibility of taking measures for nature protection in a timely manner. The conceptual model made it possible to identify the factors of man-made influence, assess the condition of soils and vegetation, as well as perform a cartographic analysis of disturbed lands in order to develop measures for their restoration. The created thematic maps of the dynamics of disturbed lands serve as a basis for making management decisions aimed at systematic restoration and reduction of negative man-made impacts, opening up new perspectives for the use of interactive technologies in geodesy.

Editorial: Mine engineering geological disaster forecasting, monitoring, and prevention

Editorial: Mine engineering geological disaster forecasting, monitoring, and prevention

Assessment of Spatial Heterogeneity of Soil Moisture in the Critical Zone of Gully Consolidation and Highland Protection

The Gully Consolidation and Highland Protection (GCHP) project (such as for gully head landfills), a consideration of soil and water conservation measures, has been explored and developed continuously in recent decades in the Chinese Loess Plateau. Using high-precision images taken by drones to extract the topography of the basin, the changes in vegetation and land use were also analyzed. The observation of soil moisture in the critical gully head area of the GCHP was carried out. The results indicated that the critical zones of the GCHP project implementation include the gully head landfill, the gully, and the highland farming area. The soil moisture of the landfill area was 6.91% and 23.61% higher than that of the gully and farming area, respectively, with obvious spatial heterogeneity. The soil sand content in the gully head landfill area was higher than that in the gully area and the agricultural area of the plateau. The main reason for the high soil moisture in the gully head landfill area is that the terrain at the outlet is low, and it is at the lowest point of the whole basin. Analyzing the spatial distribution of soil moisture can point out the direction for the monitoring, prevention, and treatment of geological disasters, such as landslides and debris flow, induced by water erosion. This study will help to understand in detail the spatial heterogeneity and influencing factors of soil moisture under the implementation of the GCHP and improve the GCHP project management system.

THE KEY TECHNOLOGIES OF GEOLOGICAL DISASTER DYNAMIC MONITORING BASED ON NAP-OF-THE-OBJECT PHOTOGRAMMETRY

Abstract. Dynamic monitoring of geological hazards is an important project. Photogrammetry plays an important role in geological hazard monitoring, because of its advantages of convenient data processing, low cost, non-contact, direct texture information and intricate 3-D real scene model. For the traditional photogrammetry can not meet the needs of dynamic monitoring, based on multi-period nap-of-the-object photogrammetry, this paper obtains high-precision images and produces a refined 3D real scene model to carry out the dynamic monitoring of geological disasters. A deformation detection method of geological hazards based on the comparison of three-dimensional model differences is proposed to locate the position with serious deformation. Then, based on the severely deformed area, the multi-period generalized orthophotos are produced, and the image feature matching is used to find the homonymous points between the generalized orthophotos. The two-dimensional and three-dimensional coordinate forward and inverse transformation of the generalized orthophotos are used to calculate the size and direction of the deformation displacement, analyze the deformation trend of geological disasters, and finally realize accurate monitoring of the deformation trend of geological disasters. The results show that the deformation area detection method proposed in this paper is simple and effective, which can quickly find the deformation position. The deformation trend prediction based on multi-period generalized orthophotos is feasible, and the displacement with deformation of 3CM can be accurately pointed out.

Slope deformation monitoring and early identification of disasters in debris flow source area of Baini River, Dongchuan District, China

Dongchuan District is one of the most densely distributed regions of geological disasters in the world. Geological disasters such as debris flows and landslides are serious threats to the lives and property safety of local people. Slope deformation monitoring and early identification of geological disasters in debris flow source areas are of great significance for disaster prevention and reduction. In this study, the time-series Synthetic Aperture Radar Interferometry (InSAR) technique was used to detect the deformation in the source area of the Baini river debris flow. The deformation rate in the middle part of the three-sided mountain is the largest, the average deformation rate is about 30 mm/year. The deformation rate of the lower and upper part of the mountain is slightly lower, but the deformation is creeping constantly, and obvious tensile cracks faced the river valley in the upper. The production and living areas of residents in 8 villages around the debris flow source area are constantly deformed, and there are different degrees of landslide risk. This study provides a scientific basis and reference for early identification, deformation analysis, disaster prevention and mitigation of geological disasters in the Xiaojiang Basin.

Analysis of the influence of electromagnetic interference of transmission lines on the data quality and positioning accuracy of Beidou deformation monitoring

In this paper, aiming at the application of geological disaster monitoring of transmission lines, by analyzing the data quality and positioning accuracy of Beidou original observation data, the influence of the electromagnetic environment of transmission lines on Beidou satellite monitoring data is obtained. According to the Beidou monitoring data of 500 kV transmission line for 23 days, the analysis results show that: in the case of strong electromagnetic interference/no electromagnetic interference, the difference of data integrity is less than 1%, the difference of multipath effect is less than 0.1 m, the difference of signal-to-noise ratio is less than 0.3 dB Hz, and the difference of cycle hop ratio is less than 150. The relative difference in positioning accuracy is less than 5%. In general, the electromagnetic environment of transmission lines has no significant impact on the data quality and positioning accuracy of Beidou deformation monitoring.

Scientific challenges in disaster risk reduction for the Sichuan–Tibet Railway

Traversing the Qinghai–Tibetan Plateau, the Sichuan–Tibet Railway is by far the most difficult railway project in the world. The Qinghai–Tibetan Plateau features the most active crustal dynamics on earth, the strongest coupling effects of endogenic and exogenic dynamics, and the environment most sensitive to global climate change. The project area is characterized by extremely cold climate, high elevation and relief, high seismic intensity, high geothermal activity, and high tectonic stress. Consequently, the threat of various disaster risks is ever-present at different stages of the entire life cycle of the Sichuan–Tibet Railway. There is urgent need to systematically study these problems at various levels from the fundamental science to the development of key technologies. This article investigates the different disaster risks recognized during the various stages of construction of the Sichuan–Tibet Railway project, and summarizes the scientific challenges and technical problems faced in relation to disaster risk prevention and control. This work also introduces the scientific deployment and relevant research progress of the Sichuan–Tibet Fund special project initiated by the National Natural Science Foundation of China. Here, we also aim to solve the major fundamental scientific challenges in terms of long-term risk prevention and control during the construction of the Sichuan–Tibet Railway, and lay a theoretical foundation to promote breakthroughs in the bottleneck of key technologies. The scientific challenges addressed in the study of disaster risk associated with the Sichuan–Tibet Railway include the following: The quantitative assessment of the activity of deep-large faults and strong earthquake prediction, the evolution of physical fields in areas of strong tectonic activity, the development mechanisms of tunnel hazards, the slope evolution processes under coupled endogenic and exogenic dynamics in alpine gorges, the impact of climate change on the formation and evolution of surface hazards, and the evolution of extreme wind fields in deep-cut canyons. The technical problems faced in disaster risk prevention and mitigation in relation to the Sichuan–Tibet Railway are as follows: Advanced identification, monitoring, and early warning of geological disasters in mountainous areas with steep and complex terrain; risk analysis, prevention, and control of railway engineering disasters based on their dynamic processes; tunnel engineering hazard monitoring, early warning, risk analysis, prevention, and control technologies; key technologies for emergency response; and the green and resilient railway system and lifecycle risk management. The Sichuan–Tibet Fund special project will include five key research topics: (1) the interior geological structure and dynamic evolution of the eastern plateau; (2) the hazard-inducing mechanisms of coupled internal and external forces in canyons and gullies within plateaus; (3) the cataclysm mechanics of deeply buried long-distance tunnel engineering; (4) risk identification and projection of major disasters affecting the railway; and (5) the integrated management of scientific innovations and super large-scale railway construction. Systematic research is expected to reveal the evolution of earth surface movements and coupled engineering-disturbance related disasters. It will also enable the formation of a comprehensive risk analysis method for major engineering disasters, and promote the development of green, safe, efficient, and resilient engineering disaster risk reduction technologies that will support the disaster risk management during the entire lifecycle of the Sichuan–Tibet Railway.

Novel closed-loop deployable mechanisms and integrated support trusses for planar antennas of synthetic aperture radar

Synthetic aperture radar (SAR) is indispensable electronic equipment in modern life, which has been widely used in the field of geological exploration, disaster monitoring, and environmental observation. With the increasing complexity of earth observation tasks, a higher receiving resolution of SAR is required, which needs the area of the radar antenna to be increased. However, there is a contradiction between the small launch space and the large working area. The deployable antenna mechanism is expected to meet the challenge. In this paper, a graphical type synthesis method is proposed to carry out the mechanism design of deployable mechanisms. According to the structural analysis and design requirements, the articulated form is adopted to carry sub-planes of planar antennas and provide one kinematic chain of the deployable mechanism. Then, different designed kinematic chains are synthesized to construct novel closed-loop deployable mechanisms. Mobility verification of a selected closed-loop deployable mechanism is carried out by screw theory to demonstrate the validity of type synthesis results. By sharing the provided kinematic chain and symmetrical design of two deployable mechanisms, deployable units with the driving unit are proposed as basic modules of support trusses for planar antennas. As a result, three novel deployable support trusses integrated by a series of deployable units and assembly mechanisms are proposed as the platforms for planar antennas. The deployable mechanisms and integrated support trusses proposed in this paper provide candidates for planar antennas of SAR.

Study on the Ground Fissure Development Law of Coal Mining Based on UAV Photogrammetry and the Particle Flow Theory

Ground fissures caused by underground coal seam mining easily result in secondary geological disasters and destroy the ecological environment, which seriously impacts the production and life of mining areas and residents. The traditional monitoring methods, such as manual measurement and satellite monitoring, have their disadvantages. Therefore, it is urgent to develop a large-scale monitoring technology for ground fissures and study its development law. In this article, we analyzed the distribution characteristics of ground fissures based on the low-altitude UAV remote sensing images and combined them with field investigation as validation. Moreover, we introduced the particle flow theory to study the development law and formation mechanism of ground fissures. This article takes the 8092 working face of a mine in Ordos City as the study area. The results showed that the accuracy rate of ground fissures based on the visual interpretation of UAV images was 95%. The ground fissures were mainly distributed near the stopping line and the groove of the working face. The plane forms of ground fissures were mainly two types: the linear type and arc type, and the location relationship can be divided into the parallel type and bifurcation type. The types of ground fissures were the tensile type and step type. Whether the upper and lower parts of the key strata were broken simultaneously is the root cause of tensile ground fissures and step ground fissures. The stability of the overlying strata had a significant influence on the change of abutment pressure above the goaf. The process of surface movement and deformation can be divided into three stages: tensile failure of the slope bottom, traction failure of the slope body, and sliding failure of the slope top. In addition, the zero point of the surface horizontal movement value and the maximum surface subsidence were not in the center of the goaf. Due to the horizontal slip of the downhill direction in the horizontal movement on the surface, the value of the downhill direction subsidence was zero. However, the value of the horizontal movement was not zero, and there was even a large horizontal movement. In conclusion, the research results can provide a useful reference for the rapid monitoring of large-scale geological disasters caused by underground coal seam mining and the application of the particle flow theory.

Monitoring Potential Geological Hazards with Different InSAR Algorithms: The Case of Western Sichuan

In recent years, the number of geological disasters in Sichuan Province has significantly increased due to the influence of earthquakes and extreme climate, as well as the disturbance to the geological environment by human activities. Thus, geological disaster monitoring is particularly important, which can provide some scientific basis for disaster prevention and reduction. In this paper, the interferometric synthetic aperture radar (InSAR) technology was introduced to monitor potential geological hazards, taking parts of Dujiangyan City, Wenchuan County, and Mao County in Sichuan Province, China as examples. Firstly, the data such as Sentinel-1A Terrain Observation with Progressive Scans (TOPS) Synthetic Aperture Radar (SAR) images and Precision Orbit Determination (POD) precise orbit ephemerides from 2018 to 2020, high-resolution optical satellite images and Digital Elevation Model (DEM) were collected. Secondly, the Differential InSAR (D-InSAR), Persistent Scatterer InSAR (PS-InSAR), Small Baseline Subset InSAR (SBAS-InSAR), Offset-Tracking, and Distributed Scatterer InSAR (DS-InSAR) algorithms were used to invert the surface deformation of the study area. Thirdly, according to the deformation results obtained by experiments, we used GF-1 and GF-2 optical images as a reference and combine the experimental results of InSAR algorithms to delineate the areas affected by geological disasters. A total of 49 geological disaster areas were obtained, mainly including landslides, collapses, and debris flow. Through field verification, the overall accuracy rate of InSAR deformation monitoring achieved 69.23%, and the accuracy rate of new potential hazards monitoring reached 63.64%. Among all InSAR methods, the DS-InSAR method outperformed and monitored the geological disaster areas well. Finally, the study area was divided into three elevation intervals and the applicability of different InSAR algorithms in different elevation intervals was discussed.

Application of Remote Sensing Technology in Geological Disaster Investigation and Monitoring

Application of Remote Sensing Technology in Geological Disaster Investigation and Monitoring

Unmanned Aerial Vehicle Surveying and Mapping Trajectory Scheduling and Autonomous Control for Landslide Monitoring

Real-time and efficient monitoring of geological disasters has received extensive attention in the application of UAV surveying and mapping control technology. The application of traditional landslide monitoring methods lacks the accuracy of control algorithms, which has become a hot issue currently facing. Based on the landslide surface subsidence monitoring method, this article designs the UAV trajectory scheduling subsidence monitoring software, which can monitor the UAV’s flight status and navigation information, and draw the flight trajectory in real time. At the same time, the model solves the problem of storage and management of landslide inspection results by the landslide inspection management system, and realizes the functions of entering and querying landslide information, viewing inspection results, landslide safety judgment, generating reports, and autonomous control. The simulation results show that the global accuracy reaches 0.975, and the algorithm recognition degree reaches 99.8%, which promotes the reliability of the landslide monitoring data for the identification of the surveying and mapping trajectory, and provides a decision-making basis for landslide treatment.

Monitoring, Prediction, and Evaluation of Mountain Geological Hazards Based on InSAR Technology

When traditional geological hazard survey methods are used for deformation monitoring in mountainous areas, it often shows the disadvantages of low applicability of monitoring methods and limited accuracy of detection results. In recent years, synthetic aperture radar interferometry (InSAR) technology has incomparable advantages in surface deformation monitoring, such as all-weather detection, wide detection range, high detection accuracy, and low detection cost. At the same time, InSAR technology can also provide data and technical support for the subsequent task of potential geological disaster point identification and geological disaster risk zoning in the study area. Alos-2 radar is selected; in this paper the satellite image is the research data, and the InSAR technology is used to complete the surface deformation detection. Then, based on the previous surface deformation monitoring results, the potential geological disaster points in the study area are extracted, and the distribution law and incubation conditions of the disaster points are analyzed and described. According to the field conditions of a certain area, the surface distribution, development causes, and inducing mechanism of the potential geological disaster points are explored; the results show that the development of geological disasters in the study area is affected by many factors such as landform, geological environment, climate, hydrology, and human activities. Based on this, 11 factors such as formation lithology, slope, and river are used as evaluation factors for mountain geological disaster monitoring, prediction, and evaluation analysis. Finally, the improved analytic hierarchy process information model is used to complete the monitoring, prediction, evaluation, and analysis of regional geological hazards in the study area. In this paper, the improved AHP-information method is used to classify the risk of mountain geological disasters in the study area. Finally, the evaluation results are verified, which proves that the improved AHP-information method is reliable, and its mountain geological disaster monitoring and prediction evaluation effect is better than the traditional AHP-information method.

Quality Evaluation of the 0.01° Multi-Source Fusion Precipitation Product and Its Application in Extreme Precipitation Event

High-resolution and high-quality precipitation data play an important role in Numerical Weather Prediction Model testing, mountain flood geological disaster monitoring, hydrological monitoring and prediction and have become an urgent need for the development of modern meteorological business. The 0.01° multi-source fusion precipitation product is the latest precipitation product developed by the National Meteorological Information Center to meet the above needs. Taking the hourly precipitation observation data of 2400 national automatic stations as the evaluation base, independent and non-independent test methods are used to evaluate the 0.01° multi-source fusion precipitation product in 2020. The product quality differences between the 0.01° precipitation product and the 0.05° precipitation product are compared, and their application in extreme precipitation events are analyzed. The results show that, in the independent test, the product quality of the 0.01° precipitation product and the 0.05° precipitation product are basically the same, which is better than that of each single input data source, and the product quality in winter and spring is slightly lower than that in summer, and both products have better quality in the east in China. The evaluation results of the 0.01° precipitation product in the non-independent test are far better than that of the 0.05° product. The root mean square error and the correlation coefficient of the 0.01° multi-source fusion precipitation product are 0.169 mm/h and 0.995, respectively. In the extreme precipitation case analysis, the 0.01° precipitation product, which is more consistent with the station observation values, effectively improves the problem that the extreme value of the 0.05° product is lower than that of station observation values and greatly improves the accuracy of the precipitation extreme value in the product. The 0.01° multi-source fusion precipitation product has better spatial continuity, a more detailed description of precipitation spatial distribution and a more accurate reflection of precipitation extreme values, which will better provide precipitation data support for refined meteorological services, major activity support, disaster prevention and reduction, etc.

Study on debris flow risk monitoring and Early Warning in Nujiang Prefecture, Yunnan Province, China

Debris flow is the mainly the geological disasters in Nujiang Prefecture, while precipitation is the trigger of it, how to implement debris flow forecast based on precipitation monitoring data or forecast data is a hot issue in current debris flow disaster research field. Because of the special geomorphology in Nujiang Prefecture, due to the influence of human activities, geological disasters occur frequently, severely affect the local economic development. As a demonstration area of geological disaster monitoring and early warning in Yunnan Province, to build a well-developed geological disaster warning system, it is very important to spread it to other parts of Yunnan province. Based on the analysis of the current situation of geological disasters in Nujiang Prefecture, adopt appropriate monitoring method and calculation method to select the primary sites for debris flow monitoring and early warning in the Nu River basin for research.

Application of Slope Radar (S-SAR) in Emergency Monitoring of the “11.03” Baige Landslide

On October 11 and November 3, 2018, the disaster chain of landslide-barrier lake occurred twice in Baige Village, Xizang Province. After the second sliding of the landslide, the danger of the landslide dam was eliminated by the manual excavation of the drain grooves. During this period, a ground-based interferometric synthetic aperture radar (GB-InSAR) called “S-SAR” was utilized for real-time monitoring and analyzing 48 selected target pixels on the residual deformation bodies of landslides (divided into K1, K2, and K3 deformation zones) for 8 days. Through the real-time deformation map of pixels in the monitoring area obtained by S-SAR, the ranges of five strong deformation regions were identified and delineated. Based on the apparent cumulative deformation-time curve of each target pixel, the overall deformation law of K1, K2, and K3 deformation zones could be monitored and analyzed in real time. Based on a curve graph of the deformation rate, acceleration, and time of each target pixel, the K1, K2, and K3 deformation zones were within a uniform deformation stage. Taking the target pixel point and the corresponding time in which the deformation rate and deformation acceleration had a large, abrupt jump at the same time as the position and time of the near-slip failure, the 11 positions and moments of the near-slip failure were counted. The results presented here may represent a workable reference for emergency monitoring and early warning of similar sudden geological disasters.

Landslide Monitoring and Early Warning System based on Edge Computing

With the advancement of modern sensing technology and network communication, the geological disaster monitoring and early warning technology is changing toward intelligence, continuity, and real-time monitoring. The most effective way to improve real-time monitoring and early warning is to conduct front-end analysis in the field of geological disasters. With the application of the Internet of Things technology in geological disasters, field data collection and field-level data strategies belong to the edge computing gateway for execution. According to the latest research trend of landslide on-site monitoring and early warning, edge computing gateways usually use thresholds for monitoring and early warning. On the basis of the empirical model of simple statistics or the theoretical model of landslide deformation early warning, key early warning indicators and weights are proposed to judge the stage of landslide evolution or disaster level. This study starts with a comprehensive analysis of the temporal and spatial evolution of the surface deformation area in the field of geological disaster monitoring. Then, an edge computing smart gateway is designed on the basis of the Linux operating system. The Long Range Radio field wireless sensor network is used to develop an automated monitoring system for slopes of displacement monitoring points, rainfall, and soil moisture content-inducing factors. Subsequently, the effective methods of obtaining multilevel topographic data of slopes are investigated using field information, such as the velocity and acceleration of surface displacement data. The slope multielement trigger monitoring model with multiple induced element coupling modes is explored to realize the front-end edge computing strategy method of slope monitoring and early warning. The analysis results can be sent to high-level data analysis servers, such as the software deployed on the Local Area Network and cloud servers of the relevant department for secondary use. This research overcomes the problems of regular collection of existing on-site monitoring instruments, loss of catastrophic information, and low effective data rate. Compared with traditional working modes, such as uploading the original monitoring data to a server for data extraction and analysis and then feedback to control the field equipment, using front-end edge computing is more efficient in realizing the first data processing utilization and adaptive monitoring processing. It can also provide more effective and reliable data for disaster monitoring and early warning. In conclusion, this research is of great significance in effectively capturing the laws of early evolution, improving real-time early warning capabilities, and promoting the industrialization of national geological disaster monitoring and early warning technology and equipment.

Experimental study on response law and failure process of slopes in fully weathered granites under precipitation infiltration

To investigate the response law and failure process of slopes in fully weathered granites under precipitation infiltration, a typical fully weathered granite slope is selected for sampling in South China. The physical simulation experimental study of rainfall-induced landslide is conducted, in which Weber criterion is used as the similarity criterion for precipitation. The research results reveal that under precipitation infiltration, the fully weathered granite slope responds quickly. Further, the water content increases sharply, and the matrix suction quickly dissipates. After dissipation, the matrix suction transforms into pore water pressure, which accelerates the deformation of the slope. The wet peak has a large infiltration depth in the slope, and the acceleration of the deep part is lower than that of the shallow part. Under the action of precipitation, the fully weathered granite model undergoes four stages of failure. Firstly, gullies and cracks appear; secondly, cracks propagate and link up; then, the soil on the slope surface swells and ruptures; and finally, the slope slides locally until the entire slope creeps, collapses, and transforms into a “soil flow”. It shows that the landslide will be triggered in fully weathered granite slope by precipitation when the precipitation intensity comes up to 155 mm/d, and the landslide occurs at an accumulated precipitation of 304 mm based on the analysis of precipitation similarity. Overall, the results can provide a reliable theoretical basis and abundant experimental data for the prevention, monitoring, and forecasting of geological disasters in granitic areas.

Application of Drilling Strain Analysis Technology in Mine Dynamic Geological Disaster Monitoring

This article applies the borehole strain observation technology to mine dynamic disaster monitoring for the first time, and uses the fractal box dimension to quantitatively analyse the time history change characteristics of borehole strain data and its correlation with rock bursts. The article uses the drilling multi-parameter test device to test in the mine, and judges the stress distribution by collecting the drilling parameter data obtained from the test hole of the working face of the test point. The study found that the application of borehole strain observation technology to mine dynamic disaster monitoring can directly and accurately record the micro-dynamic change process of rock mass in the area before and after the occurrence of rock burst. The fractal box dimension can quantify the complex changes and evaluation of strain data. Abnormal degree of water tide distortion.

FEASIBILITY VERIFICATION OF VIRTUAL REFERENCE STATION TECHNOLOGY IN GEOLOGICAL HAZARD MONITORING

Abstract. The surveying and mapping administrative competent departments in 31 provinces (autonomous regions and municipalities) have built provincial-level satellite navigation and positioning reference stations and data centers, and provided CORS services. This provides a good condition for exploring the application of geological hazard monitoring and early warning using Virtual Reference Station (VRS) service based on CORS. At present, the layout mode of "one point one reference station" is usually adopted, when GNSS is used for geological disaster monitoring and early warning. However, the high deployment cost of this plan limits its largescale promotion and application. Using the existing CORS service resources of natural resource system, this paper carried out the application experiment of virtual reference station in geological hazard monitoring application at Huanglongya geological hazard monitoring site in Shaanxi Province, and assessed the virtual reference station data quality, comparative analyzed the precision of static baseline processing results and GNSS real-time deformation monitoring results. The experimental results show that the overall quality of virtual reference station data is better than that of the monitoring station, and the accuracy of the static baseline calculation results is better than 1.0cm in the X direction, and better than 2.0cm in the Y direction and Z direction, which is similar to the static baseline calculation results formed by the physical reference station. The accuracy of the baseline results of real-time observation data calculation is better than 5mm in horizontal RMS and 15mm in vertical RMS. Therefore, it can be seen that the virtual reference station is feasible to be used as the reference station for geological disaster monitoring. In addition, the application experiment of network RTK real-time dynamic single epoch positioning mode is also carried out in geological hazard monitoring. The experimental results show that the RMS values of all three directions are ±3.7mm, ±9.2mm and ±5.0mm respectively, which meet the precision requirements of GNSS disaster monitoring. Therefore, it is also a feasible scheme for geological disaster monitoring and early warning.