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The solid backfilling mining method is one of the methods used to solve problems arising from strata and ground subsidence in underground mines. Through 2D physical analog modeling, 3D numerical simulation, and field measurement, the effects of the solid backfilling method were analyzed, providing a better insight into optimizing the configurations of a working face beneath a city for safety, environmental problems, and its use in production. In the physical modeling, MatchID software was employed to capture the movement characteristics of overlying strata and ground subsidence during mining and backfilling. Key parameters such as vertical displacement, subsidence characteristics, and rock mass stress variations were monitored and analyzed. In the numerical simulation, FLAC3D was used to simulate and analyze the effect of the backfill body on strata and ground subsidence above the backfill working face. For the field measurements, the Continuously Operating Reference Station (CORS) system was used to confirm the effective control of ground subsidence. With a filling ratio of 80%, the three methods are consistent and show a maximum subsidence value of 0.46 mm (physical simulation), 50.4 mm (numerical simulation), and 47 mm (experienced), significantly lower than the predicted subsidence, which is 281 mm. Therefore, this study demonstrates the reliability and scientific validity of both the physical analog modeling method and the field measurement method in measuring the efficiency of solid backfilling, providing valuable insights into strata and ground subsidence control in longwall coal mining. [ABSTRACT FROM AUTHOR]

Integrated geo- and environmental monitoring in mining represents a high-dimensional challenge (location, altitude/depth, time and sensors). This is challenging for experts but poses great problems for a multitude of participants and stakeholders in building up a complete process understanding. The Epe research cooperation aims to elucidate the ground movement at the Epe cavern storage facility with a public participation process. The research cooperation was founded by the city of Gronau, the citizens' initiative cavern field Epe, the company EFTAS, Münster, and the Research Center of Post-Mining at the Technische Hochschule Georg Agricola, Bochum. This research cooperation is the first in Germany to involve direct collaboration between science and the public. In the cavern field, which has been in operation since the 1970s, brine is extracted, and at the same time natural gas, crude oil and helium, as well as hydrogen in the future, are stored in the subsurface. The technical focus of this work was the development of a high-resolution spatiotemporal analysis of ground movements. The area is monitored annually by the mining company's mine surveyor. The complexity of the monitoring issue lies in the fact that the western part is a bog area and a former bog area. Furthermore, the soils in the eastern part are very humus-rich and show strong fluctuations in the groundwater and therefore complex hydraulic conditions. At the same time, there are few fixed scatterers or prominent points in the area that allow high-resolution spatiotemporal monitoring using simple radar interferometry methods. Therefore, the SBAS method (Small Baseline Subset), which is based on an aerial method, was used to analyze the radar interferometric datasets. Using an SBAS analysis, it was possible to evaluate a time series of 760 scenes over the period from 2015 to 2023. The results were integrated with the mine survey maps on the ground movement and other open geodata on the surface, the soil layers and the overburden. The results show complex forms of ground movement. The main influence is that of mining. Nevertheless, the influence of organic soils with drying out due to drought years and uplift in wet years is great. Thus, in dry years, ground subsidence accelerates, and in wet years, ground subsidence not only slows down but in some cases also causes uplift. This complexity of ground movements and the necessary understanding of the processes involved has been communicated to the interested public at several public information events as part of the research cooperation. In this way, an understanding of the mining process was built up, and transparency was created in the subsurface use, also as a part of the energy transition. In technical terms, the research cooperation also provides a workflow for developing the annual mine survey maps into an integrated geo- and environmental monitoring system with the development of a transparent participatory geomonitoring process to provide resilience management to a mining location. [ABSTRACT FROM AUTHOR]

Direct and indirect effects after mine operations cease operating must ideally be subjected to perpetual monitoring routines in order to detect possible risks or avoid adverse effects on the surrounding ecosystems at an early stage. In this contribution, mining subsidence lakes created inside the nature reserve Kirchheller Heide and Hilsfeld Forest are subjected to analysis for a long-term monitoring scheme. For this purpose, we employ high-resolution unmanned aerial system (UAS)-based multispectral and thermal mapping tools to provide a fast, non-invasive and multitemporal environmental monitoring method. Specifically, we propose to monitor vegetation evolution through multispectral analysis, biotypes identification using machine learning algorithms, and water surface extent detection, together with their thermal behavior. The aim of this contribution is to present the proposed workflow and first results to establish a baseline for future analyses and subsequent surveys for long-term multi-temporal monitoring. [ABSTRACT FROM AUTHOR]

Integrated geo- and environmental monitoring in mining represents a high-dimensional challenge (location, altitude/depth, time and sensors). This is challenging for experts but poses great problems for a multitude of participants and stakeholders in building up a complete process understanding. The Epe research cooperation aims to elucidate the ground movement at the Epe cavern storage facility with a public participation process. The research cooperation was founded by the city of Gronau, the citizens’ initiative cavern field Epe, the company EFTAS, Münster, and the Research Center of Post-Mining at the Technische Hochschule Georg Agricola, Bochum. This research cooperation is the first in Germany to involve direct collaboration between science and the public. In the cavern field, which has been in operation since the 1970s, brine is extracted, and at the same time natural gas, crude oil and helium, as well as hydrogen in the future, are stored in the subsurface. The technical focus of this work was the development of a high-resolution spatiotemporal analysis of ground movements. The area is monitored annually by the mining company’s mine surveyor. The complexity of the monitoring issue lies in the fact that the western part is a bog area and a former bog area. Furthermore, the soils in the eastern part are very humus-rich and show strong fluctuations in the groundwater and therefore complex hydraulic conditions. At the same time, there are few fixed scatterers or prominent points in the area that allow high-resolution spatiotemporal monitoring using simple radar interferometry methods. Therefore, the SBAS method (Small Baseline Subset), which is based on an aerial method, was used to analyze the radar interferometric datasets. Using an SBAS analysis, it was possible to evaluate a time series of 760 scenes over the period from 2015 to 2023. The results were integrated with the mine survey maps on the ground movement and other open geodata on the surface, the soil layers and the overburden. The results show complex forms of ground movement. The main influence is that of mining. Nevertheless, the influence of organic soils with drying out due to drought years and uplift in wet years is great. Thus, in dry years, ground subsidence accelerates, and in wet years, ground subsidence not only slows down but in some cases also causes uplift. This complexity of ground movements and the necessary understanding of the processes involved has been communicated to the interested public at several public information events as part of the research cooperation. In this way, an understanding of the mining process was built up, and transparency was created in the subsurface use, also as a part of the energy transition. In technical terms, the research cooperation also provides a workflow for developing the annual mine survey maps into an integrated geo- and environmental monitoring system with the development of a transparent participatory geomonitoring process to provide resilience management to a mining location.

Direct and indirect effects after mine operations cease operating must ideally be subjected to perpetual monitoring routines in order to detect possible risks or avoid adverse effects on the surrounding ecosystems at an early stage. In this contribution, mining subsidence lakes created inside the nature reserve Kirchheller Heide and Hilsfeld Forest are subjected to analysis for a long-term monitoring scheme. For this purpose, we employ high-resolution unmanned aerial system (UAS)-based multispectral and thermal mapping tools to provide a fast, non-invasive and multitemporal environmental monitoring method. Specifically, we propose to monitor vegetation evolution through multispectral analysis, biotypes identification using machine learning algorithms, and water surface extent detection, together with their thermal behavior. The aim of this contribution is to present the proposed workflow and first results to establish a baseline for future analyses and subsequent surveys for long-term multi-temporal monitoring.

The solid backfilling mining method is one of the methods used to solve problems arising from strata and ground subsidence in underground mines. Through 2D physical analog modeling, 3D numerical simulation, and field measurement, the effects of the solid backfilling method were analyzed, providing a better insight into optimizing the configurations of a working face beneath a city for safety, environmental problems, and its use in production. In the physical modeling, MatchID software was employed to capture the movement characteristics of overlying strata and ground subsidence during mining and backfilling. Key parameters such as vertical displacement, subsidence characteristics, and rock mass stress variations were monitored and analyzed. In the numerical simulation, FLAC3D was used to simulate and analyze the effect of the backfill body on strata and ground subsidence above the backfill working face. For the field measurements, the Continuously Operating Reference Station (CORS) system was used to confirm the effective control of ground subsidence. With a filling ratio of 80%, the three methods are consistent and show a maximum subsidence value of 0.46 mm (physical simulation), 50.4 mm (numerical simulation), and 47 mm (experienced), significantly lower than the predicted subsidence, which is 281 mm. Therefore, this study demonstrates the reliability and scientific validity of both the physical analog modeling method and the field measurement method in measuring the efficiency of solid backfilling, providing valuable insights into strata and ground subsidence control in longwall coal mining.

Geomechanical monitoring of the rock mass state is an actively developing branch of geomechanics, in which it is impossible to distinguish a single methodology and approaches for solving problems, collecting and analyzing data when developing seismic monitoring systems. During mining operations, all natural factors are subject to changes. During the mining of a rock mass, changes in the state of structural inhomogeneities are most clearly manifested: the existing natural structural inhomogeneities are revealed; there are movements in discontinuous disturbances (faults); new man-made disturbances (cracks) are formed, which are accompanied by changes in the natural stress state of various blocks of the rock mass. The developed method for evaluating the results of monitoring geomechanical processes in the rock mass on the example of the United Kirovsk mine of the CF AO Apatit allowed to solve one of the main tasks of the geomonitoring system – to predict the location of zones of possible occurrence of dangerous manifestations of rock pressure.

The concept of geomonitoring and its role in developing the mining industry as a case study of the development of copper and zinc deposits in central Kazakhstan ("East Saryoba" mine) has been considered. As a crucial element of the geomonitoring concept, the control of the open-pit mine's slope stability has been examined. Geomonitoring is being treated as a combination of geodetic monitoring data and geomechanical properties of the surrounding rocks to analyze the possible slopes' collapses. The refined approach of geomonitoring has been developed to provide appropriate reliability and accuracy. The technology is based on complex knowledge about the geological structure of the object of monitoring and applying state-of-the-art geodetic methods. Research on the geomechanical properties of the open-pit mine has been carried out. The results of these studies have been used to determine the collapse zones of the slopes of the open-pit mine. The limit values for the slopes' collapse zone and inclination angle for the prospective excavation regions in the open-pit mine have been calculated using the equilibrium state equation. Those values, namely, the size of the collapse zone and the slope's inclination angle, were used for the geodetic target setup. As a case study, the displacements of these targets were measured using robotic total stations placed on the control points over the geodetic network. For the installation of both geodetic equipment during the geomonitoring design and accomplishment, the authors developed the permanent measuring station construction, which provides fast and accurate centering. The first results showed that the problem of the geomonitoring design could be solved based on geomechanical rock properties accounting and their combination with the results of geodetic measurements. [ABSTRACT FROM AUTHOR]

TRIM4Post-Mining is a H2020/RFCS-funded project that brings together a consortium of European experts from industry and academia to develop an integrated information modelling system. This is designed to support decision making and planning during the transition from coal exploitation to a revitalized post-mining landscape, enabling infrastructure development for agricultural and industrial utilization, and contributing to the recovery of energy and materials from coal mining dumps. The smart system will be founded upon a high-resolution spatiotemporal database, utilizing state-of-the-art multi-scale and multi-sensor monitoring technologies that characterize dynamic processes in coal waste dumps related to timely, dependent deformation and geochemical processes. It will integrate efficient methods for operational and post-mining monitoring, comprehensive spatiotemporal data analytics, feature extraction, and predictive modelling; this will allow for the identification of potential contamination areas and the forecasting of geotechnical risks and ground conditions. For the interactive exploration of alternative land-use planning scenarios—in terms of residual risks, technical feasibility, environmental and social impact, and affordability—up-to-date data and models will be embedded in an interactive planning system based on Virtual Reality and Augmented Reality technology, forming a TRIM—a Transition Information Modelling System. This contribution presents the conceptual approach and main constituents, and describes the state-of-the-art and detailed anticipated methodological approach for each of the constituents. This is supported by the presentation of the first results and a discussion of future work. An anticipated second contribution will focus on the main findings, technology readiness and a discussion of future work.

Mining of minerals impacts all components of the ecosystem and the post-mining environment should be continuously monitored to control the quality and efficiency of reclamation procedures. In the past post-mining areas often did not undergo the full process of reclamation and were left unmonitored. This study was aimed at analysis of surface (gully) erosion in an abandoned lignite post-mining area located in the present cross border German-Polish Geopark Muskau Arch. For this purpose, low-cost unmanned aerial vehicle (UAV) photogrammetry to acquire data describing the surface condition of partly rehabilitated dump sites and subsequently a digital elevation model (DEM) of difference (DoD) approach to analyse quantitatively elevation change were applied. The results based on processing of data from four UAV missions carried out between Spring 2020 and Autumn 2021 (18 months) allowed to determine the elevation models with high accuracy (±0.02 – ±0.04 m) and develop differential elevation models for the estimation of material movement and surface change in three selected gullies. All of the study sites were subjected to surface erosion probably due to the effect of rainfall that caused natural landscaping of the area. The greatest observed elevation changes connected with loss of material in research crosssections reached 0.9 m. The UAV based data calculation of the DEM of difference has proved a time efficient and accurate method for analysis of elevation change in post-mining areas subjected to surface erosion. For the best results it is recommended to plan the UAV flight missions when the sun is at its highest or in cloudy weather to minimise the effect of sunshading on the quality of the generated DEMs. A further study to correlate material movement with precipitation records is planned. [ABSTRACT FROM AUTHOR]

For the Research Centre of Post-Mining (FZN) at the Technische Hochschule Georg Agricola University (THGA) in Bochum, geomonitoring is a multi-level approach to environmental monitoring with a focus on post-mining activities. In situ, a precise understanding of natural processes, e.g. the condition of groundwater, water bodies, soil or vegetation, is developed – usually through mapping, laboratory analyses and installed sensors. The goal is to later be able to derive an areawide statement on these processes through the analysis of satellite data. In order to be able to transfer the process understanding gained to the satellite data, an unmanned aerial vehicle is used. This article highlights an essential aspect of the in situ component. The denser the coverage with sensors, the more reliably an area-wide statement about drones and satellites can succeed. This is why low-cost temperature and soil moisture sensors and loggers are also used in the FZN research projects. In the “Climate Change – Management and Monitoring (C2M2)” project, funded by the Emschergenossenschaft-Lippeverband (EGLV), such sensors could be evaluated in several tests. The article presents initial results aimed at mapping an annual cycle of soil moisture with such inexpensive sensors. As a result, no physically correct measurements can be achieved with these sensors, but they are able to show patterns in processes and, for example, map such annual cycles. With the appropriate interpretation, they can thus deliver a contribution to understand processes. [ABSTRACT FROM AUTHOR]

The life cycle of the provision of geo-resources from the legal permission for exploration, through the process of extraction, to the decommissioning of sites is a long process in time and has a local, regional as well as supra-regional impact. The results of several projects show the necessity of integrating the methods of environmental and geomonitoring for spatiotemporal monitoring. Here, the fusion and upscaling of multiple geospatial data layers plays an important role. The project examples show the multisensor fusion of satellite remote sensing with copter flights and in-situ sensors. Only by considering the entire provisioning process of georesources, the necessary knowledge from the final phase can be used for future provisioning processes. In addition, the project results show the importance of considering the effects of changes in local climatological conditions (including precipitation). The projects illustrate that in addition to documenting the actual spatiotemporal changes, geospatial and environmental monitoring offers the possibility of project controls. This necessitates an expansion of the definition of geo- and environmental monitoring, but also the implementation of measures. In summary, however, it is also apparent that only through the fusion of several approaches the development of a geoscientific understanding of processes is achieved. [ABSTRACT FROM AUTHOR]

Formulation of the problem. The paper is the beginning of scientific papers series of authors on an actual environmental topic – multidimensional system geomonitoring of groundwater in water intakes areas. The purpose of article is a substantiation of application possibility of the method of objects trajectory modeling in the normalized phase space, which has been developed at V. N. Karazin Kharkiv National University for socio-geographical monitoring tasks, for hydrogeological objects geomonitoring. Materials and methods. The research is based on the method of objects trajectory modeling in the normalized phase space. To achieve the purpose of this study, geomonitoring data of five water intakes in Poltava city, which operate Cenomanian-Lower Cretaceous aquifer, has been used. Changes in the average chemical composition of groundwater for each water intake have been analyzed according to 12 indicators: pH, hardness, dry residue, ammonium, fluorine, chlorine, sulfates, bicarbonates, calcium, magnesium, sodium+potassium, ferrous iron. The initial data have been collected from 1981 to 2008 according to an irregular pattern in time (39 points in time). Research results. The following indicators of systemic development of hydrogeological system have been calculated for each water intake: a) for each period of time – the path length traveled by the water intake hydrogeological system, which characterizes the intensity of changes in the groundwater chemical composition; b) for each control time – the projection of current trajectory point on the optimal trajectory (main diagonal), the deviation of point from the optimal trajectory, the progress coefficient (the ratio of point projection to the length of main diagonal). The main trends in the systemic development of hydrogeological system for all studied water intakes have been identified: - the intensity of changes in the groundwater chemical composition at water intakes Nos. 1-5 decreases over time, which can be explained by the reduction of water withdrawal and hydrodynamic factors associated with the formation of depression funnel, in particular the spreading of quasi-stationary filtration regime; - according to the absolute values of changes intensity in the groundwater chemical composition, the water intake No. 3 is highlighted, the value of which is significantly less than the values of other water intakes; - groundwater at the water intake No. 1 has the greatest variability in the changes intensity of chemical composition over time both in amplitude and in absolute values; - there is a very noticeable synchronization of movement intensity graphs of water intakes hydrogeological systems in the normalized phase space and the average intensity of changes in the groundwater chemical composition, but a detailed analysis reveals some deviations from this pattern, which may be due to abrupt changes in operation mode of water intakes.

In April 2001 a rock fall at the Lärchberg-Galgenwald with boulders of several cubic meters in size did occur, which reached until the 50 to 70 m wide apron of the Federal Highway B96. This event triggered the installation of a fivemeter-high protective dam and the start of a geodetic monitoring program based on rope extensometer measurements and a geodetic survey. This study area is used to test further methods of image processing-based monitoring and to show the advantages and disadvantages with the focus on the main area of the landslide. The two technologies used are structure-from-motion (SfM) and terrestrial laser scanning technology. Both systems work through contactless data acquisition by active and passive recording processes. A data set in the form of a point cloud and a digital surface model with a grid size of 10 cm, which are checked for accuracy on the basis of measured control points, was created across all methods. As a further approach, the fusion of the point clouds from the flight using an unmanned aerial vehicle (UAV) and the laser scan point clouds was carried out.

In April 2001 a rock fall at the Lärchberg-Galgenwald with boulders of several cubic meters in size did occur, which reached until the 50 to 70 m wide apron of the Federal Highway B96. This event triggered the installation of a fivemeter-high protective dam and the start of a geodetic monitoring program based on rope extensometer measurements and a geodetic survey. This study area is used to test further methods of image processing-based monitoring and to show the advantages and disadvantages with the focus on the main area of the landslide. The two technologies used are structure-from-motion (SfM) and terrestrial laser scanning technology. Both systems work through contactless data acquisition by active and passive recording processes. A data set in the form of a point cloud and a digital surface model with a grid size of 10 cm, which are checked for accuracy on the basis of measured control points, was created across all methods. As a further approach, the fusion of the point clouds from the flight using an unmanned aerial vehicle (UAV) and the laser scan point clouds was carried out. [ABSTRACT FROM AUTHOR]

TRIM4Post-Mining is a H2020/RFCS-funded project that brings together a consortium of European experts from industry and academia to develop an integrated information modelling system. This is designed to support decision making and planning during the transition from coal exploitation to a revitalized post-mining landscape, enabling infrastructure development for agricultural and industrial utilization, and contributing to the recovery of energy and materials from coal mining dumps. The smart system will be founded upon a high-resolution spatiotemporal database, utilizing state-of-the-art multi-scale and multi-sensor monitoring technologies that characterize dynamic processes in coal waste dumps related to timely, dependent deformation and geochemical processes. It will integrate efficient methods for operational and post-mining monitoring, comprehensive spatiotemporal data analytics, feature extraction, and predictive modelling; this will allow for the identification of potential contamination areas and the forecasting of geotechnical risks and ground conditions. For the interactive exploration of alternative land-use planning scenarios—in terms of residual risks, technical feasibility, environmental and social impact, and affordability—up-to-date data and models will be embedded in an interactive planning system based on Virtual Reality and Augmented Reality technology, forming a TRIM—a Transition Information Modelling System. This contribution presents the conceptual approach and main constituents, and describes the state-of-the-art and detailed anticipated methodological approach for each of the constituents. This is supported by the presentation of the first results and a discussion of future work. An anticipated second contribution will focus on the main findings, technology readiness and a discussion of future work. [ABSTRACT FROM AUTHOR]

The article is devoted to comparison of methods of calculating the approximate elevations of nodal points when adjusting leveling networks by strict and non-strict methods. Ensuring geomechanical monitoring of the mutual influence of constructed and operated objects is important in the intensive development of underground space of megacities, the construction of unique objects and structures. In the course of the research, mathematical models of level networks were developed and presented in the form of a closed loop and a set of open polygons. Analysis of modeling allows to determine the feasibility of applying the knot method by Professor V.V. Popov instead of the parametric method of adjustment. It is established that the quality of the results of strict equalization depends entirely on the quality of measurements, since deviations from the true values do not exceed the measurement error. The research has shown that it is possible to simplify the processing of monitoring data and evaluation of various configuration options for leveling networks, using algorithms for calculating approximate marks of nodal points. This makes it easier to process monitoring results and evaluate various network configuration options while ensuring the required level of measurement accuracy.

Copyright of Visnyk of Karazin Kharkiv National University. Series "Geology-Geography-Ecology" is the property of V.N. Karazin Kharkiv National University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Scientific Bulletin of National Mining University is the property of National Mining University, State Higher Educational Institution and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The advantages of terrestrial laser scanning (TLS) for geodetic monitoring of man-made and natural objects are not yet fully exploited. Herein we address one of the open challenges by proposing feature-based methods for identification of corresponding points in point clouds of two or more epochs. We propose a learned compact feature descriptor tailored for point clouds of natural outdoor scenes obtained using TLS. We evaluate our method both on a benchmark data set and on a specially acquired outdoor dataset resembling a simplified monitoring scenario where we successfully estimate 3D displacement vectors of a rock that has been displaced between the scans. We show that the proposed descriptor has the capacity to generalize to unseen data and achieves state-of-the-art performance while being time efficient at the matching step due the low dimension. [ABSTRACT FROM AUTHOR]

A bibliometric study of publications on functional nanomaterials in Russia and worldwide is presented. The Scopus - abstracts database with analytical facilities (Elsevier, Netherlands) is used for defining the publication activity of Russian organizations. The ranking list of organizations with high publication activities is outlined. The departmental and regional productivity in the field of functional nanomaterials is explored. [ABSTRACT FROM AUTHOR]