Rock Salt Mine Research Articles

An assessment of ground subsidence from rock salt mining in Maceió (Northeast Brazil) from 2019 to 2023 using remotely sensed data

This study investigates ground subsidence in Maceió, the capital of Alagoas, Brazil, utilizing Sentinel-1 Synthetic Aperture Radar (SAR) data from November 2019 to December 2023. Ground subsidence poses significant risks to urban infrastructure and requires comprehensive monitoring and mitigation strategies. We employed the Interferometric Wide Swath (IW) mode of Sentinel-1A, acquiring high-resolution data in descending orbit with VV polarization. Through interferometric processing, including co-registration, phase unwrapping, and coherence estimation, we produced detailed subsidence maps for key neighborhoods such as Bebedouro, Farol, Mutange, Pinheiro, and Bom Parto. Our results reveal that subsidence in Maceió is highly variable across different neighborhoods, with cumulative subsidence reaching up to 3.83 meters in the most affected areas. The Bebedouro neighborhood, for instance, experienced subsidence up to 0.33 meters over an area of 41.85 hectares, while Farol saw significant ground movement impacting 59.49 hectares. The analysis indicates that high-density urban areas are particularly susceptible to subsidence, correlating with increased structural damage and flood vulnerability. The study underscores the importance of integrating geotechnical, urban planning, and environmental management strategies to address subsidence. We recommend the implementation of adaptive urban planning measures and enhanced monitoring techniques using satellite data to mitigate the impact of subsidence on infrastructure and communities. These findings provide a critical foundation for developing resilient urban environments in coastal cities prone to geological and anthropogenic subsidence.

Prehistoric Rock Salt Mining and the mines of St. Thomas and Camp Verde in the Southwest of the USA

Prehistoric rock salt mining and its archaeological investigations allows many fascinating insights into prehistoric communities, not only on techniques of exploitation but also on supply and nourishment, the miner’s health statues, the whole world of organic items of a broad material culture and also the social status and circumstances of mining. Salt mummies, as other organics best preserved, range onto the most outstanding findings. Worldwide 7 ancient rock salt mines are known, some nearby the surface (Duzdaği-Chehrābād type), some up to several hundred meter underground (Hallein-Hallstatt type). The rock salt mines of the Southwest of the USA belong to the first type. Research done in the 1920ies enable an overview about our archaeological knowledge.

Substantiation of rib pillar sizes for rock salt mining in vertical cylindrical stopes

Substantiation of rib pillar sizes for rock salt mining in vertical cylindrical stopes

Substantiation of rib pillar sizes for rock salt mining in vertical cylindrical stopes arranged at the nodes of regular triangular pattern

Substantiation of rib pillar sizes for rock salt mining in vertical cylindrical stopes arranged at the nodes of regular triangular pattern

Using Group Decision-Making to assess the negative environmental, social and economic impacts of unstable rock salt mines in Maceio, Brazil

The disaster caused by the instability of rock salt mines in Maceió, Brazil, is the largest ongoing worldwide socio-environmental disaster in urban areas and has already affected approximately 60,000 families directly who needed to be relocated. To assess the negative impacts caused by this disaster, a Group Decision-Making (GDM) model was developed based on qualitative (Thematic Content Analysis) and quantitative (Nominal Group Technique) analysis. A comparative evaluation of the opinion of three groups of stakeholders was performed: two considered as experts, i.e., academic professors and local public agents, and a group of citizens directly affected by the disaster. As a result, the residents considered the relevance of the impacts in the three dimensions analyzed to be similar, while the experts gave greater importance to the social and economic dimensions than the environmental one. This study potentially contributes to society by guiding public policymakers in the decision-making process on mitigation and preventive actions, and academics interested in the governance of disasters caused by mining industries.

Numerical implementation and application of an internal state variable model to analyze the time-dependent behavior of mining excavations in rock salt

The geomechanical behavior of rock salt has been investigated extensively over the years. Experimental studies have identified distinctive features associated with nonlinear inelastic response that shows strong time and loading history dependencies. In this paper, a relatively simple constitutive model is presented and implemented into the numerical code FLAC, and then applied to analyze the time-dependent behavior of excavations in salt mines. The unified creep-plasticity model includes an internal state variable (ISV) with an evolution law that induces progressive strain hardening (SH) until a steady state is reached. Numerical analyses are performed with the proposed ISV–SH model to evaluate material parameters, based on creep test results on natural rock salt, and to simulate the response of a circular opening and of rectangular mining excavations created in sequence. The results are analysed and compared with those obtained with the well-known Norton power law equation, commonly used in salt mine engineering. The time-dependent calculation results illustrate key aspects of rock salt behavior and highlight the major influence of transient inelastic behavior and stress redistribution on the response of underground openings. The proposed modelling approach constitutes an advantageous alternative to analyses based on stationary creep laws, often used in rock salt mining operations.

Stability evaluation of room-and-pillar rock salt mines by using a flat jack technique - A case study

Room-and-pillar mining is commonly employed for the extraction of rock salt in underground mines. Pillar stress is a major concern in these mines as it is directly related to stability and mineral recovery. In this study a flat jack method was used to measure pillar stresses in three underground rock salt mines in Pakistan. The field work included determination of in-situ stress, in-situ elastic modulus, recording of field variables (pillar length and width, height and width of opening, opening width to height ratio, extraction ratio, and overburden height) and collection of salt block samples. The geomechanical properties of rock salt (uniaxial compressive strength, Young's modulus, Brazilian tensile strength, and density) were also determined to estimate overburden stress, pillar strength, and factor of safety (both estimated and actual). It was found that the measured pillar stresses are proportional to the overburden stress values, with their magnitude ranging from 6.05 MPa to 11.97 Mpa, and the pillars were found to be stable. Regression analysis was performed to develop statistical models for in-situ stress and in-situ elastic modulus. Finally a quick guideline chart was developed to determine the suitable length of pillar for a given span and required level of safety. Keywords: flat jack, room-and-pillar mining, in-situ stress, factor of safety, regression analysis.

Surface Deformation Monitoring and Risk Mapping in the Surroundings of the Solotvyno Salt Mine (Ukraine) between 1992 and 2021

The historical Ukrainian rock-salt mining town of Solotvyno and its environmentally related problems are well-known. A complex monitoring system is needed to evaluate the current situation in order to revitalize the investigated area. In addition to other risks, surface deformation due to undermining is one of the major risks endangering building infrastructure in the inhabited area of the town. These processes are well-known in the area, and damages caused by the surface movement are often recognized. Measurement of the process’s intensity and identification of the impacted area are crucial for any revitalization work. Information on these processes is the most important element of the hazard management and spatial-developmental planning of the town. This study aimed to characterize the long-term surface deformation processes and to identify the spatial and temporal trends and changes of these processes to assist spatial planning. The first step was to understand the surface deformation history from 1992. An InSAR-based assessment of the surface displacement of the undermined Solotvyno area was performed using data from three satellites, namely the ERS, Envisat, and the Sentinel-1, covering the time period between 1992 and 2021. The derived quantitative analysis indicated an intensive surface displacement and subsidence over the mining area. However, these displacements have not been even in the last 30 years of the investigation. The identification of the stabilized areas and recently started movements indicated the dislocation of the processes, which requires adequate actions for geohazard management and strategic planning. The demonstrated technology (InSAR) has the potential to set up an appropriate alarm system and provides an automated mechanism for continuous risk detection. A complex systems development is able to significantly reduce the geohazards over the unstable built-up zones.

Калийная промышленность России: проблемы рационального и безопасного недропользования

The Russian Federation controls almost a quarter of potash fertilizer world market. Natural potassium salts serve as the main source for the fertilizer production. Mineral and raw materials base considers nine potash deposits to be on the state balance. However, potash mining in production quantities is currently executed only at the Perm region Verchnekamskoe deposit by four mines of the Uralkali Company and by the Usolskiy mine of EuroChem. During 2020 almost 52 million t were mined, which allowed to produce more than 14 million t of potash fertilizer. The main feature of salt deposit development is the necessity to protect the mines from fresh and brackish waters breakthrough. Experience of developing potash deposit throughout the world helped to formulate basic principles of mining operations. Protection of mine openings from underground and surface waters, that are corrosive to the rock salts, is secured by formation of a waterproof rock stratum, referred to as the waterproof pillar in mining practice, between the top of the upper mined layer and the bottom of the lowest aquifer. Usually, it is achieved through application of the room-and-pillar mining system that has to maintain the integrity of the waterproof pillar during the mine life until its liquidation and completion of the undermined rock mass deformation process. Despite the applied security measures, a significant number of mines were lost as a result of hazardous flooding. Three large-scale accidents took place at the Verchnekamskoe deposit. Mining and geological conditions that accompanied those hazardous situations are examined, and analysis of probable causes of water breakthrough into mine openings is carried out. Based on summarizing the experience of Verchnekamskoe potash deposit development it is demonstrated that the main factor that determines the efficiency of rock salt mining is provision of mining security and protection of mines from flooding. At the same time the approach to minimization of anthropogenic hazards should be based on applying justified engineering regulations at the mine planning stage and on the up-to-date information-based scientific support of the mining process, based on permanently functioning system of complex monitoring of the rock mass state.

Underground in-situ investigation of spatial and temporal changes of rock salt integrity in the marginal area of a natural CO2-rich cavernous structure

In this paper, we present an in-situ study of the marginal area of a CO2- and brine-rich cavernous structure in an underground rock salt mine. To reveal sources and dynamics of fluid movement, the temporal and spatial distribution of fluids in the potentially weakened cavern rim in salt were investigated. Seismic imaging, followed by long-term gas monitoring were applied along a transect from the cavernous structure to the undisturbed rock formation. The underground seismic survey comprised travel time tomography and pre-stack depth migration and showed, in agreement with the results of gas monitoring, disturbed areas without correlation to the cavernous structure. During two years, the monthly gas inflow into isolated borehole sections revealed insights into short term changes of gas migration pattern in rock salt. The measurements showed gas influx of up to 4 kPa/day and CO2 concentrations of up to 1.2%, especially during the beginning of the campaign. The gas migration is coupled to discrete fracturing and was observed to be spatially and temporary confined. Overall, no correlation between gas occurrences and their distance to the cavern exists, suggesting no wide-ranging fluid-rock interaction in the rim of the investigated natural cavernous structure in rock salt. The occurrence of gas is coupled to spatially and temporary limited fracturing which evidently healed and regained rock salt typical tightness.

Post Mining Application: Tuzluca Rock Salt Mine Therapy Center for Health Tourism

The rapid development of technology coupled with the increases in population led to requirement of raw materials. For that reason, the largest quantity of production is needed but the large production causes significant social, economic and ecological consequences regarding a sustainable mining activity. Preserving the relevant balances reveals the necessity of developing sustainable projects after mining. Thus, development or sustainable development should be defined not only as increasing the welfare level, but also as protecting human rights, political rights and ecological balance, and leaving a liveable world to future generations. Herewith present study, Tuzluca rock salt mine was been assessed. Due to being located on the Silk Road, Tuzluca (Igdir, Turkey) rock salt mine with its rich reserves and tenors has been of great economic importance since ancient times. Within the areas of this salt mine, the production is still being carried out but the relevant and safe areas are under project for salt therapy purposes. Due to the unique properties of the salt mine and underground air, and its therapeutic ability potential, these areas have been assessed for health tourism, viz. Speleotherapy and Halotherapy center. These treatments are known to be very beneficial for respiratory tract, ear, nose, throat and skin diseases within the framework of complementary medicine applications. However, we should herein note that mining activities carried out might bring significant consequences regarding the social and ecological structures of the region. With the ongoing increase in mining activities, it has enabled the necessary investments, employment, education, trade and infrastructure for the residential area to develop over time. Along with the present project, we have aimed at developing and providing a sustainable prosperity and a safe future after salt mining activities, also aiming at making significant contributions to the region.

Stope stability assessment by the Mathews–Potvin method: a case-study of open stoping in salt rock mass under conditions of secondary stress field

Predicting the stability of open stopes is a challenging task for underground mine engineers. The introductory part of this paper presents main issues related to stability and safety of soil and rock mass in course of large earthworks and underground works. On the basis of former studies, this paper reviews the research findings on stope stability by the methods of Mathews and Potvin in the stoping design for rock salt mines operating at depths greater than 1 km under conditions of secondary stress fields, as well as the rock mass quality assessment by Barton’s method. The conservative stope design has been performed for a few scenarios of design parameters. In conclusions, it is underlined by the stability graph at the given parameters, that in the first case-study scenario, HR is 4.5 m and the Mathews–Potvin stability number is 68 m. It is concluded that the stopes will be stable and preserve their shapes. On the basis of presented case study (stope stability assessment in the test halite–polyhalite–polymineral salt deposit was carried out for a few scenarios at maximal effective stresses and under conditions of jointing), the authors provide the general provisions on salt rock mass assessment at great depths.

Geomechanical justification of room-and-pillar dimensions for rock salt and polymineral salt mining

The key target of room-and-pillar planning for mining rock salt, polymineral salt and polyhalite at the minimized loss of minerals in pillars is optimization of the dimensions of rooms and rib pillars. The authors compare some variants of mining with rooms and rib pillars, as well as with honeycomb mine structure. The theoretical and experimental studies prove efficiency of room-and-pillar dimension optimization by combination of analytical estimation with numerical analysis and physical modeling of the stress–strain behavior of underground structures (honeycomb mine structures). It is found that the honeycomb mine structures feature higher resistability of structural components to external loads. The research into secondary stress field generation and influence on structural elements of the roomand- pillar mining systems made it possible to calculate stable parameters for the conventional and innovative mining systems. The study was supported by the Russian Science Foundation, Project No. 19-17-00034.

СТАНОВЛЕНИЕ И РАЗВИТИЕ СПЕЛЕОТЕРАПИИ В МИРОВОЙ ПРАКТИКЕ

Speleotherapy (ST) is a non-drug method of treatment which uses the microclimate of underground spaces. Such spaces may be represented by karst caves, salt mines, rock-salt and metal mine workings. The specific environment of underground spaces is the main factor affecting the patient's body. Speleoenvironment is formed by the combination of medical and health-improving components. Microfine salt aerosol is the main component of the speleoenvironment. It is based on the light negative ions arising at high levels of air ionization. The other components of the speleoenvironment are the constancy of the microclimate, temperature background, humidity, air flow rate. Another important factors are the absence of allergens and low bacterial contamination. Shielding effect ot the underground space, protecting from the exposure to radio-magnetic radiation is also mentioned. The main stages of the formation and development of the ST method in the world practice are also discussed in the article. Various types of speleological hospitals and the peculiarities of their geographic location are described. The factors of the speleoenvironment are presented. These factors affect the patient's body if the method is used under various conditions.

SALT MINING IN GALICIA (1867 – 1900)

The purpose of the article is a generalized study of rock and table salt mining in Galicia during the Austro-Hungarian period. To achieve this goal, general historical approaches to statistical interpretation of events and phenomena, mathematical methods of modelling have been used. The Research Methodology is based on the principles of historicism, objectivity, the use of historical comparative, historical systemic, analytical synthetic, biographical, statistical methods, as well as the methods of personalization and source studies, the archival analysis of documents. The scientific novelty consists in a complex analysis of salt mining in some administrative territorial formations of Austria. The Conclusions. The development of salt deposits in Galicia along the north-eastern edge of the Carpathians had continued since the Middle Ages, but reached its prosperity during the Austro-Hungarian Empire. During the second half of the XIXth century the main producers of salt were the saltworks in Bolekhiv, Bochnia, Wieliczka, Deliatyn, Dolyna, Drohobych, Kosiv, Lacko, Lanchyn, Stebnyk and Kachytsia. In 1868 – 1880 the saltworks of Galicia, with the exception of Wieliczka (36 – 63 thousand tons) and Bochnia (15 – 20 thousand tons), produced an average of 4 – 7,5 thousand tons of salt per year. During the last quarter of the XIXth century 9 – 13 kg of salt was produced per 1 inhabitant, which was twice more than the natural needs of a human being for his consumption. About 50,000 tons of salt were used per year in Galicia. In addition, less than 23 thousand tons were used for livestock. The saltworks in Wieliczka and Bochnia were the largest salt producers. Wieliczka produced more salt than all other saltworks in Galicia (maximum in 1872 – more than 75,8 thousand tons). At the beginning of the 1870-ies there was the maximum of salt production, except for Lacko and Stebnyk, where there was a gradual increase in production during 25 years. During the years of 1868 – 1892, the saltworks of Galicia produced the following amount of salt (tons) per year: Bolekhiv – 5877; Bohnia – 14521; Wieliczka – 42697; Deliatyn – 4047; Dolyna – 4934; Drohobych – 4834; Kalush – 3832; Kosiv – 4329; Lacko – 6240; Lanchyn – 4032; Stebnyk – 6734. Two saltworks in Western Galicia (Bochnia, Wieliczka) produced 57% of all Galician salt production during 25 years, while nine saltworks in Eastern Galicia produced only 43%. The introduction of a salt monopoly in Austria-Hungary reduced its value and revenues to the Galician budget. If in 1832 salt exports brought in revenue of 1,4 million zol., during the 1890-ies – only 0,1 million zol. more. In 1892 the value of Galician salt was: rock salt – 4,5 million, table salt – 4 million zol. rynskykh. During the period of 1868 – 1892, almost 3 million tons of salt were produced in Galicia with a total value of 2,4 million zol. rynskykh. The average price was 0,8 zol. per 1 kg of a ready-made product. The share of Galicia in the salt industry of Austria-Hungary was 44% by volume and 43,5% – by value of products. The fact is striking, first of all, that the total monetary price of all salt products had been significantly underestimated since 1872, when its monetary price of all salt products amounted to more than 12 million zol. rynskykh, while in 1892 – it did not reach even 8 million. This price was caused by the Austro-Hungarian agreement of June 7, 1868, when the sale price of salt was lowered by 0,5 zol. rynskykh per 1 ton. In total, during 1868 – 1892 Galicia produced 2,997 million tons of salt (annually – 1,2 million tons) of all varieties worth 237 million zol. rynskykh or 9,5 million per year. Expenditures for the same period amounted to 22,6 or annually – 1 million zol. rynskykh. In general, the salt industry of Galicia was highly profitable – the income amounted to more than 210 million zol. rynskykh (8,5 million zlotys. rynskykh – per year).

Predicting mining-induced dynamic deformations for drilling solution rock salt mine based on probability integral method and weibull temporal function

ABSTRACT Long-term dynamic monitoring and sustainable prediction of rock salt mines is extremely important in preventing potential geological damages. However, the future prediction of the mining-induced surface displacement after the underground mining extraction cannot be achieved with single Multi-Temporal Differential Interferometric Synthetic Aperture Radar (MT-InSAR) technique, which can only reveal the deformation history during the period of Synthetic Aperture Radar (SAR) acquisition dates. In this paper, a novel dynamic model, namely Dynamic Probability Integral Method (DPIM), based on the integration of Probability Integral Method (PIM) and Weibull temporal function, is proposed in order to predict the future dynamic subsidence for the period which can not covered by the SAR acquisitions. Firstly, the time series deformation over the test salt mine are generated by Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technique with use of 43 Sentinel-1 images, and then the functional relationship between the derived deformation and DPIM is established; Subsequently, the unknown parameters, including the PIM parameters and the Weibull temporal parameters are estimated following the genetic algorithm; Finally, the dynamic surface deformation occurring during the entire period of the underground extraction of the test rock salt mine is predicted. Both simulation and real deformation data over Xinhua (a typical rock salt mine in Hunan province, China) have been investigated. The scenario using the simulated data shows that the overall root-mean-square error of DPIM-predicted subsidence is ±3 mm. The real data experimental results show that the maximum predicted vertical subsidence over the rock salt mine was up to 246 mm. The root-mean-square error with comparison to the levelling measurements is estimated as ±7 mm.

PELATIHAN PEMBUATAN PRODUK KECANTIKAN BERBAHAN DASAR GARAM LAUT DI DESA LAMPANAH, ACEH BESAR

Salt is a chemical compound that is generally derived from sea water, with the chemical name Sodium Chloride (NaCl). Salt can be obtained in three ways, namely through evaporation of seawater by sunlight, rock mining (rock salt mining) and from brine wells (brine). Lampanah Village is one of the Villages located on the coast of Kabuoaten Aceh Besar, with the majority of its residents living as salt farmers. The implementation of the training program for making beauty products made from sea salt was carried out in Lampanah Village, Aceh Besar District. The training method used in the utilization of sea salt consists of 2 stages, namely extracting information about salt and training and direct practice of processing sea-based products into spa salt, salt masks and salt face scrubs. improve the skills of salt farmers in Lampanah Village, Aceh Besar in processing salt into high-value-selling products. These products include salt masks, salt scrubs and spa salts. In addition, it is hoped that these products will become local products typical of Lampanah Village, Aceh Besar.

The hydrogeological situation after salt-mine collapses at Solotvyno, Ukraine

Study regionThe study site is located in the south-western part of the Ukraine, in the area of the historical rock-salt mining town Solotvyno. The former mining area is situated in close vicinity to the River Tisza, the main tributary of the Danube River, the largest river in Europe. Study focusAfter uncontrolled flooding of several salt mines, a one month advisory mission was launched by the European Commission to estimate the impact of the abandoned salt mines (containing large quantities of salt water) on the environment. As a consequence of the flooding, dozens of sinkholes formed and sinkhole forming processes are ongoing, with sinkhole diameters reaching 250 m. As river contamination by the release of large quantities of saltwater would lead to an international disaster, hydrogeological measurements were taken on-site to study the system. New hydrological insights of the regionAt the study site, saturated (hyper-saline) water as well as fresh surface and groundwater were encountered in close vicinity to each other. Electrical conductivity, as a proxy for salinity, and temperature were measured on-site and water samples taken from surface-, ground- and mine waters were analyzed for chemistry and stable isotopes, providing new insights into groundwater flow dynamics. A conceptual model shows the salt dome, and potential flow paths from the mining area to the Tisza River, in the context of the mines and associated sinkholes potentially impacting the river water quality.

Substantiation of convergent technology data for the Ilets rock salt mining

Using the applied theory of honeycomb structures, the authors propose and evaluate mining system alternates based on the structure of honeycombs for a rock salt deposit. The new-developed nature-like convergent geotechnology enables the loss of the useful mineral to be reduced from 40–60% to 15% at the preserved geodynamic safety of mining. The scope of the discussion embraces the variants of ore extraction from vertical stopes bottom-up using assemblies of mechanized equipment and top-down with a mechanical device reaming a pilot hole for useful mineral to be by-passed to an accumulation horizon.

Mining-Induced Time-Series Deformation Investigation Based on SBAS-InSAR Technique: A Case Study of Drilling Water Solution Rock Salt Mine.

Compared to traditional coal mines, the mining-induced dynamic deformation of drilling solution mining activities may result in even more serious damage to surface buildings and infrastructures due to the different exploitation mode. Therefore, long-term dynamic monitoring and analysis of rock salt mines is extremely important for preventing potential geological damages. In this work, the small baseline subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technique with Sentinel−1A imagery is utilized to monitor the ground surface deformation of a rock salt mining area. The time-series analysis is carried out to obtain the spatial–temporal characteristics of land subsidence caused by drilling solution mining activities. A typical rock salt mine in Changde, China is selected as the test site. Twenty-four scenes of Sentinel−1A image data acquired from June 2015 to January 2017 are used to obtain the time-series subsidence of the test mine. The temporal–spatial evolution of the derived settlement funnels is revealed. The time-series deformation on typical feature points has been analyzed. Experimental results show that the obtained drilling solution mining-induced subsidence has a spatial characteristic of multiplied peaks along the transversal direction. Temporally, the large-scale surface settlement for the rock salt mine area begins to appear in September 2016, with a time lag of 8 months, and shows an obvious seasonal fluctuation. The maximum cumulative subsidence is detected up to 199 mm. These subsiding characteristics are consistent with the connected groove mining method used in drilling water solution mines. To evaluate the reliability of the results, the SBAS-derived results are compared with the field-leveling measurements. The estimated root mean square error (RMSE) of ±11 mm indicates a high consistency.