Leveraging active-source seismic data in mining tailings: Refraction and MASW analysis, elastic parameters, and hydrogeological conditions

We applied active-source seismic method for the interpretation of elastic parameters in tailings facilities which is essential for evaluating stability and seismic response. The methodology uses different analysis methods on the same dataset, i.e., conventional seismic refraction (SR) to determine compressional-wave velocity (Vp) and multichannel analysis of surface wave (MASW) to estimate shear-wave velocity (Vs). Seismic velocities in conjunction with tailings physics approach revealed interpretable data in terms of elastic parameters and hydrogeological conditions. The results determined the empirical linear relationships between Vp and Vs that are particular to an unconsolidated media such as tailings and showed that variability of hydrogeological conditions influences the elastic seismic response (Vp and Vs) and the elastic parameters. The analysis of the elastic parameters identified the state condition of the tailings at the time of the survey. The Bulk modulus K that relates the change in hydrostatic stress to the volumetric strain was predominant between 1.0−2.0 GPa. The Young’s modulus E in the tailings media was in the low range of 0.15−0.23 GPa. Poisson’s ratio values in all sections were in the upper limit in the range of 0.37−0.49, meaning that the tailings media is highly susceptible to transverse deformation under axial compression.

Analysis of the hydrogeological conditions in Bulgaria in connection with the radon potential

Natural radon (222Rn) is a radioactive noble gas that occurs in every rock or soil due to the content of radium (226Ra), part of the 238U family, in the lithosphere. Different types of rocks and soils possess different 226Ra content and different permeability. Radon has high mobility and is driven by diffusion and convection with the soil gas throughout connected and water-unsaturated pores and/or cracks in permeable rocks and soils. Therefore, the radon potential of the area could depend on hydrogeology and its particular settings. The study deals with the general characteristics of the groundwater depths in Bulgaria based on the published since 1960’s sources. After analysis of the collected data several distinct regions have been elaborated based on different depth of the groundwater table regarding lithological, tectonic and geomorphological conditions. In addition, zones for screening assessment of groundwater table influence of radon potential have been precised.

Features of the subsurface water composition formation in the Mesozoic hydrogeological basin of the Middle Ob region fields

The formation of the deep oil and gas bearing horizons hydrogeological conditions in the Middle Ob region and the West Siberian megabasin as a whole contains many questions and is a subject of discussion. This is due to numerous hydrogeodynamic and hydrogeochemical anomalies that do not have an unambiguous explanation. The hydrogeological conditions feature of the area under consideration is inversion hydrogeochemical zonation in the Lower Cretaceous and Upper Jurassic sediments, as well as the presence of low-mineralized formation waters of hydrocarbonate-sodium composition. The change in the genetic type of waters, the mineralization decrease, the calcium ion content decrease and an increase in the hydrocarbonate ion amount in the Mesozoic hydrogeological basin, is associated with the transformation of mineral and organic matter in sedimentary rocks during their immersion, occurring at the elision stage of the basin development.

Geological and tectonic preconditions for hydraulic heterogeneity of the rocks in the area of the Gotse Delchev valley

Hydrogeological conditions largely depend on the permeability of the geological environment. In areas with complex geological and tectonic conditions, the detection of hydraulic heterogeneity of the rocks and determination of groundwater-rich zones is a challenge for hydrogeological practice. The aim of the study is to analyze the geological and tectonic prerequisites for hydraulic heterogeneity of the sediments for the Gotse Delchev valley (Southwestern Bulgaria), which predetermine the degree of their water productivity. In order to obtain more precise data for specific sites, a geophysical survey was conducted. The Self-Potential method was chosen, which is one of the most commonly used techniques for applications for hydrogeological purposes. The results of the geophysical survey carried out in selected sites allowed to locate groundwater-rich zones, to establish the depth of occurrence of hard low permeable rocks, as well as to confirm the presence of faults.

Hydrogeological Conditions of Qazaniyah Sub-basin in Diyala / Iraq

The study area is located in the eastern part of the Diyala Governorate close to the Iraqi-Iranian border. This study was set to investigate the hydrogeological calculations of northeast of Qazaniyah wells where the groundwater moves in directions of from the northeastern parts towards the southwestern par, that is, the same direction of the topography and the same direction of the tendency of the layers t. The study‘s region is characterized by visible geological layers or those that can be penetrated to a reasonable depth by wells which are sedimentary rocks deposited in continental or semi-continental conditions in the bays. From the study of the hydraulic properties of the two hydrogeological and exemplary systems, the values of transmissivity, permeability and storage coefficient are ranged between 1.94- 5.73 m2/day, 1.02- 3.92 m/day and1.40 x 10-5- 2.62 x 10-4, respectively. While the estimated value of transmissivities, which are obtained from specific capacity, ranged between 6.27- 8.62 m2/day. This variance in the values indicates the broad differences in the values Lithology of aquifers, which seems to be influenced by the strength and the number of fractures and joints.

ASSESSMENT OF CHANGES IN THE HYDROGEOLOGICAL CONDITIONS CAUSED BY WET-BASED CONSERVATION OF THE STYLSKYI QUARRY OPERATED BY “DOKUCHAEVSK FLUX AND DOLOMITE COMPLEX” PJSC USING MATHEMATICAL MODELLING

Extraction of minerals significantly affects the hydrogeological conditions of the environment. Active development of mining operations in the Donbas region determined the dominant influence of technogenic changes in geological environment on the formation of modern ecological conditions in the region. This applies not only to coal mining but also raw materials extraction (dolomites, limestone) for metallurgical plants mostly by quarrying. Recently, a significant environmental problem in the region has been the mines and quarries closure, envisaged by the program for restructuring the coal industry of Ukraine. Closure of mines or quarries through wet-based conservation is the least financially expensive, although it significantly increases the technogenic load on the natural environment. The object of research involved groundwater and surface water within the area of the Stylskyi and Skhidnyi (Vostochnyi) quarries of the “Dokuchaevsk flux-dolomite complex” PJSC, as well as Kipucha Krynytsa and Shevchenkivskyi water intake structures. The goal of research was to forecast changes in the hydrogeological conditions under the influence of wet-based conservation of the Stylskyi quarry. To achieve this goal, hydrogeological methods, mathematical modelling, and expert assessments were used. Consequently, a hydrogeological model of the research area was created, its functional correspondence to the natural-anthropogenic conditions was confirmed, and calculation hydrogeological parameters were specified. As a result, the forecast of changes in the hydrogeological conditions under the influence of wet-based conservation of the Stylskyi quarry was made. In particular, the following issues were determined: the dynamics of quarry flooding; the influence of this process on changes in water inflows to the Skhidnyi (Vostochnyi) quarry, Kipucha Krynytsa and Shevchenkivskyi water intake structures; possible flooding of settlements and swamping of the research area; changes in chemical composition and groundwater salinity; time of quarry draining at various intensity of water outflow to resume mineral production in case of need. We would like to emphasize that the forecasts made should be used when designing partial or full flooding of the Stylskyi quarry.