Andra-Elena Filiuță

The five-element mineralization of the Bihor metallogenetic district, Apuseni Mts., Romania contains three identifiable depositional stages, recording Co-fluctuations during a continuous increase of sulfur activity. Gersdorffite forming several chemical clusters precipitates overprinting a diarsenide-rich stage, later growing abundantly as krutovite-gersdorffite with nickeline, and replacing at different extents earlier assemblages. A Raman investigation on gersdorffites and accompanying phases revealed distinctive spectra. The compositional clusters of gersdorffite correlate with the Raman response, allowing the separation of near-stoichiometric gersdorffite, As-rich paragersdorffite and Co-Ni – substituted paragersdorffite.

Large platy symplectitic aggregates composed of corundum and albite appear in quartz veins crosscutting heavily retrogressed eclogites in the Căpățâna Mountains, South Carpathians. They were identified as pseudomorphs after kyanite initially formed in the veins. Protracted circulation of reactive fluids of alkaline composition along the veins produced corundum-forming breakdown of kyanite. Sluggish aluminium silicate – forming reaction between quartz and corundum enabled metastable coexistence of the two incompatible minerals, which were nevertheless found separated by a seam of biotite rather than in direct contact.

Mining activities often generate important amounts of extractive waste, and, as a consequence, environmental impacts that affect all factors to a greater or lesser extent. Depending on a variety of variables, the impact can be permanent or temporary, reversible or irreversible, negative or positive. This study conducted research on the status of closure and remediation processes of mining areas in Romania, specifically in the counties of Maramureș, Suceava, Harghita, Alba, Hunedoara and Caraș-Severin. Furthermore, based on the type and level of pollution, the degree of application of remediation techniques for water and soil pollution in the investigated mining areas was studied. From the analysed information, it is evident that although the closure and remediation process started in Romania over 20 years ago, unfortunately, to this day, the technical projects, technical assistance, and execution of closure and remediation works have not yet completely solved the complex environmental issues in the mining sector. Most of the tailing ponds and waste piles of former mines continue to pose permanent specific risks to the environment and the population. This study concludes that the mining sector in Romania, although it has the necessary techniques and technologies for the ecological rehabilitation of degraded lands related to the Extractive Waste Facilities and the elimination of negative impacts on the environment and public health, has not yet been able to fully concretize its remediation efforts.

An ammonium-bearing fluorapophyllite-(K) occurs as a late hydrothermal product in the outer endoskarn zone from Aleului Valley (N 46°37′04″, E 22°35′22″), located at the contact of the granodiorite laccolith from Pietroasa, of Upper Cretaceous age, with Anisian dolostones. Associated minerals are wollastonite, K feldspar, diopside, fluorapatite, talc, and pectolite. The chemical structural formula is [K_0.985Na_0.012(NH₄)_0.076]_Σ=1.073(Ca_4.009Mn_0.001Fe²⁺_0.003Mg_0.002Ba_0.001)_Σ=4.016(Si_7.953Al_0.047) O_20.029[F_0.899(OH)_0.101]·8.059H₂O. The structure was successfully refined as tetragonal, space group P4/mnc, with cell parameters of a = 8.9685(1) Å and c = 15.7885(5) Å. The indices of refraction are ω = 1.534(1) and ε = 1.536(1). The calculated density is D_x = 2.381 g/cm³, in good agreement with the measured density, D_m = 2.379(4) g/cm³. The thermal analysis shows that the mineral completely dehydrates at up to 450 °C (endothermic effects at 330, 371, and 448 °C) and loses ammonium at 634 °C. In the infrared spectra, the multiplicity of the bands assumed to be silicate modes (1ν₁ + 3ν₃ + 2ν₂ + 3ν₄) agrees with the reduction in the symmetry of the SiO₄⁴⁻ ion from T_d to C_δ. Fluorapophyllite-(K) from Aleului Valley is of late hydrothermal origin and crystallized from F-rich fluids originating from the granodiorite intrusion, which mobilized K, Ca, and Si from the pre-existing feldspar.

Mining activities often generate important amounts of extractive waste, and as a consequence, environmental impacts that affects all factors to a greater or lesser extent. Depending on a variety of variables, the impact can be permanent or temporary, reversible or irreversible, negative or positive. This study conducted research on the status of closure and remediation processes of mining areas in Romania, specifically in the counties of Maramureș, Suceava, Harghita, Alba, Hunedoara, and Caraș-Severin. Furthermore, based on the type and level of pollution, the degree of application of remediation techniques for water and soil pollution in the investigated mining areas was studied. From the analysed information, it is evident that although the closure and remediation process started in Romania over 20 years ago, unfortunately, to this day, the technical projects, technical assistance, and execution of closure and remediation works have not yet completely solved the complex environmental issues in the mining sector. Most of the tailing ponds and waste piles of former mines continue to pose permanent specific risk to the environment and the population. This study concludes that the mining sector in Romania, although it has the necessary techniques and technologies for the ecological rehabilitation of degraded lands related to the Extractive Waste Facilities and the elimination of negative impacts on the environment and public health, has not yet been able to fully concretize its remediation efforts.

This study offers a comprehensive analysis of unconventional renewable and sustainable energy production options by tapping into the energy associated with the natural tendency to cancel salinity gradients that occur when salt water and fresh water come into contact. Furthermore, this paper assesses the potential for generating blue energy in Romania by examining historical data on flow rates from relevant fresh water sources, such as the Danube River, and the salt loading of potential receiving water bodies, including salt lakes, and the Black Sea. In addition, this study briefly references pilot-level technologies for blue energy production in other countries, including Norway, Japan, and the European Union. Based on literature data, this paper highlights the most important technological methods with applicative potential for harnessing energy from salinity gradients. The performances and limitations of these methods have been presented, acknowledging that despite recent years of advancements in materials and technologies, large-scale implementation and commercialization efforts are still limited. The analyzed data reveals that Romania possesses substantial potential blue energy resources for both large capacity installations, such as the Danube River-Black Sea with a potential achievable capacity of about 50 MW, as well as smaller capacity devices situated around saline lakes and salt deposits. This study concludes that Romania has a unique opportunity to capitalize on its vast blue energy potential and drive sustainable energy development.