Papers by Violeta Stefanova
Geologica Macedonica
The Tikveš Paleogene basin is located in the central part of the territory of Macedonia and belon... more The Tikveš Paleogene basin is located in the central part of the territory of Macedonia and belongs to the central part of the Vardar zone. The flora collected in the sandstone-clay sediments from the lower flysch lithozone from the Serta locality (Tikveš basin) has been recorded and described for the first time in Macedonia. One species from the fossil flora has been identified as Equisetum parlatorii. These new findings provide information on the past and present distribution and history of Equisetum and exemplify the importance of biogeographic and evolutionary processes in the geological past. As one of the reasons for the reduction in the size of today's Equisetum from the recent vegetation, the significant climatic changes that were the result of the Himalayan orogeny during the Late Miocene are assumed.
The area of the Mariovo coal deposit is located in the southeastern part of the Republic of Maced... more The area of the Mariovo coal deposit is located in the southeastern part of the Republic of Macedonia, about 46 km SE of the town of Prilep. It comprises the border area between the Vardar zone and the Pelagonia massif (Fig. 1)
Примена на геохемијата на стрим седиментите при проспекциските истражувања
Користењето на геохемијата на стрим седиментите повеќе од половина век покажува дека е метода за ... more Користењето на геохемијата на стрим седиментите повеќе од половина век покажува дека е метода за утврдување на потенцијалот на тешките минерали. Основната премиса е дека стрим седиментите настануваат како резултат на распаѓањето и ерозијата низводно на испитуваниот терен. Сепак, деталните истражувања покажуваат дека со оваа премиса на големо се поедноставува реалната ситуација. Особено флувијалните процеси кои доведуваат до создавање на стрим седиментите и нивното сортирање силно влијаат на составот и репрезентативноста на стрим седиментите. Така на пример обична поплава може да ги однесат стрим седиментите така да не остане ваков материјал на испитуваните места или донесувањето на нови седименти може да биде од неколку извори чија активност варира во текот на времето. Снабдувањето на седимените може да биде нарушено со земјоделски активности.
Geologica Carpathica, Proceedings of the XVII Congress of Carpation-Balkan geological association, 2002
Latest field and laboratory investigations carried out in the Fe-Ti mineralization in the vicinit... more Latest field and laboratory investigations carried out in the Fe-Ti mineralization in the vicinity of Brezovec offered new data about the type of mineralization related to the metagabbro rocks. Microscopic and electrono microprobe studies made it possible to obtain new information about the properties of the major minerals, their major ore minerals, their textures and structures.
This paper shows protective measures should be taken to carry out preventive protection of ground... more This paper shows protective measures should be taken to carry out preventive protection of groundwater from the artesian aquifer in locality Raotince. Based on research by two hydrogeological exploitation investigative boreholes artesian aquifer with poorly mineralized water is noticed in Kvarter-Pleistocene lake sediments with two aquifer layers.
Tehnika, 2014
This paper presents the latest results from gold panning which was performed along the creek Meck... more This paper presents the latest results from gold panning which was performed along the creek Meckin Dol. Research showed that the size of the tested gold aggregates ranges from 30 microns to about 600 microns, and the most frequently present form of gold aggregates was isometric-irregularform. The chemical composition of gold aggregates shows heterogeneity with an average gold content ranging from 74.15%-99.32%, followed by silver with an average content of 0.3%-24.68%,and an average copper content of 0.04 to 11.06%. Other impurities such as Fe, Bi, Se, and Te are represented with content less than 1%. In general it can be said that the examined gold aggregates, by their chemical composition, are characterized by high purity ranging from 750 to 996.
This paper deals with the analysis of basic geotechnical properties of monolithic rock samples fr... more This paper deals with the analysis of basic geotechnical properties of monolithic rock samples from several metallic mineral deposits in the Republic of Macedonia. Namely, results from geotechnical investigation on samples from the deposits of Ilovica, Borov Dol, Kazan Dol, Plavica, Kadiica and Bu im were subject of the work presented herein. Over 800 different geotechnical tests have been performed on samples from different depths and zones of these deposits. The most frequently performed basic tests during geotechnical investigation phases included: point load index tests, unconfined compression tests, unit and specific weight, porosity, shear strength along joints. All data is statistically analyzed and certain conclusions for different geotechnical parameters are achieved. Special attention is paid to the vertical distribution of the parameter's values, since this is of greatest interest for the mining planning and processes. Differences among certain deposits are discussed and certain conclusions and recommendations for further investigations are presented. We note that this is a first attempt to analyze such amount of geotechnical data from metallic mineral deposits in Macedonia, and the herein presented correlations are to be updated as new data is collected.
The Kožuf volcanic massif is disposed in the frame of the Vardar zone. The volcanic and volcano-s... more The Kožuf volcanic massif is disposed in the frame of the Vardar zone. The volcanic and volcano-sedimentary rocks from the “complex of Pliocene sediments and pyroclasts” overlay the metamorphic (Precambrian and Paleozoic) and sedimentary (Triassic to Upper Eocene) rocks of the region (Jankovic et al. 1997; Boev & Jelenkovic, 2012). The Pliocene volcanic and volcano-sedimentary rocks occur as layers in a lacustrin basin and subvolcanic bodies crosscutting the older rocks (Triassic carbonates; Percial, Radke, 1994; Boev & Jelenkovic ...
Законот за води (Сл. Вес. На Р.М. бр. 87/08) ги дава законските основи за искористување на водите... more Законот за води (Сл. Вес. На Р.М. бр. 87/08) ги дава законските основи за искористување на водите, заштитата на водите и заштита од штетното делување на водата и претставува основен документ за управување со водите во Република Македонија. Според законот за води со членовите 96, 97, 98, 99 и 100 е регулиран начинот на кој треба да се заштитат водите кои се наменти за консумирање од страна на човекот. Во член 96 од овој закон се наведуваат сите видови на водни тела околу кои треба да се одредат заштитините зони. Со овој член со ставот еден се укажува дека за превентивна заштита на водните тела кои се користат за консумирање од човекот треба да се одредуваат заштитни зони. Понатаму во член 98 се укажува дека водното тело кое што се користи за снабдување со вода наменета за консумирање од страна на човекот се заштитува преку воспоставување и одржување на потесна или зона на строг санитарен надзор и една или повеќе пошироки заштитни зони
This paper presents the results of the detailed field and laboratory investigations of gabbro fro... more This paper presents the results of the detailed field and laboratory investigations of gabbro from the locality Pantelej. These investigations are conducted in order to determine the mineralogical-petrographic and technical characteristics of gabrro in order to use as construction stone. The main minerals that build rock are plagioclase and pyroxene. Pyroxene is the dominant mineral in this sample, and it is represented by about 80%. In most pirochsene crystals are occupied with the process of metamorphosis - uralitisation where they transform to amfibol type: actinolite- tremolit and uralit. Plagioclase in terms of pyroxene is present in smaller quantities and represented approximately 20%. It occurs like allotriomorphic to hypidiomorphic crystal belongs to basic plagioclase. For the determination of the possibilities for the exploitation of this gabbro as constructing- technical stones, were carried out mineralogical - petrographic and chemical research, as well as, determine the ...
Kožuf metallogenic district is significantly affected by former exploration and exploitation whic... more Kožuf metallogenic district is significantly affected by former exploration and exploitation which lead to increased concentrations of heavy metals in individual environmental components. These metals can enter into water environment by leaching, acid main drainage, erosion and sedimentation. Water and soil analyses of Kozuf metallogenic district performed by the team of Faculty of Natural and Technical Sciences (University "Goce Delčev"-Štip, Macedonia) and GIS-GEOINDUSTRY (Czech Republic) in 2013 detected increased concentrations of Sb, As and Tl. Health risks of these metals in drinking water as well as their legal limits are discussed.
Studied zeolite bearing tuff from the Vetunica deposit is localized in northern marginal parts of... more Studied zeolite bearing tuff from the Vetunica deposit is localized in northern marginal parts of the well known Kratovo-Zletovo volcanic area (Republic of Macedonia). Zeolite bearing tuff occupies the shallowest parts of the Tertiary volcanic rocks complex in this area. The stilbite (NaCa 2 Al 5 Si 13 O 36 · 14H 2 O) was determined within the aforementioned zeolite bearing tuff. In our detailed study we found out that in the Vetunica deposit stilbite is present with 27%. Also, cation exchange capacity (CEC) and ammonium exchange capacity (AEC) values for samples from the Vetunica deposits are in the range of 94-102 meq/100 g for CECs and 109-114 meq/100 g for AECs. All the values show that these tuffs could be very effective in a wide range of applications such as waste water ammonium removal, in animal nutritions, fertilizers, fish farming, additives to cement and others. Geochemical data illustrates high concentrations >30 ppm As, 1 g/t Ag, 70 g/t Pb, 17 g/t B etc., as representative elements for this volcanic area.
ne of the major emission sources of some metals in the eastern part of the R. Macedonia is Bucim ... more ne of the major emission sources of some metals in the eastern part of the R. Macedonia is Bucim copper mine and flotation, near the town of Radovis. Ore excavation is from open pit and the ore tailings are stored in the open, in mine vicinity. The produced copper ore from the mine is processed in the flotation plant; after the flotation of copper minerals, the flotation tailings are separated, disposed of and deposited on a dump site in an adjacent valley near the village Topolnica. During the 35 years of continuous exploitation around the Buchim Mine was created surface waste dump were have been stored more than 150 Mt and more than 100 Mt material within the hydrotailling dam. Within this study a total content of 20 elements was determined in soil samples taken from the vicinity of the "Bucim" mine, covering an area of 14.2 km 2. Analyses were performed by the ICP-AES. The results have been compared to new Dutchlist and NOAA standards and the following was concluded: As values ranged 13.1÷225 mg kg-1 with 20 samples above the optimum (29 mg kg-1 As) and 7 above action value (55 mg kg-1 As), in that context Cd values ranged 0.67÷17.9 mg kg-1 with 17 values above optimum (0.8 mg kg-1 Cd) and 1 over the action value (12 mg kg-1 Cd), Cr with range 30.1÷171 mg kg-1 with 6 over optimal value (100 mg kg-1 Cr) and none above action value (380 mg kg-1 Cr), Cu with range 17.8÷1734 mg kg-1 with 16 over optimal value (36 mg kg-1 Cu) and 3 above action value (190 mg kg-1 Cu), Ni with range 9.8÷69.4 mg kg-1 with 5 over optimal value (35 mg kg-1 Ni) and none above action value (210 mg kg-1 Ni), Pb with range 46÷3456 mg kg-1 with 19 over optimal value (85 mg kg-1 Pb) and 1 above action value (530 mg kg-1 Pb), Zn with range 88÷3438 mg kg-1 with 12 over optimal value (140 mg kg-1 Zn) and 1 above action value (720 mg kg-1 Zn), Mn with range 169÷998 mg kg-1 with 25 over optimal value (33 mg kg-1 Mn) and none above action value (48 mg kg-1 Mn), Fe range 0.73÷5.02% with 21 over optimal value (1.8% Fe) and none above action value (3.2% Fe). The V, Al, Co, also, showed some increased values, but not more than optimal concentration.
Within these trials were treated results of 288 lithogeochemistry and 362 soil samples. Gold, sil... more Within these trials were treated results of 288 lithogeochemistry and 362 soil samples. Gold, silver and arsenic were the elements selected for the geochemical interpretation in the Surfer software package. Gold anomalies in lithogeochemical samples ranged from 0.31 up to 19 ppm Au while in the soil samples concentrations ranged 1-5 ppm Au. Silver anomaly values, in soil samples, were within the range 0.34 ÷ 19 ppm Ag and for arsenic values were 4÷2001 ppm As. Mercury, antimony and thallium were enclosed within this geochemical study, but however they were not taken into consideration for the Surfer helped interpretation. The 3D model displays the hypsometric difference in the distribution of gold of 170 m, from level 730 m up to level 900 m. Lithogeochemitry map of gold shows linear orientation of anomalous concentrations probably due to deposition of gold along the fault structures of northwest direction.
The productive ore mineralization within the Kozuf metallogenic area, mainly, has been related to... more The productive ore mineralization within the Kozuf metallogenic area, mainly, has been related to the Alpine metallogenic epoch while spatial and temporal has been spread during the Cretaceous stage and Pliocene period. During the Cretaceous metallogeny were formed several iron and nickel deposits related to the redeposited lateritic crusts developed over the Jurassic ultrabasic rocks (dunite, harzburgite, lherzolite). The most important lateritic crust mineralizations were determined in the Rzanovo ore deposit (40 Mt so 1.1% Ni), as well as occurrences at Studena Voda, Gradiste, Rakle and Nikodin. During the late Alpine metallogenic epoch in the Kozuf area were formed polymetallic Cu-Au-Sb-As-Tl-Pb-Zn mineralizations in Alshar and Dudica deposits, related to the Pliocene magmatism (6.0-1.8 Ma) and ring-radial structures related to that particular volcanism. Carlin-type gold (> 1 g/t Au), was determined in parts of the Alshar deposit.
Presented study summarizes results of field sampling campaign performed in 8-10 th of April 2013 ... more Presented study summarizes results of field sampling campaign performed in 8-10 th of April 2013 being part of the CEI funded project "Environmental Impact assessment of the Kozuf metallogenic district in southern Macedonia in relation to groundwater resources, surface waters, soils and socioeconomic consequences (ENIGMA)." The campaign included identification of surface and ground water bodies and sources in the catchments of Alshar and Dudica areas. There were in situ measurements of physical parameters performed and consequently samples taken for identification of heavy metal distribution in flow pathways.
In R. Macedonia there are a number of occurrences of gold more or less been studied. One of the m... more In R. Macedonia there are a number of occurrences of gold more or less been studied. One of the methods used in prospection of potential localities is schlich method. In this paper presents the results of preliminary schlich prospection which was performed along the river Lukar and Stara Reka in Kozuf volcanic area that is associated with Tertiary magmatizam in R. Macedonia. Tests showed the presence of gold in taken schlich characterized by irregular shape.
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Papers by Violeta Stefanova