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Mineral resources of the urals: origin, development and environmental impacts.

Deliverables

Assessment of the sulphur budget in the environment included the transects of snow samples (see D26) and demonstrated the widespread distribution of atmospheric sulphur derived from the Karabash smelter. The sulphur isotope study included also the flooded open cast mines ("Pit lakes"), which pose an environmental hazard to the low-lying areas in their vicinity and to groundwater. The XIX Party Congress and Kul Yurt Tau mines were taken as examples of pit lakes. They were sampled during the winter of 2000-2001 from the frozen surface by V. Udachin, who carried out the chemical analysis of the water samples. The sulphur isotope composition of dissolved sulphate shows that it is mostly derived from the sulphides in the ore and host rocks, with a small contribution from atmospheric precipitation. No indication was found for bacterial sulphate reduction within the water column. The geochemistry of the host rock has emerged as the most significant factor in determining the environmental risk associated with these mines. At the XIX Party Congress Mine the host rocks consist of intermediate and basic volcanics and limestones. There the quality of the water approaches that of the Russian Standard for drinking water except for sulphate and cadmium. At Kul Yurt Tau, where the host rocks consist mainly of highly altered acidic volcanics, the sulphate content is similar but the levels of heavy metals are much higher, significantly exceeding the standard. Hence, the nature of the country rock determines its buffering capacity and the natural attenuation characteristics are important in determining the hazard of the "Pit lakes" and other potentially toxic waters. No technical problems were encountered. Metal budget for reactive wastes is being undertaken as part of deliverable D23 and D24.
Multicriteria processing was based on the data already available from the databases at the time of the study. Main Results 1. Interactive Web Interface with geological maps (Cheliabinsk district at 1:1,500,000 and 1: 500,000), deposits, roads, rivers, lakes, environmental samples. This web interface allows to everybody (with authorisation through username, password) to consult available data (http://minurals.ilmeny.ac.ru and also on http://nature.ilmeny.ac.ru). All the data are stored in an Oracle database. The main components are illustrated on following figures. The database is the main result of the project, with a very high complexity and consistency. The web interface allows mainly the visualisation of the database content. 2. ArcView GIS: this GIS is based on the same data than the web interface, plus other data not already implemented in the Oracle database: part of Sibay geological map (1:50,000 scale map), geochemistry of Satka area, gravimetric anomalies of the same area. This GIS allows a geographical treatment and combination of data. The results of data treatment are then easily integrated in the web interface if required. Many other data are under construction: geology of all Bashkortostan republic, geophysics on Uchaly area, drill holes, 1:200,000 geological mapsiKThe implementation of those data is time consuming because of heterogeneity in projection systems, the lack of co-ordinates for many samples and drill holes, the necessity to use unique codes for all geological maps (a unique system L-code is used in the Oracle database, in accordance with the geological commission of Russia). Nevertheless, this information system is now operating and accepted by the various partners. Moreover, this system will serve as a basis for new projects (Nature project at cheliabinsk district level, regional projects with Bashkiria and other regions currently under discussion). In this situation, few multicriteria analyses were possible before the end of the project. To illustrate what could be the further use of this database and GIS, favourability maps for gold and copper have been computed from geology and deposits at scale of Cheliabinsk district. The cross-treatments of geochemistry and gravimetry has been used to defined anomalies on the Satka district. The geological information has also been used in environmental studies for the definition of natural geochemical backgrounds. In a near future, the use of all drill holes will allow a better definition of surface and deep geochemistry. New environmental data will permit a better regional evaluation of pollution. Combination between geology and mineral occurrences and production of thematic maps data about geological formations and mineral occurrences have been processed for the district of Chelyabinsk, in order to calculate the score of each geological formation in respect with is substance content. This is obtained by the calculation of the ratio: [% of Cu deposit contained in a formation]/[the total surface covered by the formation]In others words, the score represents a probability to have one event ( e.g. a copper deposit) in a geological surface. Then, each formation can be mapped in respect with its score. This has been done for [Copper deposits / Geological formations], for [Gold deposits / Geological formations], and for [Main mineral occurrences / Geological formations].
The final project workshop was organised by BRGM in Orleans, the 2nd July, 2003. All the partners of the project were present and each of them did a short presentation of its main technical results. The University of Athens participated also, in the frame of the cluster between MinUrals and ENVIMAN projects. The slide presentation are available on the BRGM's web site at http://minurals.brgm.fr/ A wealth of international publications as well as the participation to several international congresses (6th and 7th SGA meetings, EGS-AGU-EUG Joint Assembly) ensure a large diffusion of the scientific results of MinUrals through the international scientific community. Four web sites are dedicated to the presentation of the project: http://minurals.ilmeny.ac.ru:8001/ The official web site of the project, set up by IMIN, with the web interface to access the GIS and databases http://minurals.brgm.fr/. The BRGM's web site, with all the documentation of the project, the slide shows presented during the final workshop, and a photo gallery. http://www.nhm.ac.uk/mineralogy/minurals/minurals.htm The NHM's web site, with a detailed presentation of geological and environmental results http://www.anrb.ru/geol/MinUrals/ The USC's web site is dedicated to the presentation of the two-geodynamic expeditions organised by USC.
All the data integrated in the GIS represent a complete set of layers for the Chelyabinsk district and for specific sites. Along with the static layers generated as GIS objects (the topography, geology - geological map of Chelyabinsk district at scale 1:500,000 and 1:1,500,000 and geological map of Sibay at scale 1:200,000 etc.), dynamic layers are created from the database, dynamically included by the users through the web interface (deposits and occurrences, drill-holes, samples, etc.). The development of the web interface has been realised with the AspMap server module developed by VDS Technologies. It is accessible at: http://minurals.ilmeny.ac.ru/
Besides its geological interest, the result is very important for the geophysical methodology itself, since its validates the original and time-saving loop/profile/conductor configuration that we tried here: in opposition to preconceived ideas, it appears that a single profile sub-parallel to an elongated sinuous conductor is sufficient for providing a precise 3-D localization of the conductor all along the profile (and not solely where the profile crosses the conductor). This, of course, is only possible with 3-component EM measurements. This finding opens the way to a new and fast layout of EM profiling that could be used (instead of, or in complement with DC methods) whenever an elongated continuous conductor is to be mapped from the surface (e.g. mapping of water-filled karstic drains).
The experts worked out proposals, which were included into the draft of the new Code of the RF “On subsoil”. They concern, in particular, terms of license agreements, auction criteria, payment privileges, responsibility for violation of the law, etc. According to the regulations of the new Code of the RF “On subsoil” it is necessary to introduce the relevant changes into the regional legislative acts, in particular, into the Law of Sverdlovskaya oblast “On subsoil”, the Code of the Republic of Bashkortostan “On subsoil”. Thus correspondence of regional legislation to the federal laws will be provided. In the sphere of environment protection it is necessary to adopt the Concept of development of environmental legislation system of the Russian Federation in accordance with the Environmental Doctrine. The Concept should be based on the Constitution of the RF and the Concept of transition of the Russian Federation to sustainable development and agree with social, economic, demographic and environmental conditions of the transition period. The above-mentioned concept should determine characteristics of subject and methods, goals and tasks, principles of legal regulation of environmental relations. On the basis of this Concept it is necessary to work out the Concept of development of legislation on use and protection of mineral resources and other natural objects. The next aspect is improvement of the Federal law “On environment protection''. It is important to give this law the status of the head act of environmental legislation. The federal laws on land, subsoil, water and other natural resources should also be amended. Taking into account the EU experience, it is necessary to integrate environmental requirements into the acts of civil, tax, financial, administrative legislation, regulating activities of mining enterprises. Improvement of environmental legislation and its realization are tightly connected with development and operation of the system of administrative and legislative measures. It is necessary to increase efficiency of traditional measures, such as setting of environmental standards, licensing, environmental control and expert examination. On the other hand, new administrative measures, which are successfully used in the EU countries, should be introduced. They include environmental impact assessment (EIA), environmental certification, and environmental audit. An important part of improvement of the legislative system in general is development of regional legislation. First of all, it is necessary to prepare the Concept of regional environmental legislation, based on the Concept of sustainable social and economic development of a region, the Concept of development of environmental legislation of the RF, the Environmental Doctrine of the RF. This concept should be coordinated in future with the Concept of development of legislation on natural resources of the RF (that is also to be adopted) and it should take into account social, economic and environmental conditions of the region. The next step is adoption of the head act of regional environmental legislation (for example, in Sverdlovskaya oblast it should be the Oblast law “On environment protection and natural resources use in Sverdlovskaya oblast”). The head acts on use and protection of subsoil and other natural objects should also be prepared in the regions in the nearest future (for example, in Chelyabinskaya oblast there is no regional law on subsoil so far). An important problem in improvement of environmental and natural resources legislation (especially under condition of growing “regionalization”) is optimal combination of federal and regional levels, that is necessary to provide unity of legal regulation of environmental and mining relations. It is important to eliminate overlapping of federal and regional regulations, that often takes place in regional legislative acts on mining and environment protection. In practice it results in decreasing efficiency of legislative regulation, ignoring local environmental, social and economic peculiarities.
This topic has been considered in special books (“Gold deposits of the Ural”, 2001; “Platiniferous deposits of the Ural”, 2002; “Ore formational and ore facial analysis of the massive sulphide deposits in the Ural, 2001”). The complex origin and multi-stage history of formation of these deposits were proved by detailed geological and mineralogical information.The volcanic hosted massive sulphide (VHMS) deposits formed in different geodynamic environments: Sacmara marginal sea, a supra-subduction basin close to the modern Main Uralian Fault, in the basement of West- and East Magnitogorst island arcs, Sybay inter-arc basin, Dombarovka and Mugodjary back arc basin and in some rifting zones at the Eastern marginal basins. Ultramaphic hosted PGE-ferrous deposits and occurrences formed in different stages of the Uralian belt including Precambrian rifting and mostly Paleozoic island arc conditions (Uralian Platiniferous Belt). Gold deposits are located in Palaeozoic western intercontinental paleorifts (Avsyan, Dalnee, Kagan), paleo-oceanic-like spreading zone (Zolotaya Gora, Kirovskoe, Pavlovskoe, Mauk), island arcs and back arc extensional zones, Eastern active continental margin (Kochkar, Gumbeyskoe, Nepryahinskoe, Astaphyevskoe and many others), collisional structure as Main Uralian Fault (Severo-Miasskoe, Altin-Tash, Mindyak). One group of the Cu-porphyry deposits is hosted by diorite and gabbro-diorite massifs in ensimatic island arcs (Salavat and Voznesenskoe). The second one includes Cu-porphyry and Cu-Au-porphyry which are localized in gabbro and gabbro-diorites in extensional zone within collision structures (Novo-Nikolaevskoe, Miheevskoe). The third group composed of Cu-Au-porphyry and Cu-Au-Mo-porphyry is related to intrusives of marginal volcano-plutonic belts (Batalinskoe, Benkalinskoe, Yuzhno-Benkalinskoe).
Ranking the potential of precious metal and porphyry deposits in the South Ural (D3, D4) PGE About nine PGE-bearing ore formations have been defined:- Sulphide-PGE-CuNi (perspective Zaural zone and Norilck deposits); - Low-sulphide PGE-Au-Cu-Ni (f.e.Hudolaz massif in the South Ural); - PGE-chromate in dunite and perydotite (Solovyevoya Gora, Kempirsay and Kraka massifs); - PGE-Ti-magnetite in apatite is rich in gabbro and pyroxenite(Baronskoe and Volkovskoe, and Kusa); - Au-Pt magnetite (Taratash);- VHMS-Pd-Pt (Gay); - Evaporitic-Pt (Prikamskoe); - Black shales-Pt-Au (Kedrovskoe);- Placer-PGE-Au (Middle Urals and some occurrences). This includes more than 24 types of PGE-deposits. The most important types are related to ultramafic massifs, which occur in Tagil and Magnitogosk zones. The PGE potential of this traditional type deposits have been accounted to more than 19,000 t. The resource of Baronskoe new type of the PGE-Ti hosted in apatite rich pyroxenite gabbro massifs should account to about 5,000 t and black shale hosted deposits could contain about 4,500 t PGE. The resource of other types, including Cu-sandstones and Cu-Ni weathered ultramaphic crusts, are about 10,000 t PGE. Several key PGE-bearing objects have being revised at the boundaries of the Pt-Pd Urals Belts: Nizhni-Tagil, Kachkanar and Pavda mafic ultramafic complexes, and also Uktus mafic ultramafic complex. The additional sampling of Cr-Pt ore of Sirkvosky, Alexandrovsky, Krutoi Log and Gosshakta areas will allow getting new information on breccia like and sideritic ores. Much work in this project has also been dedicated to the recently discovered Au-Pd deposits in the gabbro-diorite of the Tagil-Barancha massif (Au+Pd+Pt grade is 1.2-3.9 ppm). The structural, mineralogical and geochemical studies have been implemented to develop ranking of the PGE deposits. Gold The big gold deposits are typical for island-arc and active continental margin. The biggest gold deposits, located inside long-lived collision zones, generally appear to be polymorphous and polychronic objects that had a difficult and multi-stage formation history, being described in new book devoted to the Urals gold deposits. They commonly contain polymineral ores, and are composed of altered pre-mineralisation rocks and geochemical haloes. The foundation of the Urals mineral wealth consists of quartz-vein, massive-sulphide, gold-massive-sulphide and placer deposits as well as non-traditional objects such as Vorontsovskoye, Gagarskoye, and Svetlinskoye. VHMS deposits (80%), gold-quartz vein type (20%) and some still not exploited new gold iVbearing Cu-porphyry deposits represent the most important potential for gold in the South Urals. The VHMS deposits have been ranked by grades of Au: Baymak (Kuroko) type (2-12ppm) Uralian (Noranda) type ( 1-4ppm) Dombarovskiy (Cyprus) (as a rule less 1ppm). A new gold-bearing paleo-hydrothermal system, Lisi Gory, formed in an andesite-basalt complex of the East-Magnitogorsk (Gumbyskaya zone) island arc, was discovered by the IMIN team through analysis of the distribution, structure and composition of silica-ferruginous rocks and iron-hydroxide gossans. The paleo-hydrothermal Lisi Gory field was formed in a final stage of andesite-basalt volcanism of the Gumbeiskaya suite and soon after it. Further new discovery of gold-deposits in Gumbeyskaya zone can be anticipated. Porphyry-type deposits The Uralian region is a potentially important economic porphyry copper province. Copper reserves in some deposits exceed 1-3 Mt with grades 0.3-0.6% Cu. Deposits with grade of 0.3% Cu are very common too (Salavat - 0.5Mt and Myheevskoe ¡V 1Mt). However, gold grade in these deposits does not exceed 0.3-0.5 ppm. Some ore fields are characterized not only by Au-Cu, Au-Mo-Cu, Cu-Au and Cu-Au-Mo stringer-disseminated mineralization but also by the related polymetallic mineralization (stockworks in silicate rock and massive sulfide ore hosted in marble, skarn and gold-quartz mineralisation). The most economically important potential is anticipated for the Au-Cu-porphyry and Au-Cu-Mo-Porpyry deposits formed in collision volcano-plutonic structures. The studied objects (Gumeshevskoye, Mikheevskoye and Tominskoye) are related to two different types of Uralian porphyry copper ores. Micheevskoye and Tominskoye deposits correspond to Mo-Au-Cu geochemical ore type. Gumeshevskoye deposit corresponds to Cu-Au geochemical ore type and formed under island-arc geodynamic conditions. Deposits of such type are similar to well known North-American objects Morency, Santa-Rita and others, but correspond to magmatism of island-arc type. There is no doubt in the industrial value of these island-arc type deposits, especially their weathered parts. Finally, a new visible gold occurrence associated with Cu-porphyry deposits in plagiogranite-diorite massif core close to Sabanovka VHMS deposits have been discovered by the IMIN team.
Comparison between the European and the Russian mining and environmental legislation in 7 points (EU: European Union RF: Russian Federation) 1) EU: Majority of legislative acts are the acts of direct force. RF: Many laws and legislative acts contain references to other regulations. 2) EU: A big variety of legislative, administrative and technical tools (e.g. licensing, environmental audit, public supervision, environmental impact assessment, and environmental certification). RF: New methods and tools are being introduced, but the mechanisms of their implementation are not well developed so far. 3) EU: A well-developed system of economic stimulation measures (tax privileges, subsidies, etc.) RF: Measures of economic stimulation are insufficient in general and are often not properly implemented. 4) EU: “Non-regulatory” instruments such as “voluntary initiatives” develop in the sphere of environment protection. RF: There are some steps taken by large mining companies and public organizations, but they are very few yet. 5) EU: Integration of policies (incorporation of environmental requirements into other spheres of legislative regulation). RF: Different branches of legislation often lack coordination and interconnection. Environmental requirements should be introduced into civil, administrative, financial and other legislative acts. 6) EU: Dissemination of information (“name, fame and shame” strategy, exchange of information between experts and authorities, communicating information to public). RF: Dissemination of information has rather irregular character and lacks a sound legislative basis. 7) EU: Coordination of activities of public authorities, enterprises and organizations (both inside the countries and between them). RF: Few examples (mostly on international level or on the level of public organizations).
It has been decided that the coordinate system used as reference for GIS work packages is the geographic latitude/longitude (degree, minute, second) WGS84 datum. The database management system is Oracle 8i, and the database interface is developed through a web interface. The GIS tool is ArcView (v. 3.7). For Web applications, the technology has been chosen by IMIN. For each of the thematic data domains to be developed in the frame of the MinUrals project, the main objects have been listed: Vectorial geological map (1:1.000,000 & 1:200,000) Mineral occurrence geophysics Geochemistry (soil/sediment) (1:200,000 & 1:50,000) Drill hole Outcrop 1:50,000 Industrial installation (1:200,000 & 1:50,000) Topography 1:200,000 Environmental Monitoring
Inventory of pollution sources and catalogue of potentially reactive sulphide waste dumps was drafted on schedule (Table 9). Three main sites were investigated, Karabash, with a large Cu smelter, waste dumps and abandoned mines and Sibay and Uchaly with beneficiation mills, waste dumps and abandoned and active mine workings. Karabash was described in 1992 by the United Nations Environment Programme as one of the most polluted towns in the world. The waste dumps and tailings cover an area of more than 250,000 m2 in Karabash, 5 million m2 in the Uchaly mining district and 7 million m2 in Sibay. Details of all the sites and an inventory of pollution sources and waste dumps can be found at: http://www.nhm.ac.uk/mineralogy/minurals/envassess.htm
From the general architecture of the database six basic sections are implemented:COMMON-REFERENCES - the general purpose lexicons used in other sections of a database (lists of mineral kinds and chemical elements; qualifiers of rocks, ores, stratigraphics divisions, etc.); OCCURRENCE - the basic section of a database intended for accumulation and storage of the information on objects of researches, mountain developments, geological routes, results of field supervision, samples of rocks and ores; LABORATORY - data on used methods of analytical measurements with the characteristic of laboratories and the equipment used in them and techniques. Results of analytical measurements of field samples; GMAP the data on structure GIS with the description of all kinds (GIS objects and dynamic from a database) layers of maps of various scale, rules of their display, interaction and generalization;LIBRARY electronic library for accumulation of the bibliographic data under scientific publications and industrial reports; TOOLS the auxiliary lexicons used for construction of the user interface of access to databases. The database has been developed in two formats. Microsoft Access database was used for the initial development of the general architecture and the detailed elaboration of database structure. Besides, in this format the database was used for the accumulation of data in the local computer networks of the partners (Bashkirgeologia, Ufimian Scientific Centre of RAS), and on portable computers carried out for field works. The database has also been developed under Oracle 8i on a server at the Institute of Mineralogy, for the integration of all data in the frame of the project, and to provide an access to these data through Internet. Today, the following data are already stored in the database: 666 descriptions of deposits and mineralized occurrences; 1,564 drill holes, with the description of core and analytical data (13,905 cross-sections); 1,273 environmental samples of air, water, water part sample, solid phase, flora and fauna; 19,092 results of analytical measurements of samples, including: 6,501 spectral analyses; 10,231 chemical analyses of ores; 2,033 silicate analyses of rocks; 327 - atomic-absorption analyses of ecological environmental samples. Data for geological and environmental studies are mostly concentrated in the areas of Uchaly, Molodezhnoe, and Sibay deposits and in the Karabash area. All these data are integrated in a GIS and represent a complete set of layers for the Chelyabinsk district and for specific sites (Figure 17; Figure 18; Figure 19). Along with the static layers generated as GIS objects (the topography, geology - geological map of Chelyabinsk district at scale 1:500,000 and 1:1,500,000 and geological map of Sibay at scale 1:200,000 etc.), dynamic layers are created from the database, dynamically included by the users through the web interface (deposits and occurrences, drill-holes, samples, etc.). The development of the web interface has been realised with the AspMap server module developed by VDS Technologies.
The final report presents the results of the project over the 3 years (Sept. 2000 - Aug. 2003), following the presentation rules of the Commission. It includes: Summary, Consolidated scientific report, Management report, Individual partner reports The results of the project are and will be very useful for the mining companies working in this area. The exploration companies are now armed with updated or new prospect guidelines and tools for ranking their anomalies. Moreover, a new mineralized ore body has already been discovered. Following the results of the environmental studies, recommendations can be made for limiting human exposure to potentially toxic elements and for minimising the future impacts of mining-related activities on environmentally sensitive zones. The results of the work on legislation and the recommendations have been submitted to the President. The improvement of the present legislation, regulating activities of mining and metallurgical enterprises on environment protection, will require new laws, legislative acts and amendments of existing ones.
Monitoring effects of pollutants on sensitive zones has been undertaken using key terrestrial and aquatic organisms, which provide sensitive environmental indicators. In the terrestrial environment, lichen species diversity and frequency were studied along a transect SW and NE from the Karabash smelter (see figure). Lichens are sensitive bioindicators of air quality and are generally widely distributed on bark, rocks and soil. They are especially sensitive to SO2 air pollution, with high levels resulting in low species diversity and a low cover. This was accompanied by studies of metals in leaf litter and cellulose decomposition and an audit of flowering and non-flowering plants. In the aquatic environment, species diversity of chironomid midge larvae have been studied, both living and preserved in lake sediment cores. Chironomid midges are sensitive indicators of environmental change. The heads of their aquatic larvae are abundant and well-preserved in lake sediments which makes them amenable to palaeoenvironmental studies. Short sediment cores were taken from a transect of lakes northeast and south-west of the Karabash smelter. Present-day taxon diversity in all the lakes sampled was relatively high and none of the lakes appear to have been seriously impacted by environmental change recorded as increase in concentrations of heavy metals. The most important environmental driver is trophic change, and in most lakes nutrient levels appear to be lower now than they were in the past, probably reflecting a decline in local agriculture. Three lakes appear to have become more eutrophic probably as a result of nutrient inputs from adjacent dachas and holiday camps. From lead isotope data, a signature from the Karabash smelter has been identified in the top 1 cm sediment samples of nearly all the lakes examined, but this signature is absent from many of the bottom samples. However, there is no indication of a serious impact from the smelter on the chironomid fauna of any of the lakes. The lakes are naturally buffered to the effects of acid rain and runoff, which has caused a serious impact on chironomid faunas in the Kola Peninsula (Ilyashuk and Ilyashuk, 2001). The chironomid fauna in a few of the lakes appears to be responding to increased cadmium levels, but these lakes are remote from Karabash and closer to Miass so the source of this metal is unlikely to be the Karabash smelter. Heavy metals are present in the upper sediments of the lakes near Karabash but do not appear to have had a major impact on the chironomid fauna. However, in the two lakes in which down-core analyses were made, a response to a decrease in Cd levels following temporary shutdown of the smelter between 1998-1997 is apparent. This suggests that although heavy metals may be largely biologically unavailable while the lakes remain relatively alkaline, they are having a small influence on the chironomid fauna.
Deposit models (D6) VHMS The Black smoker model have been proved for the Uralian VHMS deposits. This model includes the history of vent chimney growth from white and grey smokers to black smokers at the stage of heating and again to grey and white smokers at the later stage of cooling and sea floor destruction. The new model of sea floor alteration for clastic sulphides has been suggested. This new model explains the polymetallic composition of most sea-floor altered banded sulphide bodies in comparison to hydrothermal pyrite-rich sulphide mound cores and pyrite sulphide breccia. PGE Some mineral associations in many PGE deposits have the features of low-temperature formation at high oxidation conditions. An alternative model of magmatic origin is also proposed. gold The continental collision led to the transformation of massive sulphide deposits with the extraction of gold from sulfides by metamorphic fluids, which formed gold-rich quartz vein types. This process existed in Degtyarsk-Karabash zone. The halmyrolysis model of gold enrichment in clastic sulphide deposits has been considered, too. Cu-Porphyry The other idea about the degree of genetic unity between ore-metasomatic haloes of hypabyssal porphyry copper deposits and subvolcanic Au-Ag-polymetallic deposits have been considered on the example of the neighbouring meso-abyssal Tominsk copper porphyry and subvolcanic Bereznyakovsky Au-porphyry deposit. The original paragonite-containing metasomatites with homogeneous K-Na-wite mica were revealed and described by us for the first time for the copper porphyry system. This suggests the genetic unity of considered ore-metasomatic haloes of different types in the single vertically extended copper porphyry column. New data to improve the knowledge of deposit genesis (D7). The osmium content increase and the 187Os/188Os isotope composition decrease in the ore facial range of the Alexandrinka and Dergamish VHMS deposits: stockwork zone - sulphide chimneys - coarse-clastic ore - fine-clastic ore - submarine alteration zone on the hanging wall. This reflects the degrees of hydrothermal fluid - seawater mixing during the hydrothermal ore-forming process.The Re and Os isotope data for Dergamish define a best-fit line corresponding to a Late Devonian age of 366±2 Ma. The Re-Os isotope signature has been perturbed in the Alexandrinka hydrothermal system, which could result in late addition of rhenium. The preservation of unradiogenic Os isotopic ratios in some of the Ivanovka samples and the near chondritic initial Os isotopic composition obtained for the Dergamish samples indicates that most of the Os in the massive sulphides was ultimately derived from the mantle. The corresponding tectonic setting equates to an area with submarine high-level mantle rocks. The S and C isotope composition in ore facies of the Yaman-Kasy, Alexandrinka, Sibay, Saphyanovka VHMS ore bodies has been studied. The data suggest the influence of sea-floor alteration on sulphur isotope fractionation. The organic matter, extracted both from hydrothermal sedimentary colloform and biomorphic sulphides has light composition of carbon, like to those which where discovered in modern near vent fauna assemblages. On the basis of detailed studies of fluid inclusions the formation conditions of different ore facies and associated carbonate rocks of Au-Ag-Cu-Zn Alexandrinkoe deposit were reconstructed. The approximate range of homogenization-temperature and salinity decrease from stockwork (300°C) to vent chimneys (110-230ºC) to the seafloor altered sphalerite-rich sulphide layers (110-152ºC, NaCl 3.5-3.7 wt.% NaCl). The increase of seawater influence in this range is suggested. The model of genetic unity of meso-abyssal (Tominskoe) and subvolcanic (Bereznyakovskoe) has been proved by mineralogical, isotopic d18? = 9.5 – 12.8‰, dD and PT data. The model of VHMS-bearing sedimentary fields has been improved by research of REE–geochemistry of ferruginous products of halmyrolysis of sulphides and hyaloclastite mixed with carbonates. The model of sea-floor leaching processes may be useful for explanation of REE-depletion and special spectra styles peculiar to siliceous-ferruginous deposits in addition to model of sorption processes considered in previous. Improved metallogenic models for the South Urals deposits. Guide for mineral exploration (D8). A common metallogenic model of the South Urals evolution, from continental rifts, oceanic stage, island arcs to collision events, has been developed. The understanding of each stage of mineral deposit specialization has been improved mostly due to the modern methods of analysis: microprobe mineralogical research, Re-Os isotopic research, LA-ICP-MS analysis of ore minerals.
Polluted sites have been ranked according to a wide range of factors, including past, present and future scope of contamination, spatial aspects, proximity to local populations/sensitive ecological zones and climatic factors. Karabash is considered to be of most immediate concern due to the likely effects on human health of smelter emissions (D23). The second priority is the contamination of surface waters by acid rock drainage and contaminated sediments from the large tailings dumps in Karabash. A proportion of the tailings are contained in constructed tailings dams south of the smelter. However, between 1925 and 1958 tailings were pumped into the Sak-Elga valley, through which the Sak-Elga river flows into the Argazi water reserve. The river valley contains an average thickness of 1.5 m of tailings-derived material over an area of around 1,800,000 m2. High levels of Mn and other metals are being discharged into the Argazi water reserve, which feeds the regionally important Miass River (Herrington et al., submitted). The bottom of the Argazi water reserve contains up to 1.5 m of tailings-derived materials with high levels of potentially toxic elements (e.g. > 500 ppm As), posing a long-term threat to aquatic organisms including fish. In the Sibay and the Uchaly mining districts, atmospheric emissions are produced from beneficiation mills and from wind blown dusts from the wastes and tailings. Compared with Karabash, ambient atmospheric particulate (TSP) in the town contains a much lower level of potentially toxic elements (Williamson et al., in pressa). Additionally, the metals are mainly in the form of sulphides which pose a lesser health risk than the more soluble oxides and sulphates which dominate Karabash smelter emissions. The main environmental concern in Uchaly and Sibay is from surface water contamination from acid mine drainage and leachates from waste dumps and tailings. Both sites are located in areas of relatively low precipitation and the volumes of contaminated waters are therefore small. Current environmental management systems in Uchaly were found to be effective, with much of the waters used in the process being recycled, 85% according to the mine management (Williamson et al., in pressc). In the Sibay area, country rocks contain limestones and therefore have a high acid neutralisation potential. Discharges of metals into the environment are therefore relatively low compared with Karabash. The long term environmental outlook at both sites is judged to be of more concern than immediate impacts. Mine abandonment and cessation of pumping of underground workings is likely to cause a rebound of the water table and contamination of ground and possibly surface waters. There is also a long term environmental risk from the large volumes of wastes and tailings which have a high acid forming potential and contain high levels of toxic elements (see D29). Studies of the mineral residence of harmful components of mine waste is being carried out by the IMIN team through the analysis of leachates from wastes and tailings and using standard laboratory leaching tests.
Sampling chart and analytical recommendations for environmental control have been designed taking into account the specific environmental and socio-economic needs of the region. Sampling for environmental assessment needs to be low cost, discrete (to avoid tampering), and the results comparable with Russian and international standards. A combination of instrumental and bio-monitoring methodologies will be necessary as instrumental monitoring is usually the only affective way of acquiring quantitative data for comparison with standards and while the low cost bio-monitoring methods will be used on a wide geographic and temporal scale. Recommendations for environmental control are summarised for Karabash in Table 10. The priority is prevention of exposure of the Karabash population to smelter emissions. The closing down of the smelter was attempted in October 1991, however it was re-opened in March 1997 due to the economic hardship this caused. The installation of dust and SO2 controls would be ideal but this may be prohibitively expensive. Thorough costs benefit analysis would need to be undertaken and a source of finance found. The lowest cost solution maybe to move the townspeople to a location outside the zone affected by the plume of the smelter about 30km according to the present results, and to provide a bus service for workers. Most dwellings are of simple wooden construction and could easily be relocated. The immediate priority for the prevention of further surface water contamination is to treat the leachates from the tailings. A liming station and settling pond need to be installed near to where the Sak Elga stream enters the Argazi water reserve, see: http://www.nhm.ac.uk/mineralogy/minurals/karabashmap.htm Tailings within the Sak Elga valley need to be removed and placed into a contained and managed tailing pond, from where the leachates can be channelled for treatment and in which the tailings can be covered in a suitable impermeable barrier and vegetated according to modern tailings management methodologies.
b. Model for pollutant transfer, model for existing waste dump behaviour (deliverable D23)The model for pollutant transfer has been developed through the characterisation of pollution vectors. The main vectors are atmospheric transfer of airborne particulates and gaseous pollutants (SO2 being of prime concern) and the discharge of contaminated waters and suspended material into the environment. The priority for assessment was the characterisation of atmospheric pollutants from the Karabash Cu smelter, as from preliminary studies in October 2000 this was considered to be having an immediate impact on human health (Udachin et al., 2003). Houses in Karabash town may be blanketed in the plume from the smelter for many hours at any one time. Within this plume, SO2 levels up to 20,000 ;g/m3 (spot measurement) were recorded, which compares with a World Health Organisation recommended maximum of 500 µg/m3 (10 minute mean concentration). Airborne total suspended particulates (TSP) were collected at sites up- and downwind of the smelter and large waste and tailings dumps (Oct. 2000 & July 2001, Williamson et al., in pressa). Mass of TSP was found to vary between 8 and 156 µg/m3, well below the Russian maximum permitted level for TSP of 500 µg/m3 (24 hr average), however the particulate was found to be 100% respirable. The main element of human health/environmental concern, above Russian maximum permitted levels (1 µg/m3, average over any time period), was Pb, which was measured at 16-30 µg/m3 in downwind samples. The mineralogy of the TSP was assessed using a newly developed PSD-Microsource® XRD technique and was found to consist of a complex mixture of anglesite (PbSO4), Zn2SnO4 and poorly ordered Zn sulphates. From experimental and theoretical considerations, a high proportion of contained Pb, Zn, Cd and As contained in this material is considered to be in a readily bioavailable form. The levels and types of airborne particulate in ambient air in Karabash are considered to present a major risk to human health. Pollutant transfer from the discharge of contaminated waters and suspended material was studied through a programme of seasonal water and sediment sampling. Improved sampling protocols were agreed between the IMIN and NHM teams for the 2001-2002-field season and the analytical programme was carried out on schedule. The studies identified significant contamination of surface waters in the area around Karabash. The model for waste dump behaviour has been dealt with through the mineralogical and geochemical analysis of wastes at the NHM and leaching tests and the analysis of natural leachates at IMIN.
The study of VHMS deposits was based on the new principles of ore-facies analysis. The different ore facies were mapped and sampled in the open pits of Sybay, Yaman-Kasy, Molodeznoe, Alexandrinskoe, Barsuchiy Log , Jusa, Balta-tau, Tash-Tau VHMS deposits open pit and Talgan, Mauk underground shaft. The mineralogy and trace elements geochemistry for stockwork veins vent chimneys, hydrothermal-biomorphic, clastic and halmyrolitic ore facies have been studied. Each ore facies of the Urals VHMS deposits are characterised by specific mineralogical composition. Hydrothermal ore facies contain diverse tellurides and native gold. Native gold, electrum and rare hessite assemblages are common for ggrey smokersh vent chimneys from Alexandrinka deposits. Numerous Pb, Bi, Hg, Au, Ag, Co tellurides, telluroarsenides and tellurosulpoarsenides, native tellurium, tellurium oxide native gold have been identified in Yaman-Kasy black smokers vent chimneys. Electrum and Ag-rich sulphotellurides, sulphides, sulphosalts of these metals are more common for the seafloor altered clastic sulphides from VHMS deposits of island arcs (Utrennee, Zvezdnoe, Uvaryazh, Balta-Tau). There is a high diversity of Co-Ni arsenides and suphoarsenides. Traces of Pd (up to 0.5%) have been found by microprobe analysis in coloradoite and pentlandite. Minerals of each ore facies and microfacies yield signatures of trace elements evolution during hydrothermal, hydrothermal sedimentary, seafloor alteration and metamorphic processes. The study has shown a systematic distribution pattern within the chimneys for two groups of trace elements. Group 1 elements (Mn, As, Tl, Pb, Ag and Au) are enriched in colloform pyrite in the outer-most section of the chinmey wall. This enrichment probably results from rapid precipitation of colloform pyrite under low temperature conditions. Pyrite euhedra, which result from the recrystallisation of colloform pyrite toward the inner wall, are depleted in the Group 1 elements. Group 2 elements (Bi, Ag and Au) are enriched in chalcopyrite along the boundary between the chalcopyrite inner wall and the sphalerite filled central conduit, where Bi, Ag, Au, Pb tellurides have been precipitated in a zone of strong temperature gradients. The main zone of chalcopyrite within the central inner wall is depleted in Group 2 elements, probably due to the high temperature of formation, which is unsuitable for telluride precipitation. Generally, trace element concentrations of chimneys increase with the decrease in chalcopyrite content from pyrite-chalcopyrite- to marcasite-chalcopyrite-sphalerite- to marcasite-quartz-rich chimneys, due to the decrease in temperature and increase in Eh of the black smoker and seawater fluids mixtures. Trace elements diagenetic partition has been studied in sulphide sandstones. Diagenetic and mesogenetic subhedral pyrite in comparison to hydrothermal-sedimentary colloform pyrite is depleted in Tl, Mn, Au, Ag and is sometime enriched in Co. The free visible native gold and electrum grains formed clastic sulphides due to this process of diagenetic recrystallisation. Pseudomorphous chalcopyrite which was formed after pyrite was enriched by Mn and As in comparison with hydrothermal chalcopyrite incrustation. Hematite-rich gossany products of seafloor oxidation of clastic sulphides were depleted of chalcophile trace element. They contain only new elements as like Ni, V , Mn and Ba. VHMS deposits of the South Urals generally show a continuum in degradation and reworking ranging from pristine steep-sided hydrothermal sulphide mounds to deposits dominated by layered strata of clastic sulphides. Four different deposits with varying degrees have been ranked in order of increased reworking: Yaman-Kasy (N.Sybay, Ozernoe, Komsomolskoe) Molodezhnoe (Uchaly, Chebachye, Yubileynoe, Blyava) Alexandrinskoe (Talgan, Barsuchiy Log, XIX parts fezda) Balta-Tau (Jusa, Babarik, Utrennee, Zvezdnoe, Uvaryazh). The influence of sulphide mound destruction and sea-floor alteration on the gold-silver-tellurium mineral assemblages was investigated. The mineral assemblages changed from Au, Ag, Hg, Co, Bi tellurides to Pb, Ag, Cu-sulphide+gold , then to Ag sulphosalts + electrum and kustelites wich were enriched by Hg, and Bi. The gold standard decreases from 930 in pyrite breccia to 450 and less in polymetallic barite-rich low temperature sea floor altered associations. We suggest that the mineralogy and siting of native gold, silver and tellurium are a consequence of cooling and/or oxidation of hydrothermal fluids and also of seafloor alteration of primary sulfides and tellurides. A geochemical classification of VHMS deposits using the degree of secondary enrichment of Ag and leaching of Te seems possible.
New data about metallogeny and geodynamic setting of the VHMS-bearing Main Urals FaultBasalt in previous research was considered as a part of oceanic rifts. However, new geological and petrologic data show the complexity of this district. The tectonic nature of intercalated slices of oceanic and island arc crust has been proved. High-Cr, low-Al, and low-Ti compositions of spinals included in sulphides and the surrounding rocks, and the major-element composition of melt inclusions in spinals denotes a clear island-arc or near-arc affinity. The discovery of boninite-rich units allows anticipating the development of new geodynamic models for the Main Urals Fault. Kroseven and IMIN provided the first description of volcanic facies and mineralogy for the ultramafic VHMS bearing areas of Ishkinino, Dergamish and Ivanovka. Definition of Atlantic ore of Cyprus type have being fruitful discussed for these deposits. Pb isotopes The isotopic composition of lead from a total of 53 samples of galena from footwall stockwork zones of 18 VHMS deposits range between 17.437 and 18.427 for 206Pb/204Pb; 15.484 and 15.630 for 207Pb/204Pb and 37.201 V 38.027 for 208/204Pb (BRGM analyses). The back arc (Sybay) and fore arc (Bakr-tau, Oktybriskoe) and arci (Balt-Tau and Gay) signatures of some VHMS deposits has been shown. Sedimentological studies Sedimentological evidence for an extensional nature of different VHMS-bearing zones has been considered. The presence of xeno-lavoclastite sediments with numerous xenoclasts of plagiogranites and shallow volcanic, volcano-sedimentary host rocks and sulphide ores as a typical signature of local inter-arcs extensional zone has been established. The volume of sedimentary to volcanic units increases from Western to Eastern part of the South Urals in correlation with the degree of destruction and halmyrolysis of VHMS deposits. Trace elements signature New metallogenic approach on the basis of ore trace elements analysis for other South Urals VHMS deposits has been considered. The W-Mo signature of VHMS deposits of East Magnitogorsk island arc (Alexandrinskoe, Babaryk VHMS deposits) suggests the presence of granite basement in the East-Magnitogorsk island arc. Co-Bi-Te specialisation of the western part of the Southern Urals (Sacmara marginal sea and Main Urals Fault) basin has been explained by the influence of mantle derived oceanic mafic-ultramafic crust. Platinum Group Elements (PGE) deposits New idea about the metallogeny of PGE-deposits in Urals Platiniferous Belt has been suggested (by BRGM, IGG, and IMIN). In this belt, the magmatic rocks have a clear petrologic relationship with gabbro and ultramafic xenolites in basalt of island arcs, as well as with rocks of gabbro-ultrabasite complexes of the Pacific Ocean rim (S. Alaska, California, Koryakia and others). The main massifs are fully situated among geological complexes, which had been formed in above-subduction environments. Copper porphyries. The western Cu-porphyry ore-bearing Na plagio-granitoid complexes give way to the eastern K-Na complexes. In agreement with such zoning, the sericite-quartz and paragonite-quartz alteration haloes are changed by potassic alteration at deposits of the Turgai Zone along with enrichment of ore in Mo. The Cu/Mo ratio in ore decreases from 250-600 in deposits of the Tagil-Magnitogorsk Zone to 150-400 in deposits of the East Volcanic Zone and 100-250 in deposits of the Turgai Zone. The highest Au grade is fixed in deposits of the subvolcanic level. Only porphyry copper deposits of the Turgai Zone fit the classic marginal continental ore zones of the Andean and Cordillerian types.
Modelling of the environmental impacts was undertaken using results from the broad range of environmental assessment methodologies employed. Levels of Cd, Cu, Zn and As in beetroot, carrot, potato, cabbage and onion often greatly exceed Russian recommended limits for vegetables. Except in potato, levels of Pb greatly exceed EU proposed limits (III/5125/95 Rev.3). The results from the monitoring of airborne contaminants, soils and foodstuffs have been input into the IEUBK (2002), Integrated Exposure Uptake Biokinetic Model for Lead in Children. No data was available for mothers blood Pb levels at childbirth and therefore with an input value of zero the results of the model are an underestimate of blood Pb levels in children. Assuming an outdoor Pb level of 20 �Ýg/m3 (indoor Pb levels 10% of outdoor levels), an average of 0.1 �Ýg/g Pb in foodstuffs, 1.2 �Ýg/L Pb in water (the average for well waters) and 80 �Ýg/g Pb in soils, the model indicated that 84% of children may have blood Pb levels above the 10 �Ýg/dL recommended maximum. Modelling of impacts on terrestrial and aquatic organisms was covered under D25. Recommended sampling strategy for monitoring in Karabash Air qualitySampling Methods: Instrumental air filter sampling, Lichen sampling, Snow Sampling, Soil sampling Sampling frequency: Monthly or seasonally, A continuous analyser such as a TEOM device could be installed in Karabash to monitor PM10 levels. Monthly collections from air filter apparatus will be necessary to monitor levels of lead. Regional extent of fallout from the smelter should be monitored using lichens during the summer period and snows during winter. The long term effects of atmospheric deposition on soil requires long term monitoring of soil in natural and inhabited environments. Surface waters Sampling Methods: Water and sediment sampling Sampling frequency: Monthly or seasonally to monitor emissions and effectiveness of remediation measures Ground waters Sampling Methods: Installation of piezometers at key localities Sampling frequency: Monthly, particularly following cessation of pumping of mine workings and natural flooding events. Local foodstuffs Sampling Methods: Locally produced vegetables, fish, meat, milk Sampling frequency: During main harvests or monthly for continuously supplied produce
Geochemical model for toxic component release has been developed through the characterisation of pollutant emissions and pollution vectors (see D23). Atmospheric airborne particulate (TSP), stack dusts from the smelter and dusts from snows have been characterised in the town of Karabash, including sequential extraction studies of the smelter dusts to assess the proportion of bioavailable metals (Williamson et al., in pressa). TSP has also been characterised in Sibay and Uchaly (see D24). Data is also now available for 48 road dusts collected from Karabash, Uchaly, Sibay and Miass, which will form the basis for a future publication. The road dusts in Karabash contained up to 287 ppm As, 13 Cd, 3450 Cr, 21000 Cu, 1200 Pb and 13500 ppm Zn, and therefore constitute a major potential source of metal-bearing airborne particulate which may be respirable, contaminate soils and adversely affect human health. The release of toxic components into surface waters has been described under D24.
Spatial patterns of seasonal air pollution and fallout were studied for the summer period by the NHM team using lichen transplants. This procedure involved the relocation of naturally growing lichens from a site 30 km from the smelter (�background site�) to 10 transplant monitoring stations along a ca. 60 km transect centred on Karabash. Transplant material was collected after 2 and 3 month periods (September and October 2001) and was analysed by ICP-AES and ICP-MS to investigate element trends and biogeochemical signatures (Purvis et al., in press). 25 elements showed systematic decreases away from the smelter, suggesting this as their major source. 206Pb/207Pb isotope ratios are similar to those associated with airborne particles in Europe and Russia. An outlier near Kyshtym to the north of Karabash had a lower ratio indicating a source with higher 235U/238U. The method was found to be discrete and cost effective and able to detect short-term pollution episodes. The studies of lichen transplants have been supplemented with those of fungi, soils and pine needles over a similar transect (Spiro et al., 2003). The sources of Pb have been assessed using Pb isotopes in a range of environmental media, and compared with smelter stack dusts (Udachin et al., in press). The mapping of air pollution fallout in the winter period was carried out by the IMIN team using snow core samples and by sulphur isotope analysis of snow melt waters by the NHM team.
Modelling programme to predict impact of future mining related development is based on three main considerations: geology, climate and hydrogeology. The potential of an area for natural attenuation is paramount when considering future mining development as this may restrict pollutant dispersion and reduces the need for costly remediation schemes. The key factor in determining the level of natural attenuation is the acid neutralisation potential (ANP) of local country rocks, which is controlled by the geology. A high ANP in waste rocks will increase the pH of leachates and will limit the migration of potentially toxic metals into the environment. The pH of any acid rock drainage (ARD) waters will be rapidly increased when the ARD mixes with unimpacted high pH stream waters and the mixture then flows through country rocks with a high ANP. With the construction of a settling pond, a high proportion of metals will precipitate out and be deposited. This is the situation in Sibay where in April 2002 leachates from the waste dumps were found to have a pH of 3.3 (12 ppm Cu), they mixed with unimpacted waters with a pH of 7.4 (0.004 ppm Cu) and following the settling pond and beneficiation mill (i.e. as discharge from the mining area) they had a pH of 6.7 (0.015 ppm Cu). The main problem with the discharge waters is high levels of Mn which it is suggested may be mitigated at relatively low cost with the installation of a second settling pond and possibly with the aid of liming. Climate is an important factor in predicting impacts from mining, as levels of precipitation will affect the volumes of leachates produced from the waste dumps and levels of dilution from unimpacted waters. Temperature will have an affect on sulphide oxidation rates in the dumps and therefore the liberation of toxic components. The influence of these factors has been observed in a general way from a simple comparison of surface water environments in Karabash vs Sibay and Uchaly, Karabash lying within the South Taiga climatic zone, Sibay in the Forest-Steppe zone and Uchaly on the border between the two zones. The influence of hydrogeology could not be assessed under the MinUrals project as the necessary maps and data were not available from the mining companies.
A portable mercury analyser (HgMonitor3000)was selected and purchased. Comparison measurements at selected sites were conducted using a portable Russian mercury analyser AGP-1 manufactured by Uralgeovizpribor (Russia). In view of the strong dependence on weather conditions and the small measurement distances required, particularly to detect steeply dipping lode-gold deposits, it is suggested here that the mapping of soil gas Hg0 anomalies is not an economic primary method to locate buried VMS or lode-gold deposits. However, the successful application of this method at anomalous areas defined first by geophysical methods, mapping of alteration zones or geochemical halos in soil could provide a useful argument for drilling. In context with the relatively low soil gas Hg0 concentrations measured at the sites of buried ore deposits, the use of a mercury analyser applying the gold amalgamation technique like the AGP-1 is recommended in such exploration work. The HgMonitor3000 system is considered to be particularly useful for the rapid localization of mercury contaminated sites as exemplified at several former amalgamation installations in the southern Urals. In view of the measured high concentrations of Hg0 in soil gas at these sites and the small depth of the mercury reservoirs compared to deeply buried ore bodies, the investigation of mercury contaminated sites by this method is considered to be promising during all seasons without ground frost.
This was tackled through the development of lichen bio-monitoring methodologies (See D26, Williamson et al., in pressb), and the sampling of natural environmental media including fungi, garden vegetables, snows, pine needles, road dusts (D28) and chironomids (see D25). The analysis of these media can be carried out using standard techniques available in a number of institutions in the Urals. A discrete and low technology sticky pad method for monitoring nuisance dusts was also used.

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