The results of U–Pb age determination, Nd–Sr–Pb isotope systematics and geochemical study of quartz diorites associated with ore-bearing (Cu–Pd–Au–Ag) gabbro of the Volkovskiy massif localized within the Ural Platinum Belt, at its eastern border with Silurian-Devonian volcanogenic complexes of the Tagil megazone are presented. The age of quartz diorites by U–Pb (TIMS) age determination is 429±9 mln years, MSWD = 0.009. Sr–Nd–Pb isotope characteristics (ƐNd(T) = +5.5 ÷ +6.7; (87Sr/86Sr)t= 0.70382−0.70392;206Pb/204Pb = 18.38−18.57;207Pb/204Pb = 15.56−15.58;208Pb/204Pb = 38.14−38.30) indicate a juvenile source with a model age of 570−760 mln years. The obtained data do not go beyond the values typical for basalts of enzymatic island arcs. The geochemical features of the granitoids of the Volkovskiy massif (low REE concentration, differentiation of their spectrum (La/Yb = 8−14) with weak positive Eu-anomaly (Eu/Eu* = 0.9−1.4)) are consistent with the characteristics of melts obtained in water melting experiments for mafic rocks in equilibrium with amphibole-pyroxene restite. The anomalous strontium concentration (more than 1000 g/t) in quartz diorites is due to the high content of this element in the source. Such source could be the earliest rocks of the Ural Platinum Belt – olivine gabbro and surrounding metamorphic rocks. The same age of quartz diorites of the Volkovskiy massif and monzonitoids of the Kushvinskiy massif allows us to consider these rocks as a result of the mantle and crust melting converged in time at the final stage of the Tagil island-arc system formation.

This electronic document sets out an approach to assessing the damage value in determining the risks of information security in complex systems concerning the distribution of separate elements of business processes within the software/hardware system complexes and the estimation of their cost.

The paper is concerned with an approach to constructing mechanisms for managing the security of a complex system in conditions where the local risk functions of independent elements of the system are random. It proposed to use linear or quadratic functionals of a particular type as a framework for ordering local risks.

Research subject. The mineral compositions of titanomagnetitic (apatite, titanomagnetite) and copper-titanomagnetitic (bornite, chalcopyrite, apatite, titanomagnetite) ores of the Volkovskoe Cu-Fe-Ti-V deposit (Middle Urals, Russia).Methods. The research was carried out using a Jeol JSM-6390LV scanning electron microscope and X-ray spectral microanalyzers JXA-5 (Jeol) at the Geoanalitik Collective Use Center of the IGG UB RAS. Results and conclusions.Native gold (with ≤ 0.3 wt % Pd, 0.2–0.4 wt % Cu; fneness 800–914 ‰), tellurides of Pd, Au and Ag (merenskyite, keithconnite, sylvanite, hessite) and Pt arsenide (sperrylite) were found in the copper-titanomagnetitic ores. For the frst time, two generations of native gold (fneness 1000 and 850–860 ‰) and palladium telluride (keithconnite Pd3-xTe) were detected in titanomagnetitic ores. The sequence of ore mineral formation and the features of their genesis were revealed. Native gold (fneness 1000‰) in the form of microinclusions in titanomagnetite was attributed to the magmatic stage. Noble metal minerals, intergrown with copper sulfdes (bornite, chalcopyrite, digenite) and associated with late hydroxyl-bearing minerals (amphibole, epidote, chlorite), are superimposed in relation to the magmatic minerals (pyroxene, plagioclase, hornblende, apatite, titanomagnetite, ilmenite, etc.) of these ores. Merenskyite, sperrylite, high fneness gold (800–914 ‰), as well as carrolite, cobaltite, copper-cobalt telluride and bismuth tellurium-selenide kawazulite Вi2Te2Se are syngenetic with copper sulfdes. The Au-Ag tellurides were deposited later than these minerals. It is shown that the high fugacity of tellurium, which binds Pd, Au, and Ag into tellurides, prevents the occurrence of native gold containing high concentrations of palladium and silver.

The paper is concerned with a general model of complex computer network, within which a risk manager exercises efficient management of risks of a complex system through distribution of available resource among its elements (units of computer networks). A tasks of risks management are considered in a context of uncertainty and mutual influence of system elements on each other and methods for solving them are proposed.

This paper considers one of the methods of efficient allocation of limited resources in special-purpose devices (sensors) to monitor complex network unit cybersecurity.

This paper reports chemical, geochronological, and Hf–Nd–Sr isotopic-geochemical data on granite, leucogabbro, and microgabbro porphyrite vein bodies in the gabbro of the Volkovsky massif. It was proved that the vein granite and leucogabbro are genetically related to the leucogabbro–anorthosite–plagiogranite (anorthosite–granite) series of the Urals Platinum Belt. The granite was dated by U-Pb laser ablation inductively coupled plasma mass spectrometric method at 409.0 ± 2.3 Ma. The rock has 87Sr/86Sr(409 Ма) = 0.70358, high εNd(409 Ма) = 6.4–6.5, and εHf(409 Ма) ≥ 10.8. Similar values of 87Sr/86Sr(409 Ма) = 0.70370 and εNd(409 Ма) = 5.9 were obtained for the vein leucogabbro. The isotopic-geochemical data are consistent with existing concept of the formation of the leucogabbro–anorthosite–plagiogranite (anorthosite–granite) series through partial melting of the olivine gabbro. The measured 143Nd/144Nd = 0.512939 value obtained for the microgabbro porphyrite reflects their more radiogenic composition and likely a mantle source. The granite, associated leucogabbro, and microgabbro porphyrite were emplaced at the final magmatic stage in the massif evolution. This event marks the upper age boundary of the Au–Pd mineralization related to the gabbroic rocks. The vein rocks lack any signs of the mineralization. However, it is highly probable that they were sources of energy and fluid for reworking of the earlier olivine gabbro and redeposition of ore components in this rock.

Tetrahedrite-Freibergite group, their mineral associations, intergrowths and chemical composition from Silver-Lead-Zinc epithermal Prognoz deposit have been studied. Possibility of using of fahlores as indicators of ore-forming environments of the deposit was shown.

The article presents new isotope-geochemical data on zircon from gabbronorites of the Volkovsky massif in the Middle Urals. The massif is a complex combination of different rock associations - from ultramafic rocks to syenites and quartz diorites, whose geological and geochronological ratios are not well-defined yet. The most widespread in the massif are gabbroids, which form three blocks - the Central, Western and Southern ones. This massif is associated with: 1) industrial deposit of copper-iron-vanadium ores and 2) gold-palladium mineralization of low sulfide type. Gabbronorites, which form peripheral parts of the gabbro blocks and in some cases form dykes among olivine gabbro, have a dual relationship with mineralization. They are host for copper-iron-vanadium type and postmineral concerning the gold-palladium mineralization localized in ultramafic rocks and olivine gabbro of the Southern block. The comprehensive study of zircon (its morphology, internal structure, U-Pb age, and silicate inclusions) has shown that in gabbronorites of the Volkovsky massif, zircon aged 427.5 ± 5.3 Ma and 428 ± 7 Ma, extracted from two different samples, contains the same set of polymineral inclusions, alien to the hosting rocks. The composition of inclusions (plagioclase ( An21), biotite (f = 0.49-0.56), quartz and apatite) corresponds to gneiss or plagiogranite. However, the zircon, according to its morphology, internal structure and age characteristics is similar to that from metamorphic rocks of the dynamothermal halo of gabbro-ultramafic bodies. This suggests that the zircon in gabbronorites of the Volkovsky massif could be borrowed from the surrounding metamorphic rocks, and therefore, the gabbronorite intrusion occurred when high-temperature metamorphic rocks of the dynamothermal halo had already existed and might have undergone anatexis and retrogressive metamorphism of amphibolite facies. The zircon age (≈427 Ma) limits the lower time limit of the formation of gabbronorite intersecting olivine gabbro of the Volkovsky massif, and may be close to the time of the formation of copper-iron-vanadium and gold-palladium mineralization type controlled by the reaction processes between gabbronorites and olivine gabbro.

The isotopic and geochemical characteristics of PGE mineralization in high-Mg chromitite from the banded dunite–wehrlite–clinopyroxenite complex of the Nurali lherzolite massif, the South Urals, Russia is characterized for the first time. Electron microprobe analysis and LA MC-ICP-MS mass spectrometry are used for studying Cr-spinel and platinum-group minerals (PGM). Two processes synchronously develop in high-Mg chromitite subject to metamorphism: (1) the replacement of Mg–Al-rich Cr-spinel, orthopyroxene, and diopside by chromite, Cr-amphibole, chlorite, and garnet; (2) the formation of a secondary mineral assemblage consisting of finely dispersed ruthenium or Ru-hexaferrum aggregate and silicate–oxide or silicate matter on the location of primary Ru–Os-sulfides of the laurite–erlichmanite solid solution series. Similar variations of Os-isotopic composition in both primary and secondary PGM assemblages are evidence for the high stability of the Os isotope system in PGM and for the possibility of using model 187 Os/ 188 Os ages in geodynamic reconstructions.

40Ar-39Ar, Sm-Nd, U-Pb, and Lu-Hf isotope data are reported on the gabbro of the Volkovsky Massif, the only massif of the Uralian Platinum Belt wherein economic copper-iron-vanadium and high-grade gold-palladium mineralization is present. The massif is made up of gabbro blocks with concentrically zoned structure and diorite intrusions in its core. In the northeast and southwest, the gabbro is cut by syenite of the Kushva Massif. Gabbro blocks mainly consist of the olivine-anorthite gabbro, while labradorite two- pyroxene gabbro intersects both olivine-anorthite gabbro and Ti-magnetite and copper-PGE mineralization developed in them. The study of both gabbro types by Sm-Nd isochron and U-Pb (SHRIMP II) zircon methods with subsequent REE and Lu-Hf isotope analysis of zircon made it possible to date reliably (428 ± 7 Ma (SHRIMP) and 436 ± 21 Ma (Sm-Nd)) postore labradorite gabbro and, correspondingly, the upper age limit of the mineralization of the Volkovsky Massif. Ore-bearing olivine-anorthite gabbro contain four different-age zircon populations: 2682 ± 37–972 ± 18 Ma, 655 ± 15 to 565 ± 9 Ma; 450 ± 12 Ma, and 343 ± 8 Ma. Hf-Nd isotope systematics showed that zircon with an age of 450 ± 12 Ma presumably marks the formation age of the rocks, the older zircon was trapped, while zircon with an age of 343 ± 8 Ma was formed during low-temperature transformation of the rock and sometimes contains excess radiogenic Hf. Proterozoic xenogenic zircon was inherited from diverse rocks of ancient crust, while the oldest grain with an age of 2065 Ma was possibly formed in a deep mantle source. Vendian zircon was presumably also entrapped, and its morphology and geochemistry point to the crystallization from a basaltic melt. The abundance of pre-Paleozoic zircon in the olivine-anorthite gabbro suggests significant contribution of ancient material in their petrogenesis. This material could serve as source of ore components (metals and sulfur) for unique copper-sulfide gold-PGE mineralization of the Volkovsky Massif.

Drill cores from the newly discovered Baronskoe-Kluevsky Pd–Au deposit (Volkovsky massif, Central Urals) have been investigated by reflected-light and electron microscopy, and the ore minerals were analyzed by electron microprobe. The most abundant Platinum-group mineral (PGM) is vysotskite, ideally PdS, characterized by an unusual Pt,Ni-poor composition. Palladium also occurs in kotulskite (PdTe), stillwaterite (Pd8As3), and unknown Pd–As–Te compounds with vincentite-type Pd3(As,Te), stillwaterite-type Pd8(As,Te)3, and Pd7(As,Te)2 stoichiometries. The main carrier of Au is Pd-rich electrum, approaching the composition Au75Ag15Pd10, with minor Fe, Cu, Ni and Pt. The precious minerals are closely associated with minute blebs of chalcopyrite+magnetite disseminated throughout serpentinized olivine-apatite host rock. Paragenetic relationships among the ore minerals define a succession of crystallization events in the order: 1) Cu–Pd sulfides+electrum, 2) replacement by Pd–Te–As and late Pd–As PGM, 3) final replacement by magnetite. The paragenesis is tentatively related with cooling of a fluid phase in the late- to post-magmatic stage.