The article presents data on landscapes, geodynamic regime, and sedimentation at the Cretaceous-Paleogene epoch, which was characterized by planation of most territories on all continents. It is shown that crustal extensional environments have dominated both on platforms and mobile belts (which had nearly simultaneously the Laramide orogenic phase). These conditions caused relief planation (with the development of weathering crusts and products of their rewashing) as well as basaltic volcanism and rifting in platforms and in certain parts of mobile belts. The latter processes were most active within mobile belts and in oceanic areas. Found that in the mobile belts of characterized era where environment stretching has dominated is also evident processes of compression of the crust, which played a secondary role. These processes formed orogens, induced folding and thrusting, and were commonly accompanied by intermediate and acid volcanism. Intermountain molasse and coal-bearing formations simultaneously accumulated in terrestrial environments. The predominance of the aforesaid features, which are typical of crustal compressional settings, provides a basis for identifying orogenic epochs of tectogenesis. In this sense, their antipode - epochs of relief peneplanation - is commonly referred to regime of tectonic quiescence. However, the example of the boundary Cretaceous-Paleogene epoch indicates that the sharp intensification extension and particularly intense - in the mobile continental margins and oceanic areas, allows classifying them as a special category of tectonically active epochs with the dominance of destructive type of tectogenesis. The principal features of such epochs are peneplanation, development of extensive weathering crusts, origin of scattered grabens or their belts, intensified rifting, and basaltic volcanism, and hydrothermal activity.

The paper provides the geological, mineralogical, and geochemical characteristics and distribution features of pyrite deposits in Rudny Altai and Southern Urals metallogenic belts. Their similar and different features are elucidated. A common feature of these regions is their close relation to island arc volcanism and large scale of mineralization that forms the world's largest pyrite provinces comparable among themselves and with pyrite belts of different regions of the world. Ore deposits in these regions have a node character and form separate ore areas controlled by volcanic central-type structures and subvolcanic bodies. In general ore deposits have multilayer distribution and are represented by lenticular, rarely tabular bodies, often localized among the hydrothermally altered rocks of quartz-sericite-chlorite and quartz-sericite composition. All deposits are attributed to the pyrite formation and include compositionally similar mineral types such as chalcopyrite-sphalerite-pyrite and gold-barite-polymetallic. Most of the deposits in these regions have a multistage origin and nearly the same mechanism of ore deposition with similar physicochemical conditions of mineralization. The specific of the regions is related to different geodynamic conditions of their formation. The Southern Urals deposits formed within the ensimatic island arcs developed on the oceanic crust while the Rudny Altai deposits occur in the ensialic island arcs developed on the crust of the continental type. This fact is responsible for the difference in volcanism and composition of mineralization.

The work is dedicated to one of the most interesting areas of the Southern Urals - Sakmara and Vozneseka-Cissakmarian zones which are identified with the Main Uralian Fault. The analysis of geological, facial and petrologic-geochemical data for volcanic complexes, forming the zone was made. The two main associations of volcanic rocks are sorted out: 1) continental-oceanic rift; 2) suprasubduction volcanic arc. Island arc volcanites of suprasubduction association are not discussed here. The first association (Є-S₁) contains the following groups of volcanites: 1) continental subalkaline basalt trap formation (Mednogorsk and Kuragan formations) (Є₁-O₁); 2) transition from continental to oceanic basalts moderately alkaline and tholeiitic series (O₁?-O₂) in the lower part of the Polyakovka and Dergaish complexes, located respectively in the northern and southern parts of the Voznesensk-Prisakmarian zone; 3) oceanic basalts (O₂-S₁), forming the upper part Polyakovka and Dergaish complexes; 4) suboceanic basalts of Bauluss complex (O₂), present with oceanic transient to island-slope basalts. The analysis of trace elements distribution has been done for basalts and less for intermediate volcanic rocks of the first association. According to chemical specifications of volcanic rocks and REE distributions the conclusion of intra-plate type of the first group volcanic rocks was made. Transitional and oceanic basalts were identified as trappoid-type oceanic formation. The absence of N-MORB basalts of oceanic stage may be related to the intra-continental nature Ural Ocean. Pulling of the mid-ocean ridge in subduction zone is also possible.

New geochemical data on carbonate and sulphate evaporates of Kungurian stage of the Permian system showed a complicated element distribution which is defined both sedimentary features and its further evolution. The main geochemical specialization of trace elements is determined not so much by sea water chemistry as presence of the terrigenous materials from the Urals femic rocks destruction. Epigenic transformation of evaporites leads to element losing and formation of new minerals (pyrite, celestite, barite, fluorite, powellite, vanadinite, iron and manganese hydroxides).

This article presents the results of detailed study of geologic structure and composition of Munilkan massif of the Main batholith belt of Verkhoyansk-Kolyma mesozoides (Tas-Khayakhtakh Ridge). Granites include numerous xenoblocks of gabbro, dolerites and subvolcanic granites they are intruded by fissure bodies and dikes of leucogranites-alaskites and trachybasalts-trachydolerites and have neutral ratio with gabbro-diorites, diorites and monzonites, which were formed during interaction of basite and granite magma. Igneous activity occurred at some stages, from Oxfordian to the end of the Early Cretaceous (157-119 Ma). Composition parameters of magmatic rocks correspond to formation of early derivatives in island-arc conditions, late derivatives - in post-collisional and intraplate conditions, that is covers the entire cycle of geologic development of Verkhoyansk-Kolyma mesozoides.

Study results of accessory zinc-bearing chromespinelides from Middle Devonian psephites of Pizhemskaya suite (D₂pg) of Ichet’yu placer-like occurrence (Middle Timan) are represented. According to electron microprobe analysis the most of chromespinelides have high-alumina contents and are classified as chrompicotites and subferrichrompicotites. Epigenetic metasomatic zincification of chromespinelides, associated phosphorus-bearing rare earth’s accessory minerals (monazite, xenotime, florencite), phosphatic rims and inclusions in rare-metal accessory minerals (ilmenorutile, columbite, zircon) are considered as possible paragenetic mineral association, that all combined are related with large-scale regional metallogenic event, with Timan’s Precambrian formation of rare and rare earth metals.

The article provides a complete list of Syrostan massif minerals, which includes 47 mineral species. It is shown that the rare-metal and rare-earth mineralization is confined to the late vein facies - granite dykes and pegmatites. Characteristic morphology and composition of new minerals of the massif: fergusonite-(Y), euxenite-(Y), polycrase-(Y), broggerit, thorogummite, and minerals already known: samarskite-(Y), columbi-te-(Mn), ilmenite, ilmenorutile, zircon, cyrtolite, allanite-(Ce) are given. Previously, it was found that allanite and titanite make the largest contribution to the balance of REE in the rocks of the main phases of the massif. These studies let to distinguish the new specialization for the massif - Nb-Ta-Ti-Y-REE-Zr-Th-U, connected with the rare-earth-rare-metal minerals association of vein granites and pegmatites.

Bittern brine nature of fluid inclusions in magnesite of Ismakaevo deposits are confirmed not only by data of Cl-Br ion systematics, but also by methods of microthermometry. The mean value of salinity of inclusions in magnesite is 23.6 wt % NaCl eqiv. (variations 20.7-25.8). In the salt composition of the inclusions, according to the eutectic temperature at microkryometry study (-50.8...-56.2°C), dominate magnesium, sodium and calcium chlorides. Homogenization temperature of two-phase inclusions occurs within the interval 184-279°C (average 224°C). High salinity fluid inclusions (24.1-24.9 wt % NaCl eqiv.) and stable temperature homogenization (216-245°C) are observed also in metasomatic fine-grained (icy) quartz, syngenetic with magnesite. Giant-grained milky-white later quartz has a lower salinity (11.5-17.1 wt %) and homogenization temperature (169-245°C).