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A combined palynological and paleomagnetic study of core samples of Upper Cretaceous and Cenozoic deposits from four boreholes drilled in the Upper Ob' region has been carried out to provide materials for the State Geological Map-200. Palynological and paleomagnetic descriptions have been performed. Fourteen spore-and-pollen assemblages have been recognized in the deposits under study. They characterize the marine Eocene (Lyulinvor and Tavda Horizons), continental Paleogene (Atlym, Novomikhailovka, and Zhuravka Horizons), and Neogene (Abrosimovka, Beshcheul, Tavolzhan, and Pavlodar Horizons). Features of flora changes at Cenozoic borderlines (Eocene-Oligocene, Oligocene-Miocene, and Middle-Late Miocene) and their stratigraphic significance are outlined. A paleomagnetic section has been compiled for borehole 10. It includes 19 major magnetozones of different polarities: nine in the Paleogene, eight in the Neogene, and two in the Quaternary. They correspond to the rank of orthozones, paleobotanically characterized and referred to the regional stratigraphic scheme. Some of these orthozones are referred to the Berggren time scale. All these data allowed subdivision of the Upper Cretaceous and Cenozoic deposits under consideration, estimation of the completeness of the section, rock dating, and refinement of the stratigraphic volume of the Upper Cretaceous and Cenozoic formations and regional horizons exposed in the boreholes.

The Pleistocene subaerial sequence of West Siberia and other regions of temperate climate formed in a continuous-discontinuous mode during late stages of the Matuyama paleomagnetic epoch and the whole Brunhes epoch. This sequence has a cyclic structure. Each cyclite includes three climatoliths, which reflect changes from warm to cold environment. Comparison of the structures of subaerial and other deposits indicates that the subaerial sequence reflects multiple cyclic changes of environment from warm-arid (loess deposits) to warm humid (soil) and then to cold humid (overmoistening and cryogenic deposits).
The recent upper cyclite, belonging to deglaciation and the Holocene, is not complete. The present epoch of soil formation will give way to cooling with the appearance of permafrost in the nearest geologic future. Comprehensive investigation of subaerial deposits is the main line of inquiry in the development of the glaciation theory. It is important to correlate these deposits with the processes occurring in the off-glacier, near-glacier, and glacier zones. All predictions of the future climate should take into account the knowledge of subaerial deposits.

We investigate the fault geometry and kinematics of Holocene active compressional structures in the Mondy basin and its surroundings (western termination of the Tunka system of rift basins) and continue the discussion on the M = 7 Mondy earthquake of 4 April 1950. The Holocene reverse-oblique motions along the W-E trending Mondy and Ikh-Ukhgon faults are interpreted in the context of the Late Cenozoic evolution of a flower structure, on the basis of deciphered digital SPOT (10 m resolution) and Landsat (30 m resolution) imagery and field geomorphological measurements.

Late Holocene vegetation and climate have been reconstructed from pollen spectra and plant remnants in peat core section near Lake Yarma, 1320 m asl (Oka Ridge, East Sayan mountains, southern East Siberia), and ¹⁴C dating. The reconstructed evolution of local and regional vegetation records alternating humid and arid climate cycles through the past 6 kyr. The reconstruction of short climatic episodes in the historic (Fernau) stage of glacier activity about 2750 years BP and in the Little Ice Age about 500 years BP have been obtained for the first time for this territory.

The Vendian-Early Cambrian, Middle Cambrian, and Early Ordovician volcanosedimentary deposits of the Martaiga block of the Kuznetsk-Alatau paleoisland arc (55.5

The paper presents results of integrated detailed surveys by a Simrad EM-12 S120 multibeam echosounder, a MAK-1M deep-towed side-scan sonar, dragging, and gas measurements in surface water on the Caucasian continental slope in the Russian Black Sea. The combined use of these methods proved its efficiency in hydrocarbon exploration in folded and faulted regions of steep continental slopes.

We present results of study of contact rocks from the Nyurundukan ultramafic-mafic massif in the northern Baikal region. The host metabasites metamorphosed in the conditions of amphibolite facies are shown to have undergone high-temperature (T ~880

We have obtained more than 30 radiothermoluminescence (RTL) dates for loose sediments from the Tunka Rift, lithologically divided into sandy, boulder-pebble, terrace, slope, and cover formations. The sandy fluvial sediments are dated to 76.00-31.50 Ka, and the eolian sediments formed from them, to 16.12-8.31 Ka. We have first determined the age of the Mondy moraine in the west of the Tunka Rift - 70.00-72.00 Ka. The age of the ancient alluvium buried under it varies from 101.5 to 132 Ka. The oldest sediments of this complex (153 Ka?) occur in the base of the ancient alluvium of the Ikhe-Ukhgun' River, at its intersection with the Nilov spur. Radiocarbon and RTL dates obtained for the base of the lower terraces of the Irkut River made up of Holocene deposits yield an age of 53.40 and 40.06 Ka, respectively. The lower part of the slope sediments is dated to 22.00 Ka, and the pebbles overlapping the bases and slopes of young volcanoes in the Tunka depression, to 39.00 and 70.00 Ka, respectively.

The roots of disagreement on the energetics of exogenous processes have been analyzed in the context of modern views on water-rock interaction. Results of thermodynamic analysis of weathering reactions are reported. It is shown that the formation of supergene clays involves two different geological processes: hydrolysis of aluminosilicates and binding of large amounts of water. Relative to the free water, the bound water has a higher free energy of formation. This difference considerably changes the energetics of hydrolysis reactions, which actually are all endothermic. The conclusion is made that physically bound water and, therefore, clays bear large stocks of accumulated solar energy. This fact proves that oriented inner evolution and self-organization took place in inorganic matter like those known in biogenic systems, with a genetic relationship existing between them.

Seventeen Middle Paleozoic haloes of kimberlite minerals have been distinguished in Middle Devonian, Early Carboniferous, and younger terrigenous collectors in the south of the Siberian Platform. The paleogeographic settings in which they formed rule out supply of material from the already discovered bodies and suggest erosion of numerous local coeval primary sources. Comparison of the haloes with the model for kimberlite field manifestation in terrigenous collectors, elaborated on the basis of known kimberlite fields in Western Yakutia, evidences that they are cut off from primary sources. We predict the existence of Middle Paleozoic kimberlites buried under Permian-Triassic deposits in southern Siberia. These kimberlites, apparently, differ from the known West Yakutian pipes in manifestation of earlier phases of intrusion and in essentially pyrope composition of indicator minerals.