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The Mid-Tien-Shan ophiolites make up several blocks in the Chatkal Ridge, tectonically related to the type sections of the region. The study was carried out at the most representative, Karaterek, ophiolite complex, which forms a nape lying on the Silurian volcanogenic-terrigenous deposits and Middle Carbonaceous olistostrome. The Karaterek Massif is tectonically layered and is in inverse setting. It contains (1) a complex of the melanocratic basement represented by pyroxenites, antigorite serpentinites, gabbro-amphibolites, and actinolite schists and (2) volcanogenic-sedimentary cover, whose bottom is made up of apovolcanic chlorite-epidote and other schists with members of quartz-sericite and siliceous schists. Above lie phyllites, tuff sandstones, and cherts. A complex of the conodonts Drepanoistodus sp., Paracordylodus sp., and Periodon cf. aculeatus have been documented in the cherts from the Arenigian-lower Middle Ordovician, which is the first reliable dating of the ophiolites of the region. In age and composition, the Karaterek ophiolites may, probably, be compared with the Ordovician ophiolites from the eastern Urals.

A digital elevation model (DEM) is applied to morpho-tectonic analysis of the northern mountain surroundings of Lake Telestkoye. The investigation into the neo-tectonic structure of the region and vertical offset of block movements implies detection of peneplain remnants, digital elevation modelling, and interpretation of aerial and satellite imagery. Lineaments expressed in the surface topography and/or distinguished on aerial and satellite images were divided into three groups. Those of the first two groups are different kinds of normal faults, and the third-group lineaments without geomorphically expressed vertical component have been interpreted as eroded structures of the pre-Cenozoic basement. Structures of the three types often belong to single lineament, which may indicate reactivated and stable neotectonic segments of the old basement faults. The revealed neo-tectonic blocks are rarely larger than a few kilometers across. Most of normal faults occur on the sides of the Teletsk and the adjacent Kamga and Koldor grabens, where vertical offset of recent block movements reach their maximum of 400-1200 m; in other grabens, the offset is mostly under 100-300 m. The surface topography of the region is strongly controlled by tectonics, evident from long V-shaped river valleys along zones of weakness. Some valleys are up to 600-800 m deep, and the total topographic gradient is 1600 m. In addition to tectonic factors, intense erosion is caused by recent lowering of the Lake Teletskoye level which is the regional base level of erosion.

To predict the petroleum potential, we used stratigraphic, tectonic, lithologo-facies, and geochemical criteria. We have considered their significance and estimated the petroleum potential from a total of criteria. The structures of the Toarcian, Pliensbachian, and Hettangian-Sinemurian regional reservoirs of the Lower Jurassic have been characterized. The low petroleum potential of the reservoirs is due to the following factors: intricate structure, low and very low values of capacity-filtration parameters of reservoir rocks, widespread sealing beds of poor and very poor quality, low oil-generating potential of oil source rocks, and a high degree of catagenetic transformation of OM, as well as nearly ubiquitous saturation of reservoirs with formational waters.

Time-domain electromagnetic (TEM) soundings were performed in the vicinity of a plant in Saratov town, Russia, to detect hydrocarbon pollution of groundwater and to trace possible pollution flows in drainage zones. The presence of hydrocarbons in rocks is indicated by high electrical resistance and induced polarization (IP) effects found in many TEM curves. Calculations show that the polarizability is the ratio of the excess electrical conductance to the electrical conductance in pores. Relaxation time was found to be controlled mainly by the radius of pores in water-saturated sediments. IP effects can be recorded by TEM soundings in wet sediments with imperfect phase relationships if the pore radius is the in the range of 10

Differential-normalized electrical measurements (DNEM) have shown their efficiency in petroleum prospecting. The method implies detection of oil and gas deposits from polarization anomalies in haloes around rocks altered under the effect of the hydrocarbon pool. Polarization in the geo-electric section is determined layer-by-layer using space and time derivatives of the TEM process and differential-normalized parameters.

The State Unitary Enterprise for Arctic Sea Engineering-Geological Expeditions (SEA ASIGE), Murmansk, carried out surveys in the north-eastern Pechora Sea. As a result, peculiar structures were revealed at the top of the sedimentary cover and anomalous features in the bottom topography. The anomalous bottom features are Pingo-like (Bulgunnyakh-like) rises with the base 20-60 to 100-130 m wide and with a relative altitude of 10-25 m. These rises are drastically highlighted on the smooth gentle surface of the bottom. They are made up of frozen ice-saturated deposits. On the domes of diaper-like uplifts, the roof of frozen icy deposits occurs at a depth of less than 0.5 m beneath the surface of the bottom, and their thickness reaches 100 m and more. At the sites between these uplifts the roof of the frozen grounds lies at a depth of about 15-20 m from the bottom surface with the thickness of the frozen unit of about 30 m. One of the wells drilled between diaper-like uplifts penetrated an overpressure gas accumulation at a depth of 50 m below the bottom surface.

A geographically related database called MAGIC has been developed, using GIS (Geographic Information System) technology, for MArine Gas seeps and seep IndiCators. A complementary bibliographic database (GASREF) stores details of related publications. The databases include data relating to natural seabed gas seeps and features such as pockmarks, cold seep communities, and methane-derived carbonates which are known to be found in association with seeps. The databases are compiled from published reports (so far restricted to those written in English), and users are able to interrogate the system for specified features from user-defined areas.

Concentrations of water-dissolved methane were measured on the eastern shelf and slope of Sakhalin. Seasonal variability of water structure is chiefly responsible for seasonal differences in methane concentrations in the water body. In the shelf zone the maximum flow of methane to the atmosphere occurs in the cold season; in summer, it is much weaker. The cold season is also the time when the methane-saturated shelf waters reach intermediate depths on the continental slope. In summer, the shelf waters stop sliding down the slope; therefore, no methane anomaly is observed at intermediate depths. Methane concentrations at latitudinal profiles vary from year to year, which is possibly due to variations in seismotectonic activity of the region.
Our observations are important for calculation of the flow of methane from the Earth's interior to water and from water to atmosphere in the western Sea of Okhotsk. The available data show that there are natural sources of methane supply to the atmosphere which depend on season and seismotectonic activity of fault zones, generators and conduits of methane flows. The methane flows in the Sea of Okhotsk participate in the global process of its supply and increase in the atmosphere, which is, likely, responsible for changes in climate (warming) and destruction of the ozone layer.