PETROLEUM POTENTIAL OF THE UPPER DEVONIAN COMPLEX TIMAN-PECHORA OIL AND GAS PROVINCE

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Currently in the Timan-Pechora oil and gas province (TPОGP) opened about 100 hydrocarbon deposits in the upper Devonian complex. The discovery of large oil deposits in the 80-ies of the 20th century in the upper Devonian complex on Kharyaga and Pisarska fields was the incentive to increase exploration for these deposits. Search works on upper Devonian complex were isolated in a separate direction. This paper presents a brief description of the characteristic of the deposits in the upper Devonian complex TPОGP. Oil deposits in this complex dedicated to a wide stratigraphic range (from domanic to numilog horizon). They are associated with the carbonate formations of different nature - reef arrays, silt hills, shelf buildings, formation carbonates in “backreef” zone, depression Dominicaine sediments at the foot of the reef massifs, with paleomagnetism in the area of uncompensated depression. Petroleum potential of the considered complex is provided by a combination of reservoir rocks, local and zonal tires, traps, as well as the presence in the complex, and the underlying Paleozoic sediments of petroleum generating ones strata. Zone reefs are complex areas of oil and gas accumulation. These long linear areas favorable for the accumulation of hydrocarbons in the process of lateral and vertical migration. Source lateral migration are domanic and Dominicaine deposits, vertical - underlying sediments of the Paleozoic. The outer contour of the distribution of hydrocarbon deposits in the study area coincides with the reef area domanic age. This reef area of the upper Devonian middle and low-capacious carbonate reservoirs in “backreef” zone during testing were obtained only tributaries water. This is probably due to several causes: 1) the relative remoteness of the petroleum generating ones (domanic and domeniconi) strata in the upper Devonian complex; 2) the presence of barriers to lateral migration of hydrocarbons in the form of reef areas, which are already in sedimentary basins represented a tectonic-sedimentary traps and could catch hydrocarbons; 3) lack of generating hydrocarbons clay-sand-silt-middle Devonian sediments and distribution of red-colored facies in the sections of the Silurian and lower Devonian. Major deposits of oil in the upper Devonian complex TPОGP concentrated under local and zonal tires, which rarely overlap reef strata, and they are most often located above overreef sediments.