Мурманская миля. 2016, № 3.

EXPLORATIONS Fig. 4. Fo re ca s t s e c tio n o f o il and gas g e o lo g ic a l pa ram e te rs . Р и с .4 . П р о гно зны й р а з р е з н еф те га зо ге о л о ги ч е с ки х парам етров . 16 Predicted sections of geo­ logical oil-and-gas parameters on a scale of 1 : 1 0 0 0 0 0 0 were plotted. Faults play a significant role in formation of hydrocarbon prospects of the northern Bar­ ents Sea shelf, the most part of that is practically traced at full thickness of the sedimen­ tary cover, dying out in upper horizons of the Cretaceous se­ quence. One recognized trap evolution zones of different types: anticline arched, massive and lithologic-stratigraphical traps. Lithologic, stratigraphic, fault hydrocarbon traps are recog ­ nized in M iddle Permian - Ju ras­ sic interval of the section w ithin the depth range of 1 ,000-4,000 m and they are mainly con ­ fined to slopes of large positive s tructu res of a regional step of the Franz V ictoria (hem i- swells of V ictoria, Dezhnev, Shirshov), the A leksandrovsky zone of uplifts (Pineginsky and Musatovsky megaswells), the A lbanovsky-Gorbovsky Thresh­ old (Trubyatchinsky and Orlov megaswells), a regional step of the Zapadny Fobos. Regarding the a ccessibility by occurrence depth of expected hydrocarbon reservoirs, the given areas are the most favorable ones fo r drilling operations. Six hydrocarbon-bearing se­ quences and potential hydro­ carbon-bearing ones are recog­ nized in the sedimentary cover section: Ordovician - Upper De­ vonian potential hydrocarbon- bearing sequence, Upper Devo­ nian - Lower Permian potential hydrocarbon-bearing sequence, M iddle - Upper Permian po­ tential hydrocarbon-bearing sequence, Triassic hydrocar­ bon-bearing sequence, Juras­ sic - Neocomian hydrocarbon- bearing sequence, Cretaceous potential hydrocarbon-bearing sequence (Fig. 4). Within the limits of the north­ ern Barents Sea shelf, the west­ ern Barents Sea and eastern Barents Sea petroleum provinc­ es are recognized. The western Barents Sea petroleum province within the limits of the generali­ zation area is represented by the central Barents Sea potential oil and gas bearing region, struc­ turally, the sedimentary cover bottoms of that correspond to the Franz Victoria and Aleksan­ drovskaya regional steps. In composition of the eastern Barents Sea petroleum prov­ ince, one detects the north Bar­ ents Sea potential oil and gas bearing region, the Albanovsky- Gorbovsky potential oil and gas bearing region, the Saint Anna potential oil and gas bearing region, the Admiralteyskaya - Prinovozemelskaya independent potential oil and gas bearing re­ gion. Within the limits of oil-and- gas bearing region, the following potential oil-and-gas bearing ar­ eas are defined: the Franz Victo­ ria, Aleksandrovsky (the central Barents Sea potential oil-and- gas bearing region), Severny and Pineginsky (northern Bar­ ents Sea potential oil-and-gas bearing region), Trubyatchinsky in composition of Albanovsky- Gorbovsky potential oil-and-gas bearing region, Zapadny Fobos in composition of potential oil- and-gas bearing region of Saint Anna, Zhelaniya Cape and Admi- ralteysky (Admiralteysky-Prino- vozemelskiy independent poten­ tial oil-and-gas bearing region). (F ig .5 ). Forecast resources of the sedimentary cover of the north Barents Sea shelf to the depth of 7,000 m amounts to 14.84 bln TOE, a share of recoverable re­ sources from them is 12.57 bln TOE. The performed studies al­ lowed to prode a model of the north Barents Sea shelf geologi­ cal structure taken as a basis of geological oil and gas zonation and prediction of the region hy­ drocarbon potential. In the sedimentary cover of the northern Barents Sea area, there have not been detected sufficiently large anticline up­ lifts, except fo r the Varnekskaya structure. However, a more de ­ tailed investigation of the latter one showed that possible traps were mostly stratigraphic ones determ ined by specific sedi­ mentation conditions of Paleo­ zoic deposits which are p ro ­ posed to be more promising ones in respect of oil-and-gas content. Besides, it may be stated that due to various sedimenta­ tion conditions in conjunction with depositional breaks allow suggesting a wide trap evolu­ tion of stratigraphic type in all stratigraphic ranges and some difficulties determ ined in this connection while estimating hy­ drocarbon potential of the north­ ern Barents Sea area. MURMANSK MILE • 3-2016

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