Vol. 326 No. 1 (2015)
Petroleum potential of the lower cretaceous reservoirs of Nyurol'ka megadepression
The relevance of the research is caused by the need of reproduction and expansion of oilfields area resource base in Tomsk region. This direction in development of oil and gas complex, increase of raw material potential is resources-saving, minimizing the volume of investment for exploration, mastering and subsequent extraction. The main aim of the research is to identify and to propose the priority areas for exploration and development of oil and gas complex of the Lower Cretaceous in the territory Nyurol'ka megadepression and structures of its framing. Objects of researches are the slope (clinoform) parts of Neocomian cyclites - achimovka reservoir, and undaform (shallow-shelf) parts of Neocomian cyclites, shelf reservoir. Neocomian deposits are poorly studied and characterized by a complex type of traps and difficult identification of productive layers. Methods of researches: reservoirs geomapping; computer paleotectonic reconstructions and paleotemperature modeling of sedimentary cover, including oil source sediments; selection by geotemperature criterion and mapping the centers of Bazhenov oil intense generation; evaluation of generated oil density distribution; evaluation and analysis of oil resource relative density distribution in Neocomian achimovka and shelf reservoirs; zoning of reservoirs according to the prospectivity degree. Research results. The authors have given the volumetric-areal characterization for Neocomian Achimov and shelf reservoirs, plotted the maps of the total thickness of seven cyclites of Achimovka and five cyclites in shelf sediments; reconstructed the thermal history of bazhenov sediments in sections of thirty-nine deep wells; selected and mapped paleosources of Bazhenov oil generation on 18 key moments of geologic time; plotted the map of distribution of generated oil resource densityand the maps of distribution of relative dens ty of the accumulated resources; carried out zoning for Achimovka and shelf reservoirs; proposed the areas of priority for searching for Achimov reservoir - the area of south-eastern slope of Kaymysov arch, junction zone of Chuzik-Chizhap and Shingin mezosaddles, thirty kilometer are of sub-East-West extension in the central part of Nyurol'ka megadepression, and for shelf reservoirs - area of East-West extension, which covers the eastern half of Kulan-Igay depression and the western part of the Festival shaft (3500 km2 ) and the junction zone of the northern side of Nyurol'ka megadepression with the eastern slope of Kaymysov dome and south-western slope of Sredne-vasyugan megaswell (500 km2 ).
Keywords:
social media, shelf deposits and Achimovka reservoirs of the Neocomian deposits, thermal history of the Bazhenov sediments, density of the resources of generated oils, Nyurol'ka megadepression


