OIL AND GAS CONTENT OF WEATHERING CRUST AND PALEOZOIC IN KOLTOGOR MEZODEPRESSION (NORTH-WEST OF THE TOMSK REGION)
The relevance of the research consists in the necessity of reproduction of raw materials base with hard-to-recover reserves in the Pre-Jurassic oil and gas complex due to the depletion of the «classic» oil and gas horizons of Western Siberia. The aim of this paper is to identify perspective areas fo...
| Main Authors: | , , |
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| Format: | Article |
| Language: | Russian |
| Published: |
Tomsk Polytechnic University
2019-09-01
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| Series: | Известия Томского политехнического университета: Инжиниринг георесурсов |
| Subjects: | |
| Online Access: | http://izvestiya.tpu.ru/archive/article/view/2259/2058 |
| Summary: | The relevance of the research consists in the necessity of reproduction of raw materials base with hard-to-recover reserves in the Pre-Jurassic oil and gas complex due to the depletion of the «classic» oil and gas horizons of Western Siberia. The aim of this paper is to identify perspective areas for geological exploration in the Pre-Jurassic oil and gas complex in the Koltogor mezodepression – on the lands of the developed oilfield infrastructure of the Tomsk region. The object of the study is the Pre-Jurassic reservoirs of the Permo-Triassic weathering crust and Paleozoic basement, within boundaries of the oil source Togur suite. The deposits in the weathering crust are associated with reservoirs formed over clay-siliceous, carbonate rocks, volcanic rocks of acid composition. In the inner Paleozoic, reservoirs correlate with secondary reservoirs formed to limestone and granite. Method. The study is conducted within the framework of the concept of primarily vertical migration of hydrocarbons. The previous restoration of thermal history of the Togur suite, cumulatively taking into account the temperatures of the localized paleocenters of oil generation, made it possible to map the distribution of oil generation density. The subsequent integral analysis, taking into account the reservoir characteristics of reservoirs and the fault tectonics Paleozoic, is used to carry out zonal oil geological zoning of the pre-Jurassic complex and land ranking by degree of prospects. Results. The oil geological zoning of the territory with high oil and gas potential has been carried out for the reservoirs of the Weathering Crust and the basement Paleozoic reservoirs separately. The priority area in the weathering crust is the eastern part of the Cheremshan mezosaddle, its adjacent area with the northern bead of the Koltogor mezodepression and the western hillside of the Srednevasyugan megawell (about 3,500 km2). The second section, with the same level of prospects, combines the North-Chkalovsky shut-in and its adjacent area with Murasov anticlinal nose and the Trass arched dome (about 5,700 km2). The identified oil and gas potential in the Pre-Jurassic reservoirs well confirms the conducted zoning and the accepted migration concept of hydrocarbons feeding reservoirs. The reliability of the forecast of promising lands of the Pre-Jurassic oil and gas complex is determined by comparison with the results of testing deep wells and is about 70 %. |
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| ISSN: | 2500-1019 2413-1830 |