An intensive magnetic anomaly within the limits of West Siberia Danilov graben-rift indicates magnetic rocks while numerous wells encountered only weakly magnetized Triassic basalts and liparites in the basement covered by thick loose Jurassic and younger sediments. The wells penetrated only the first tens meters of the basement and could not tell us about the liparites structure at depth where supposedly they may form a big single body and magnetic rocks may be situated deeper. Geological ideas on a graben-rift structure may be proved (or rejected) by a computer modeling of its magnetic properties. For the anomalous geomagnetic field interpretation, a method of volume integral equations taking into account demagnetization effect was employed. To fit a model a trial-and-error procedure was utilized. The results show that 1) at the depth some rocks are magnetized in opposite direction to the present field; 2) highly magnetized rocks (magnetic susceptibility 0.06 - 0.1SI) coming up continuously from the bottom of the model and situated under the graben; 3) the studied structure is not a graben but the rift because the continental light crust is absent.
Ivanov, K.S., Kucherov, V.G. and Fedorov, Yu.N. (2008) To the Question about Deep Origin of Oil. Proceedings ZapSibNIIGG Conference Condition, Tendencies and Problems Oil and Gas Potential of West Siberia Development, Tyumen, 160-173. (In Russian)
Nezhdanov, A.A., Ponomarev, V.A., Turenkov, N.A. and Gorbunov, S.A. (2000) Geology and Oil and Gas Bearing of Achmovskaya Thickness of West Siberia. Publisher of Academy of Rock Sciences, Moscow. (In Russian)
Miller, S.P. and Hey, R.N. (1986) Three-Dimensional Magnetic Modeling of a Propagating Rift, Galapagos 95°30'W. Journal of Geophysical Research, 91, 3395-3406. https://doi.org/10.1029/JB091iB03p03395
Mariano, J. and Hinze, W. (1994) Gravity and Magnetic Models of the Midcontinent Rift in Eastern Lake Superior. Canadian Journal of Earth Sciences, 31, 661-674. https://doi.org/10.1139/e94-059
Mugisha, E., Ebinger, C.J, Strecker, M. and Pope, D. (1997) Two-Stage Rifting in the Kenya Rift: Implications for Half-Graben Models. Tectonophysics, 278, 63-81. https://doi.org/10.1016/S0040-1951(97)00095-4
MacLean, B.C. and Miles, W. (2002) Potential-Field Modeling of a Proterozoic Half-Graben near Blackwater Lake, Northwest Territories, Canada, and Its Implications for the Fort Simpson Magnetic Anomaly. Canadian Journal of Earth Sciences, 39, 169-187. https://doi.org/10.1139/e01-061
Bhattacharji, S., Sharma, R. and Chatterjee, N. (2004) Two- and Three-Dimensional Gravity Modeling along Western Continental Margin and Intraplate Narmada-Tapti Rifts: Its Relevance to Deccan Flood Basalt Volcanism. Journal of Earth System Science, 113, 771-784. https://doi.org/10.1007/BF02704036
Ebbing, J., Skilbrei, J.R. and Olesen, O. (2007) Insights into the Magmatic Architecture of the Oslo Graben by Petrophysically Constrained Analysis of the Gravity and Magnetic Field. Journal of Geophysical Research, 112, Article ID: B04404, 17 p.
Bridges, D.L. (2011) A Geological and Geophysical Study of the Tendaho Graben in the Afar Depression, Ethiopia: Insights into Transitional Continental Rifting. Doctoral Dissertations, Missouri University of Science and Technology, Rolla, Missouri. http://scholarsmine.mst.edu/doctoral_dissertations/2020
Alatorre-Zamora, M.A., Campos-Enríquez, J.O., Rosas-Elguera, J.G., Pena-García, L., Maciel-Flores, R. and Fregoso-Becerra, E. (2015) Chapala Half-Graben Structure Inferred. A Magnetometric Study. Geofísica Internacional, 54, 323-342. http://www.redalyc.org/articulo.oa?id=56842730003
Lopes de Castro, D. (2011) Gravity and Magnetic Joint Modeling of the Potiguar Rift Basin (NE Brazil): Basement Control during Neocomian Extension and Deformation. Journal of South American Earth Sciences, 31, 186-198. https://doi.org/10.1016/j.jsames.2011.01.005
Langenheim, V.E., Jachens, R.C., Muffler, L.J.P. and Clynne, M.A. (2016) Implications for the Structure of the Hat Creek Fault and Transfer of Right-Lateral Shear from the Walker Lane North of Lassen Peak, Northern California, from Gravity and Magnetic Data. Geosphere, 12, 790-808. https://doi.org/10.1130/GES01253.1
Obi, D.A., Ilozobhie, A.J., Lebo, S.E. and Zoogbara, E. (2017) Modeling Magnetic Basement in Relationship to Hydrocarbon Habitats in the Central Niger Delta, Nigeria. Journal of Geography, Environment and Earth Science International, 10, 1-13. https://doi.org/10.9734/JGEESI/2017/31888
Ivanov, K.S., Kormiltsev, V.V., Fedorov, Yu.N., et al. (2003) The Main Characters of Pre-Jurassic Basement Structure in Shaim Oil and Gas Bearing Region. The Way of Realization of Oil and Gas Potential of KhMAD. Proceedings of Viscientific-Pracical Conference, V.1. Khany-Mansiysk, 102-113. (In Russian)
Rybakov, M.B., Goldshtein, V.I., Holl, D., Ben-Avraam, Z. and Lazar, M. (2011) New Ideas on Sources of Magnetic Anomalies in the East Mediterranean: A Key to Ophyolites and Gabbro Intrusion Localiation. Geologiyaigeofizika, 4, 487-511. (In Russian)
Rostovtsev, N.N. (1964) Geology of the USSR. West-Siberian lowland. Geological Description, Nedra, Moscow, Vol. 44, 1-550. (In Russian)
Ivanov, K.S., Puchkov, V.N., Fyodorov, Y.N., Erokhin, Y.V. and Pogromskaya, O.E. (2013) Tectonics of the Urals and Adjacent Part of the West-Siberian Platform Basement: Main Features of Geology and Development. Journal of Asian Earth Sciences, 72, 12-24. https://doi.org/10.1016/j.jseaes.2013.02.029
Grachev, A.F. (1977) Rift Zones of Earth. Nedra, Leningrad. (In Russian)
Kucheruk, E.V. and Ushakov, S.A. (1985) Plate Tectonics, Oil, and Gas Bearing (Geophysical Analysis). VINITI, Moscow. (In Russian)
Milankovskiy, E.E. (1976) Rift Zones of Continents. Nedra, Moscow. (In Russian)
Elkin, E.A., Krasnnov, V.I., Bakharev, N.K., Belova, E.V., Dubatolov, V.N., Izokh, N.G., Klets, A.G., Kontorovich, A.E., Peregoedov, L.G., Sennikov, V.V., Timokhina, I.G. and Khromykh, V.G. (2001) Stratigraphy of Oil and Gas Bearing Basins of Siberia. Paleozoic of West Siberia. Publisher SO RAS, Subsidiary Geo, Novosibirsk. (In Russian)
Bogush, O.I., Bochkarev, V.S. and Yuferev, O.V. (1975) Paleozoic of the South of West Siberia Plane. Novosibirsk, Nauka. (In Russian)
Klets, A.G., Kontorovich, V.A., Ivanov, K.S., Kazanenkov, V.A., Saraev, S.V., Simonov, V.A. and Fomin, A.N. (2007) Geodynamical Model of Pre-Jurassic Basement—The Basis of Oil and Gas Bearing Zoning of Upper PreCambrian—Low Triassic Structural Stage of West Siberia Oil and Gas Bearing Province. Proceeding of Conference “The Way of Realization of Oil and Gas and Ore Potential of KhMAD”, Khanty-Mansiysk, 13-17 November 2007, Vol. 1, 79-90.
Fedorov, Yu.N., Ivanov, K.S., Koroteev, V.A. and Kormiltsev, V.V. (2004) Tectonic Structure of Transuralian Part of West Siberia Megabasin. Proceeding of Conference “The Way of Realization of Oil and Gas and Ore Potential of KhMAD”, Khanty-Mansiysk, 2-5 December 2004, Vol. 1, 91-102. (In Russian)
Kontorovich, V.A. (2007) Seismological Criteria of Oil and Gas Bearing of the Contact Zone of Paleozoic and Mesozoic Sediments of West Siberia. Geologiyai Geofizika, 48, 538-547. (In Russian)
Ivanov, K.S. (2016) How Much Oil Does Russia Need to Produce? Uralian Geological Journal, 6, 3-14. http://docs.wixstatic.com/ugd/15eb72_f0c0f560110b4165b2e7221570aef26e.pdf
Rudkevich, M.Ya., Ozeranskaya, L.S., Chistyakova, N.F., et al. (1988) Oil and Gas Bearing Complexes of West Siberia Basin. Nedra, Moscow. (In Russian)
Ivanov, K.S., Koroteev, V.A., Pecherkin, M.F., Fedorov, Yu.N. and Erokhin, Yu.V. (2009) History of Geological Development and Structure of the Basement of Western Part of West Siberia Oil and Gas Megabasin. GeologiyaiGeofizika, 50, 484-501. (In Russian)
Fedorov, Yu.N., Ivanov, K.S., Zakharov, S.G., Kormiltsev, V.V., Erokhin, Yu.V., Pogromskaya, O.E., Knyazeva, I.V., Ronkin, Yu.L., Karetin, Yu.S., Surina, O.V., Purtova, S.I. and Glushko, N.K. (2003) Geological Structure and Stratigraphy of Triassic Sediments of the Northern Sosva Graben. Proceeding of Conference “The Way of Realization of Oil and Gas and Ore Potential of KhMAD”, Khanty-Mansiysk, IzdatNaukaServis Vol. 1, 114-123.
Kostrov, N.P., Kormiltsev, V.V. and Fedorov, Yu.N. (2005) System of 3D Interpretation of Gravitational and Magnetic Observations with the Aim of Geological Mapping of Pre-Jurassic West Siberia Complex. GornyeVedomosti, 1, 57-61. (In Russian)
Kostrov, N.P. and Ivanov, K.S. (2017) Complex for Interpretation of the Potential Fields for Geology. Vestnik of IGG Komi Science Center of UrB RAS, 10, 3-8. (In Russian) https://doi.org/10.19110/2221-1381-2017-10-3-8
Ananieva, E.M., Vinnichuk, N.N., Ivanov, K.S., et al. (2008) On Density of Rocks of East Urals and West Siberia Basement. UrB RAS, Yekaterinburg. (In Russian)
Gusev, B.V., Metallova, V.V. and Fainberg, F.S. (1967) Magnetism of Rocks of Traps Formation of Western Part of Siberia Platform. Nedra, Leningrad. (In Russian)
Chursin, A.V., Prutyan, A.M. and Fedorova, N.V. (2008) Digital Anomalous Magnetic Field Map of the Northern, Middle, Southern Urals and Adjacent Territoties of the East-European and West-Siberian Platforms. Litosfera, 6, 63-72. (In Russian)
Kormiltsev, V.V. and Ratushnyak, A.N. (2000) Modeling of Geophysical Fields with the Help of Volume Vector Integral Equations. UrB RAS, Yekaterinburg.
Eloranta, E.H. (1986) Potential Field of a Stationary Electric Current using Fredholm Integral Equations of the Second Kind. Geophysical Prospecting, 34, 856-872. https://doi.org/10.1111/j.1365-2478.1986.tb00498.x
Kormiltsev, V.V. and Kostrov, N.P. (1999) Study of Algorithms Based on a Volume Vector Integral Equation for Magnetic Field Strength. VINITI, Moscow, 83-B99. (In Russian)
Kormiltsev, V.V. and Ratushnyak, A.N. (1995) Vector Integral Equations for a Gradient of Potential Geophysical Fields. Rossiyskiygeofizicheskiyzhurnal, 5-6, 4-10. (In Russian)
Kostrov, N.P. (2007) Calculation of Magnetic Anomaliescaused by 2D Bodies of Arbitrary Shape with Consideration of Demagnetization. Geophysical Prospecting, 55, 91-115. https://doi.org/10.1111/j.1365-2478.2006.00579.x
Sharma, P.V. (1996) Rapid Computation of Magnetic Anomalies and Demagnetization Effects Caused by Bodies of Arbitrary Shape. Pure and Applied Geophysics, 64, 89-109.
Atkinson, K.E. (1997) Thenumerical Solution of Integral Equation Soft the Second Kind. Cambridge University Press, Cambridge. https://doi.org/10.1017/CBO9780511626340
Blokh, Yu.I. (1987) Magnetic Field Calculation for Three-Dimensional Anisotropic Geological Objects with Corrections for Demagnetization. Izvestiya, Earth Physics, 23, 1003-1008.
Ivanov, K.S., Kostrov, N.P. and Manushko, E.A. (2013) Deep Structure of the Danilovskii Graben in Western Siberia: A Geological Interpretation of the Density Models. Doklady Earth Sciences, 451, 870-874. https://doi.org/10.1134/S1028334X13080102
Thébault, E., et al. (2015) International Geomagnetic Reference Field: The 12th Generation. Earth, Planets and Space, 67, 79. https://earth-planets-space.springeropen.com/articles/10.1186/s40623-015-0228-9 https://doi.org/10.1186/s40623-015-0228-9