Geologicheskii Vestnik

The study of deep continental boreholes revealed significant vertical variations in heat flow. This fact still has no satisfactory explanation. One possible cause could be the effects of past climate changes, namely changes in the Earth’s surface temperature. The paper discusses some consequences of accounting for the influence of paleoclimate on the measured heat flow using the example of the platform part of the Republic of Bashkortostan. A numerical simulation of the influence of paleoclimate on the distribution of the thermal field in the borehole was performed using two models of past climate changes. The first model, adopted earlier, includes two major climatic episodes of the past, the Würm glaciation 80–10 thousand years ago, and the Little Ice Age, 600–150 years ago. The second model uses the climatic curve for the Meso-Cenozoic, which additionally takes into account the warming that began about 65 Ma, reached its maximum about 45 Ma, and followed by a cooling that continued with some fluctuations until the present time [Velichko, 1987]. It is shown that, in the analysis of vertical variations in heat flow, the use of a model of past climate changes, taking into account more distant large climatic events than has been done previously, allows us to estimate the paleoclimate influence as much more significant than previously thought. However, at this stage of the research, with the accepted models of temperature changes at the Earth’s surface, the vertical variations of the heat flow established by the results of experimental geothermal studies cannot be explained only by the influence of the paleoclimate. To solve the problem, we need a detailed study of the thermophysical properties of rocks, high-quality temperature measurements in wells, and improvement of the model of past climate changes in the region under study.

Heat flow, paleoclimate, vertical variations

• Velichko A.A. (1987). Struktura termicheskikh izmenenii paleoklimatov mezokainozoya po materialam izucheniya Vostochnoi Yevropy [Structure of thermal changes in the Meso-Cenozoic paleoclimates based on materials from studies of Eastern Europe] // Klimaty Zemli v geologicheskom proshlom. M.: Nauka, 5–43. (In Russian).
• Galushkin Yu.I. (2007). Modelirovanie osadochnykh basseinov i otsenka ikh neftegazonosnosti [Sedimentary basins modeling and assessment their oil-gas generation]. M: Scientific World. 457 p. (In Russian).
• Golovanova I.V. (2005). Teplovoe pole Yuzhnogo Urala [Thermal Field of the South Urals]. M.: Nauka. 189 p. (In Russian).
• Golovanova I.V., Valieva R.Yu. (2006). Novye otsenki amplitudy vyurm-golotsenovogo potepleniya na Yuzhnom Urale po geotermicheskim dannym [New estimates of the magnitude of the Würm-Holocene warming in the Southern Urals from geothermal data] // Geological Collection No. 5. Information Materials. DizainPoligrafServis, Ufa, 201–203. (In Russian).
• Golovanova I.V., Puchkov V.N., Sal’manova, R.Yu., Demezhko, D.Yu. (2008). Novyi variant karty teplovogo potoka Urala, postroyennyi s uchetom vliyaniya paleoklimata [A New Version of the Heat Flow Map of the Urals with Paleoclimatic corrections]. Dokl. Earth Sci., 422 (7), 1153–1156. [In Russian]. DOI: 10.1134/S1028334X08070350
• Golovanova I.V., Selezneva G.V., Smorodov E.A. (2000). Rekonstruktsiya poslelednikovogo potepleniya na Yuzhnom Urale po izmereniyam temperatury v skvazhinakh [Reconstruction of postglacial warming in The Southern Urals using the temperature logging data]. Geol. Sb. (1), 113–116. (In Russian).
• Demezhko D.Yu. (2001). Geotermicheskii metod rekonstruktsii paleoklimata (na primere Urala) [Geothermal method for paleoclimate reconstruction (examples from the Urals, Russia)]. Yekaterinburg: UB RAS, 144 p. (In Russian).
• Klimenko V.V., Klimanov V.A., Fedorov M.V. (1996). Istoriya srednei temperatury severnogo polushariya za poslednie 11 000 let [History of average temperature in the northern hemisphere for the last 11000 years]. Dokl. of the Academy of Sciences of the USSR, 348 (1), 111–114. (In Russian).
• Pimenov V.P., Popov Yu.A., Klimanov V.A. (1996). Vertikal’nye variatsii teplovogo potoka i paleoklimat [Vertical variations of heat flow and paleoclimate]. Izv., Phys. Solid Earth, 32 (6), 547–554. (In Russian).
• Popov Y.A., Romushkevich R.A., Popov E.Y., Bashta K.G. (1999). Results of Drilling and Investigating Super-Deep Ural Well; Nedra Publ.: Yaroslavl, Russia, 77–88. (In Russian).
• Sal’nikov V.E. (1984). Geotermicheskii rezhim Yuzhnogo Urala [Geothermal Regime of the South Urals]. M.: Nauka. 88 p. (In Russian).
• Chekhonin E., Popov Y., Peshkov G., Spasennykh M., Popov E., Romushkevich R. (2020). On the importance of rock thermal conductivity and heat flow density in basin and petroleum system modelling. Basin Res. 32, 1261–1276. DOI: 10.1111/bre.12427
• Demezhko D.Yu., Golovanova I.V. (2007). Climatic changes in the Urals over the past millennium — an analysis of geothermal and meteorological data // Climate of the Past. 3, 237–242, (www.clim-past.net/237/1/2007/).
• Demezhko D.Yu., Ryvkin D.G., Outkin V.I., Duchkov A.D., Balobaev V.T. (2007). Spatial distribution
  of Pleistocene / Holocene warming amplitudes in Northern Eurasia inferred from geothermal data // Climate of the Past. 3, 559–568. (www.climpast.net/3/559/2007).
• Emmermann R., Lauterjung J. (1997). The German continental deep drilling program KTB: Overview and major results. J. Geophys. Res. 102, 18179–18201. DOI: 10.1029/96JB03945
• Jouzel J., Lorius C., Petit J.R., Genthon C., Barkov N.I., Kotlyakov V.M., Petrov V.M. (1987). Vostok ice core: acontinuous isotope temperature record over the last climatic cycle (160 000 years) // Nature. (329), 403–408. https://doi.org/10.1038/329403a0
• Kukkonen I.T., Golovanova I.V., Khachay Yu.V., Druzhinin V.S., Kosarev A.M., Schapov V.A. (1997). Low Geothermal heat flow of the Urals fold belt — implication of low heat production, fluid circulation or palaeoclimate? // Tectonophysics. 276, 63–85.
• Majorowicz J., Wybraniec S. (2010). New terrestrial heat flow map of Europe after regional paleoclimatic correction application. Int.J. Earth Sci. (Geol Rundsch). DOI: 10.1007/S00531‑010‑0526‑1
• Mottaghy D., Schellschmidt R., Popov Y.A., Clauser C., Romushkevich R.A., Kukkonen I.T., Nover G., Milanovsky S. (2005). New heat flow data from the immediate vicinity of the Kola super-deep borehole: Vertical variation in heat flow confirmed and attributed to advection // Tectonophysics. 401, 119–142. DOI: 10.1016 / j. tecto. 2005.03.005
• Popov Y., Pevzner S., Pimenov V., Romushkevich R. (1999). New geothermal data from the Kola superdeep well SG-3 // Tectonophysics. 306, 343–366. DOI: 10.1016/S40–1951(99)00065–7
• Popov Y., Spasennykh M., Shakirov A., Chekhonin E., Romushkevich R., Savelev E., Gabova A., Zagranovskaya D., Valiullin R., Yuarullin R., Golovanova I., Sal’manova R. (2021). Advanced Determination of Heat Flow Density on an Example of a West Russian Oil Field. / Geosciences (Switzerland). 11 (8), 346. DOI: 10.3390/geosciences11080346