Evolution in information on crustal geothermal parameters due to application of advanced experimental basis

On the importance of rock thermal conductivity and heat flow density in basin and petroleum system modelling

“…Spatial and temporal variations in HFD are derived from a geologically constrained model or, less commonly, from simplified analysis, i.e., using the McKenzie model (McKenzie, ) or its modifications in the case of extensional basins. Regardless of the approach, specialists rely on present‐day HFD maps, which frequently involve significant errors (Popov et al, , ). Moreover, HFD geohistory is sometimes locally modified during calibration, which leads to variations in temperature/maturity without proper geological justification.…”

“…Our long‐term experience (1985–1991, 1996–2014) of geothermic research in unique deep and superdeep continental scientific wells in former USSR, Germany, USA, Mexico, etc. with numerous temperature measurements in wells and more than 30,000 samples investigations (Popov et al, ) shows that (a) vertical HFD variations must be recorded, (b) heat generation has little effect compared with the influence of paleoclimate (tens of percent), fluid migration in the well and the effects of averaging of the thermal gradient, (c) the results are distorted due to systematic errors in the use of traditional contact methods of thermal conductivity measurements, the neglect of anisotropy, the small volume of the core under study at a substantial heterogeneity of the sections. The neglect of the above factors does not allow registering significant local variations and the general trend of heat flow along the wells.…”

“…Analyses of previously published heat flow data and comparisons with reliable estimates for the same tectonic units based on results from super‐deep and deep scientific wells (Clauser et al, ; Emmerman & Lauterjung, ; Fuchs & Balling, ; Kukkonen et al, ; Popov et al, ) lead to the conclusion that early HFD data often contain systematic errors of 40%–130%. The reasons for this are twofold: unsatisfactory quality of the thermal conductivity measurements (Pasquale, Chiozzi, Verdoya, & Gola, ; Popov et al, ); and the features of early approaches used for HFD estimation.…”

“…The role of thermal petrophysics in modelling basin and petroleum systems has been growing in recent years for at least three major reasons. First, the results of deep continental scientific drilling have led to dramatic changes in the understanding of the thermal regime at substantial depths in the interior of the Earth (Emmerman & Lauterjung, ; Popov, Popov, Chekhonin, Spasennykh, & Goncharov, ). Second, temperature is a key parameter for determining the transformation of kerogen into oil and gas, and its evaluation is impossible without reliable data on thermal properties.…”

“…Moreover, assessing the present‐day basal HFD is a complex problem. Previous experimental data on heat flow obtained with traditional technique are often significantly underestimated (e.g., Emmerman & Lauterjung, ; Kukkonen, Rath, Kivekäs, Šafanda, & Čermak, ; Popov, Pevzner, Pimenov, & Romushkevich, ; Popov et al, ), that should be taken into account. Using unreliable HF data decreases the quality of thermal history reconstructions.…”