The 3D basin modeling is fraught with a number of uncertainties, one of them being the correct reconstruction of geothermal history. The article examines the major issues that complicate the forecasting as well as the methods used to overcome them using the Pre-Caspian depression as an example. The purpose of the work is to enhance the accuracy of assessing the thermal field variations during the evolution of the Pre-Caspian depression. The account of the temperature measurements of the Earth’s surface from spacecraft can reduce forecast uncertainties. Repeated temperature measurements over a sufficiently close network from different spacecraft provide more information. However, obtaining reliable data characterizing exactly the endogenous component of the thermal field is associated with certain difficulties. Combining the results of the Earth's thermal field surface measurements with measured data from temperature surveys performed in deep wells made it possible to obtain a 3D vertical gradient model for the thermal field. The model’s evolution over time was traced using geothermal modeling in Temis Flow™ software. The modeling outputs were surface temperature and heat flow distribution maps updated based on actual well data. The results obtained demonstrate a non-uniform temperature distribution in the sedimentary cover due to halokinesis, which affects the distribution of the source rock catagenetic alteration degree: catagenetic maturity is lower under thick salt diapirs than in the salt thinning zones. The data obtained allow a more accurate assessment of potential hydrocarbon fluid generation volumes. In places at the same depth, sediments beneath the diapirs are transformed to gradation MK3-MK4, and in the interdome zone to MK5-AK1.
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