TY - JOUR AU - Usenko, A. P. AU - Usenko, O. V. PY - 2020/06/10 Y2 - 2024/03/29 TI - Analysis of geothermic parameters of oil-and gas deposits of the central part of the Dnieper-Donets depression JF - Geofizicheskiy Zhurnal JA - GJ VL - 42 IS - 3 SE - Articles DO - 10.24028/gzh.0203-3100.v42i3.2020.204705 UR - https://journals.uran.ua/geofizicheskiy/article/view/204705 SP - 127-144 AB - <p>Distribution of geothermic parameters in the central part of the DDD in the joint of Lokhvitsa and Izyum blocks has been considered in the paper. Geothermic gradient and heat flow have been calculated according to the results of measurements conducted directly in the process of drilling.</p><p>It has been found that geothermic gradient varies both with depth and area even within the limits of one deposit. Comparison with geologic cross-section shows that the leaps of gradient are connected with crossing of stratigraphic (and lithologic) borders and the changes of temperature are noticed while crossing the roof of hydrocarbon deposits predominantly in the Lower Carboniferous. In most cases they are positive. In the Devonian volcanogenic-sedimentary stratum in considerable cases negative leaps appear as well. For calculation of heat flow (HF) only the measurements were used conducted in the deep holes crossing hydrocarbon deposits. Two modes of HF distribution are fixed in many deposits that differ by 5—10 units possibly explainable by hydrogeologic isolation of different blocks of the same deposit. The leaps of gradient and fluctuations of HF values may be produced by diffluence of hydrothermal solution in porous layers of sedimentary stratum. In the Machekha gas deposit a coincidence is fixed for the depth of gradient growth and the depth of registration of hydrogeologic inversion and a zone of anomalously high pressure in the stratum.</p><p>Comparison with a map of HF, plotted by the results of temperature measurements in the wells with established heat regime demonstrates overall coincidence of HF distribution.</p><p>The margin of the Lokhvitsa and Izyum blocks is a zone of changes of many physical characteristics of the basement and shows itself in the majority of geophysical fields. In the HF map it is marked out with the increase of average values in the northern and southern sides of the DDD and with their decrease in its central part. While increased values of HF are distributed both in the west and in the east of DDD, then the similar negative anomalies are represented only in this zone.</p> ER -