Delineation of hydrocarbon prospective areas is an important issue in petroleum exploration. The geoelectric method helps to identify attractive areas and reduces the overall drilling risk. For this purpose, induced polarization (IP) effects are mapped caused by the presence of epigenetic pyrite microcrystals in sedimentary rocks. These crystals occur in a shallow halo-shaped mineralogical alteration zone, often overlying a deeper-seated hydrocarbon accumulation. Local enrichment in pyrite results from reducing geochemical conditions below an impermeable layer. The imperfect top seal of the accumulation permits minor amounts of hydrocarbons to escape and migrate through the overlying rocks to shallower levels. During migration, hydro-carbons encounter an impermeable barrier, forming an altera-tion zone. Induced polarization logging and coring in wells confirm this working model. Geoelectric surveying visual-izes anomalies in electric potential difference measured be-tween receiver electrodes. The differentially normalized method (DNME) inverts the registered decay in potential differences, establishing a depth model constrained by seismic and petro-physical data. Diagnostic geoelectric attributes are proposed, giving a better grip on chargeability and resistivity distribution. Acquisition and processing parameters are adjusted to the target depth. Encouraging results are obtained in deeper [Formula: see text] as well as in very shallow water. Onshore, a grounded current transmitter is used. Geoelectric surveys cover different geologic settings with varying target depths. The success ratio for predicting hydrocarbon occurrences is high. So far, 40 successful wells have been drilled in Russia on mapped geoelectric anomalies. Out of 126 wells, the method produced satisfactory results in all but two cases. The technique reduces the risk attached to new hydrocarbon prospects and allows better ranking at a reasonable cost.

We compile existing seismic, gravity, radar and magnetic data, together with the subglacial bedrock relief from the BEDMACHINE project, to build the most detailed sediment model for Antarctica. We interpolate these data according to a tectonic map of Antarctica using a statistical kriging method. Our results reveal significant sediment accumulation in Antarctica with several types of sedimentary basins: parts of the Beacon Supergroup and more recent rifting basins. The basement relief closely resembles major geological and tectonic structures. The thickness of sediments has significant variations around the continent, and depends on the degree of crustal extension. West Antarctica has wide sedimentary basins: the Ross basin (thickness 2–6 km), the Filchner-Ronne basin (2–12 km) with continuations into East Antarctica, the Bentley Subglacial Trench and the Byrd basin (2–4 km). The deepest Filchner-Ronne basin has a complex structure with multi-layered sediments. East Antarctica is characterized by vast sedimentary basins such as the Pensacola-Pole (1–2 km), Coats Land (1–3 km), Dronning Maud Land (1–2 km), Vostok (2–7 km), Aurora (1–3 km), Astrolabe (2–4 km), Adventure (2–4 km), and Wilkes (1–4 km) basins, along with narrow deep rifts filled by sediments: JutulStraumen (1–2 km), Lambert (2–5 km), Scott, Denman, Vanderford and Totten (2–4 km) rifts. The average thickness of sediments for the whole continent is about 0.77 km. The new model, ANTASed, represents a significant improvement over CRUST 1.0 for Antarctica, and reveals new sedimentary basins. Differences between ANTASed and CRUST 1.0 reach +12/−3 km.

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Приведен пример реализации опытного фрагмента кластера обработки геофизических данных в модели облачных технологий. Предложенная архитектура позволила уменьшить время на проведение научных исследований и численное моделирование за счет сокращения сроков реконфигурирования вычислительных ресурсов в соответствии с требованиями экспериментов. В качестве примера апробации решения выбрана задача численного моделирования сферической мантийной конвекции на основе данных сейсмической томографии. Уравнение Стокса решается методом конечных элементов с помощью программного кода CitcomS. Представлены результаты трехмерного моделирования глобальной мантийной конвекции. Расчеты демонстрируют структуру мантийных течений в современной Земле. Под континентами, кроме Восточной Африки, Юго-Восточной и Восточной Азии и Западной Антарктиды, находятся нисходящие мантийные потоки и отрицательные аномалии температуры. Нисходящий мантийный поток под Евразией и восходящий поток под Арктикой толкают Северную Евразию на юг, порождая напряжения в коре и процессы горообразования внутри Евразии. Еще один мощный нисходящий мантийный поток возникает между Америками в Карибской зоне субдукции. Древние кратоны характеризуются холодными областями мантии под ними. Под Восточной Африкой находятся положительная температурная аномалия и восходящий мантийный поток, ответственный за систему рифтов на поверхности африканского континента. Похожая аномалия обнаруживается и в районе Байкальской рифтовой зоны. Глобальный восходящий поток находится под Тихим океаном. We present an example of the realization of a geophysical data processing cluster in a cloud technology model. Cloud technologies can increase the efficiency of computing resources due to their virtualization and ensuring elasticity. The proposed architecture allows reducing the time of numerical modelling by decreasing the time on reconfiguring computing resources in accordance with research requirements. As an example of testing the solution, the problem of numerical modelling of spherical mantle convection based on seismic tomography data was taken. The Stokes equation is solved by the finite element method using CitcomS code. The results of three-dimensional modelling of global mantle convection are presented. Calculations demonstrate the structure of mantle flows in modern Earth. Under the continents, with the exception of East Africa, Southeast and East Asia and West Antarctica, there are downward mantle flows and negative temperature anomalies. The descending mantle flow under Eurasia and the ascending flow under the Arctic push North Eurasia to the south, is causing stresses in the crust and orogenic processes within Eurasia. Another powerful downward mantle flow occurs between North and South America in the Caribbean subduction zone. Ancient cratons are characterized by cold regions in the mantle beneath them. Under East Africa, there is a positive temperature anomaly and an upward mantle flow, responsible for the East African Rift System. A similar anomaly is also found in the Baikal rift zone. A global ascending mantle flow forms under the Pacific Ocean.