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Актуальность исследования обусловлена широким применением геологического моделирования как метода изучения залежей нефти и газа терригенного комплекса пород и палеозойского комплекса. Последний, по сравнению с терригенным, имеет специфическое геологическое строение и является менее изученным, именно поэтому проблемы палеозоя актуальны для всех добывающих компаний и научно-исследовательских институтов. Цель: провести анализ методов геологического моделирования, повышающих уровень достоверности 3D моделей месторождений палеозойского возраста. Объектом исследования являются палеозойские карбонатные нефтепродуктивные отложения. Методы. Рассмотрена возможность и эффективность применения различных методов геологического моделирования карбонатных пород палеозойского возраста, повышающих достоверность моделирования и позволяющих снизить риски не подтверждения прогнозных показателей, на примере Калинового и Северо-Калинового месторождений. Рассмотренные в статье методы 3D моделирования применимы к другим нефтегазовым месторождениям со схожими геологическими особенностями. Результаты. Рассмотрено два подхода к реконструкции залегания слоев в геологической модели палеозойского комплекса (горизонтальное и наклонное), выделены преимущества и недостатки каждого из них. Оценена необходимость и эффективность введения этапа типизации горных пород при моделировании залежей с резко невыдержанными по площади фильтрационно-емкостными свойствами. На примере Северо-Калинового месторождения показано, что применение описанных в статье методов моделирования приводит к повышению достоверности 3D геологической модели, что в свою очередь оказывает влияние на показатели технологического и экономического извлечения нефти из объектов доюрского комплекса. The relevance of the research is caused by the widespread use of geological modeling as a method for studying oil and gas deposits of the terrigenous rock complex and the Paleozoic ones. The Paleozoic complex, in comparison with the terrigenous one, has a specific geological structure and is less researched, therefore the problems of the Paleozoic are relevant for all mining companies and research institutes. The purpose of the research is to analyze methods of geological modeling that increase the level of reliability of 3D models of Paleozoic deposits. The object of the research is the Paleozoic carbonate and fractured oil productive sediments. Methods. The article considers the possibility and effectiveness of applying various methods of geological modeling of Paleozoic carbonate and fractured rocks. The methods increase the reliability of modeling and reduce the risks of not confirming the forecast indicators, using the example of the Kalinovoe and Severo-Kalinovoe deposits. The 3D modeling methods discussed in the article are applicable to other oil and gas fields with similar geological deposits. Results. Two methods of reconstructing the bedding in the geological model of the Paleozoic complex were considered (horizontal and tilted) and the advantages and disadvantages of each of them were highlighted. The necessity and effectiveness of the introduction of the additional stage of rock typification was evaluated for modeling deposits with reservoir properties that are sharply not sustained over the area. On the example of the Severo-Kalinovoe deposit, it is shown that the application of the modeling methods described in the article leads to improve accuracy of the 3D geological model. This affects the increase in the efficiency of technological and economic extraction of hydrocarbons from the objects of the pre-Jurassic complex.

The study evaluates the geothermal energy potential of two depleted oil and gas reservoirs representing two different lithostratigraphic formations—the carbonate formation of the Visean age from the basement of the Carpathian Flysch and the Rotliegend sandstone formation from the Eastern part of the Foresudetic Monocline, Poland. Advanced modeling techniques were employed to analyze the studied formations’ heat, storage, and transport properties. The obtained results were then used to calculate the heat in place (HIP) and evaluate the recoverable heat (Hrec) for both water and CO2 as working fluids, considering a geothermal system lifetime of 50 years. The petrophysical parameters and Hrec were subsequently utilized in the generalized c-means (GFCM) clustering analysis, which helped to identify the plays with the greatest geothermal potential within the studied formations. The central block emerged as the most promising area for the studied carbonate formation. It exhibited significant potential for heat production, with Hrec values of approximately ~4036 and 932 MW when H2O and CO2 were used as working fluids, respectively. The central block has three wells that can be easily adapted for geothermal production. The area, however, may require permeability enhancement techniques to increase reservoir permeability. Two prospective zones were determined for the analyzed Rotliegend sandstone formation: one in the NW region and the other in the SE region. In the NW region, the estimated Hrec was 233,855 MW and 44,018 MW, while in the SE region, it was 257,457 MW and 48,231 MW, using H2O and CO2 as working fluids, respectively. Both areas have high porosity and permeability, providing good storage and transport properties for the working fluid, and abundant wells that can be configured for multiple injection-production systems. When comparing the efficiency of geothermal systems, the water-driven system in the Visean carbonate formation turned out to be over four times more efficient than the CO2-driven one. Furthermore, in the case of the Rotliegend sandstone formation, it was possible to access over five times more heat using water-driven system.

Three-dimensional geological modeling is a process of interpreting geological features from limited sample data and making predictions, which can be converted into a classification task for grid units in the geological space. In sedimentary settings, it is difficult for a single geological classification process to comprehensively express the complex geological spatio-temporal relationships of underground space. In response to this problem, we proposed a progressive geological modeling strategy to reconstruct the subsurface based on a machine learning approach. The modeling work consisted of two-stage classifications. In the first stage, a stratigraphic classifier was built by mapping spatial coordinates into stratigraphic classes, which reflected the geological time information of the geological unit. Then, the obtained stratigraphic class was used as a new feature for the training of the lithologic classifier in the second stage, which allowed the stratigraphic information to be implicitly converted into a new rule condition and enabled us to output the lithologic class with stratigraphic implications. Finally, the joint Shannon entropy of two classifications was calculated to evaluate the uncertainty of the total steps. The experiment built a fine-grained 3D geological model with integrated expression of stratigraphic and lithologic information and validated the effectiveness of the strategy. Moreover, compared with the conventionally trained classifier, the misclassification of the lithologic class between different strata in the progressive classification results has been reduced, with the improvement of the F1-score from 0.75 to 0.78.

The article is devoted to the urgent problem of studying the features of the properties of poorly studied oils at great depths (more than 4,500 m), the need for development of which is caused by a reduction in oil production in traditional oil producing provinces. A study was made of changes in the physicochemical properties and occurrence conditions of oils depending on the depth, which made it possible to clarify the quantitative patterns of changes in the physicochemical properties of oils at different depths and to reveal features of the properties of poorly studied deep-seated oils. The studies used information on 21067 oil samples from 167 oil-bearing basins of the world, obtained from the database on the physicochemical properties of oils. It has been shown that in different oil-bearing basins the density and viscosity of oils decreases with depth. The content of sulfur, resins and asphaltenes also decreases with depth, and the content of light fractions and oil gas increases. The paraffin content increases to a depth of 3-4 km, and then decreases with increasing depth. The features of the physicochemical properties of deep-seated oils have been established, which are manifested in a decrease in the density and viscosity of oils, in a decrease in the content of sulfur and asphalt-resinous substances, and in an increase in the content of light fractions and oil gas. The results of geological modeling of changes in the stress state of rocks associated with the displacement of the foundation blocks due to tectonic processes are considered. It has been shown that at the edges of the downing tectonic blocks at the boundary of the sedimentary cover and the basement, zones of minimum pressure (decompression zones) are formed. The lightest hydrocarbons migrate along the faults into the decompression zones, forming deep-seated hydrocarbon deposits, what can serve as a justification for the features of the properties of deep-seated oils established in the work.

To improve the efficiency and accuracy of carbonate reservoir research, a unified reservoir knowledge base linking geological knowledge management with reservoir research is proposed. The reservoir knowledge base serves high-quality analysis, evaluation, description and geological modeling of reservoirs. The knowledge framework is divided into three categories: technical service standard, technical research method and professional knowledge and cases related to geological objects. In order to build a knowledge base, first of all, it is necessary to form a knowledge classification system and knowledge description standards; secondly, to sort out theoretical understandings and various technical methods for different geologic objects and work out a technical service standard package according to the technical standard; thirdly, to collect typical outcrop and reservoir cases, constantly expand the content of the knowledge base through systematic extraction, sorting and saving, and construct professional knowledge about geological objects. Through the use of encyclopedia based collaborative editing architecture, knowledge construction and sharing can be realized. Geological objects and related attribute parameters can be automatically extracted by using natural language processing (NLP) technology, and outcrop data can be collected by using modern fine measurement technology, to enhance the efficiency of knowledge acquisition, extraction and sorting. In this paper, the geological modeling of fracture-cavity reservoir in the Tarim Basin is taken as an example to illustrate the construction of knowledge base of carbonate reservoir and its application in geological modeling of fracture-cavity carbonate reservoir.

The quality and production of shale gas are directly dependent on the development of fractures. Especially in large-scale fracturing development, natural and hydraulic fractures play significant roles. Consequently, there is a growing demand for the quantitative characterization of shale gas reservoir fractures and the development of geological modeling technology. Structured and non-structural fractures make up mainly of natural fractures in shale gas reservoirs. External factors such as tectonic stress control the former, while internal factors such as rock and mineral composition control the latter. Fractures of different scales have a variety of primarykey characterization parameters and prediction techniques. Natural fracture models for shale gas reservoirs are predominant on large-scale and mesoscale fractures. In the numerical simulation, hydraulic fracture modeling is explored in greater detail. This paper discusses the design and explains the main directions of natural and hydraulic fracture modeling in shale gas reservoirs from the aspects of the multi-information application, multi-technology integration, and multi-disciplinary crossing considering the current and potential technology and production requirements. Natural fractures require fusion characterization and modeling on a multi-scale and multi-method basis. Hydraulic fracturing necessarily involves the fusion of multiple information constraints of forwarding and inverse simulation. Furthermore, using the principle of geology-engineering integrated modeling, this paper describes the inner relationship and development of the geological model of a shale gas reservoir from three aspects of model type, data integration, and model fusion to guide the efficient development of shale gas reservoirs.

Актуальность исследования обусловлена необходимостью повышения точности прогнозирования технологических показателей разработки месторождений углеводородного сырья. Это позволит подбирать оптимальное оборудование для подготовки сырья, сдвигать сроки ввода промышленных мощностей для достижения максимального экономического эффекта от разработки месторождений. Цель: определить точность расчета коэффициента пористости месторождения, принятую при подсчете запасов и проектировании разработки; оценить вариации коэффициента пористости во всем объеме месторождения; оценить степень снижения точности определения коэффициента пористости при переходе от этапа керновых исследований до трехмерной геологической модели; установить причины снижения точности определения коэффициента пористости при трехмерном геологическом моделировании. Объекты: сеноманская залежь нефтегазоконденсатного месторождения на севере Западной Сибири. Методы: вариограммный анализ, трехмерное геологическое моделирование, оценка точности определения коэффициента пористости. Результаты. Для корректного выполнения подсчета запасов и подготовки проектного документа требуется определить коэффициент пористости с погрешностью не более 5 %. В работе оценена вероятность достижения требуемого уровня точности расчета коэффициента пористости при подсчете запасов только по данным геофизических исследований скважин, по результатам данных геофизических исследований скважин, но с учетом расположения скважин по площади месторождения, а также с учетом пространственного распространения коэффициента пористости. Выполнена оценка границ изменения коэффициента пористости по всему объему породы-коллектора, что в дальнейшем может послужить основой для адаптации гидродинамической модели. Рассчитано снижение соотношения объемов исследованного керна к объему породы по геофизическим исследованием скважины, к общему объему породы-коллектора, а также проведена оценка точности определения коэффициента пористости при переходе от лабораторных исследований к среднему коэффициенту пористости по всему объему породы-коллектора. The relevance of the study is caused by the need to improve the accuracy of forecasting technological indicators of development of hydrocarbon deposits. This will allow us to select the optimal equipment for preparation of raw materials, to shift the timing of commissioning of industrial capacities, to achieve the maximum economic effect from the development of deposits. The aim of the research is to determine the accuracy of calculation of the porosity coefficient of the field, adopted in the calculation of reserves and design development; to estimate the variation of the porosity coefficient in the entire volume of the deposit; to assess the degree of decrease in the accuracy of determining the porosity coefficient during the transition from the stage of core studies to a threedimensional geological model; to establish the reasons of decrease in accuracy of determination of porosity coefficient at threedimensional geological modeling. Object: Cenomanian reservoir oil and gas condensate field located in the North of Western Siberia. Methods: variogram analysis, three-dimensional geological modeling, estimation of porosity coefficient determination accuracy. Results. For correct calculation of stocks and preparation of the project document it is required to define porosity coefficient with an error no more than 5 %. The authors have estimated the probability of achieving the required level of accuracy in calculation of porosity when assessing the reserves only according to geophysical researches of wells, the results of geophysical researches of wells data, but given the location of wells in the field area and also taking into account the spatial distribution of porosity. The boundaries of the porosity coefficient change in the entire volume of the deposit were estimated. This can serve as a basis for adaptation of the hydrodynamic model in the future. The ratio of the volume of the studied core to the volume of the studied geophysical researches of wells rock to the total volume of the reservoir rock is calculated, and the accuracy of determining the porosity coefficient during the transition from laboratory studies to the average porosity coefficient in the field volume is estimated.

An orthogonal 2D training image is constructed from the geological analysis results of well logs and sedimentary facies; the 2D probabilities in three directions are obtained through linear pooling method and then aggregated by the logarithmic linear pooling to determine the 3D multi-point pattern probabilities at the unknown points, to realize the reconstruction of a 3D model from 2D cross-section. To solve the problems of reducing pattern variability in the 2D training image and increasing sampling uncertainty, an adaptive spatial sampling method is introduced, and an iterative simulation strategy is adopted, in which sample points from the region with higher reliability of the previous simulation results are extracted to be additional condition points in the following simulation to improve the pattern probability sampling stability. The comparison of lateral accretion layer conceptual models shows that the reconstructing algorithm using self-adaptive spatial sampling can improve the accuracy of pattern sampling and rationality of spatial structure characteristics, and accurately reflect the morphology and distribution pattern of the lateral accretion layer. Application of the method in reconstructing the meandering river reservoir of the Cretaceous McMurray Formation in Canada shows that the new method can accurately reproduce the shape, spatial distribution pattern and development features of complex lateral accretion layers in the meandering river reservoir under tide effect. The test by sparse wells shows that the simulation accuracy is above 85%, and the coincidence rate of interpretation and prediction results of newly drilled horizontal wells is up to 80%.

The relevance of the study is caused by the need to improve the accuracy of forecasting technological indicators of development of hydrocarbon deposits. This will allow us to select the optimal equipment for preparation of raw materials, to shift the timing of commissioning of industrial capacities, to achieve the maximum economic effect from the development of deposits. The aim of the research is to determine the accuracy of calculation of the porosity coefficient of the field, adopted in the calculation of reserves and design development; to estimate the variation of the porosity coefficient in the entire volume of the deposit; to assess the degree of decrease in the accuracy of determining the porosity coefficient during the transition from the stage of core studies to a three-dimensional geological model; to establish the reasons of decrease in accuracy of determination of porosity coefficient at three-dimensional geological modeling. Object: Cenomanian reservoir oil and gas condensate field located in the North of Western Siberia. Methods: variogram analysis, three-dimensional geological modeling, estimation of porosity coefficient determination accuracy. Results. For correct calculation of stocks and preparation of the project document it is required to define porosity coefficient with an error no more than 5 %. The authors have estimated the probability of achieving the required level of accuracy in calculation of porosity when assessing the reserves only according to geophysical researches of wells, the results of geophysical researches of wells data, but given the location of wells in the field area and also taking into account the spatial distribution of porosity. The boundaries of the porosity coefficient change in the entire volume of the deposit were estimated. This can serve as a basis for adaptation of the hydrodynamic model in the future. The ratio of the volume of the studied core to the volume of the studied geophysical researches of wells rock to the total volume of the reservoir rock is calculated, and the accuracy of determining the porosity coefficient during the transition from laboratory studies to the average porosity coefficient in the field volume is estimated.

Lignite production in Greece is implemented mainly by the Public Power Corporation (PPC), with the higher production being in the Lignite Center of Western Macedonia. A continuous surface mining method is used in order to satisfy the high production needs combined with the necessity for selective mining; however, the occasional appearance of hard rock formations in the South Field mine overburdens was critical for the adoption of a discontinuous auxiliary method of rock mass removal, at these places, by explosives and large shovels. Furthermore, to minimize the delay of changing the machinery arrangements when a hard rock formation is met, an a priori knowledge of the spatial distribution of these rock masses would be catalytic. In this work, a plurigaussian simulation model of the overburden geological formations is developed in the South Field mine. This model could be used as a guide to schedule and optimize the overburden removal process. Validation of the model was affected in two ways: by direct comparing estimated to real cross-sections as observed on mine slopes or by correlating PPC’s recorded volumetric results to the average simulated hard rock percentages.

This paper presents a surface modeling method for interpolating orebody models based on a set of cross-contour polylines (geological polylines interpreted from the raw geological sampling data) using the bi-Coons surface interpolation method. The method is particularly applicable to geological data with cross-contour polylines acquired during the geological and exploration processes. The innovation of this paper is that the proposed method can automatically divide the closed loops and automatically combine the sub-meshes. The method solves the problem that it is difficult to divide closed loops from the cross-contour polylines with complex shapes, and it greatly improves the efficiency of modeling based on complex cross-contour polylines. It consists of three stages: (1) Divide closed loops using approximate planes of contour polylines; each loop is viewed as a polygon combined with several polylines, that is the n-sided region. (2) After processing the formed n-sided regions, Coons surface interpolation is improved to complete the modeling of every single loop (3) Combine all sub-meshes to form a complete orebody model. The corresponding algorithm was implemented using the C++ programing language on 3D modeling software. Experimental results show that the proposed orebody modeling method is useful for efficiently recovering complex orebody models from a set of cross-contour polylines.

In order to maximize the resource utilization rate, it is common to adopt one-time overall deployment of well pattern to develop shale gas, and the design of horizontal well spacing is the key to the deployment of shale gas well pattern. To determine the optimal well spacing, it is not only necessary to understand both geological characteristics and drilling fracturing technology, but also take into consideration the influences of economic factors, such as gas price and cost. At present, there is no reliable method for designing the well spacing of shale-gas horizontal wells at home and abroad. In this paper, a method for analyzing the well spacing of shale-gas horizontal wells based on the integration of geology, engineering and economy was established for the first time. Then, by means of geological modeling, numerical simulation and cash flow analysis, the well spacing of shale-gas development wells in Well Block Ning 209 in the Changning–Weiyuan National Shale Gas Demonstration Area in the Sichuan Basin was comprehensively evaluated by using estimated ultimate reserve (EUR), recovery factor and internal rate of return (IRR). And the following research results were obtained. First, under the current geological, engineering and economic conditions of Well Block Ning 209, the IRR of shale gas platform development can be kept greater than 8% if the well spacing is larger than 240 m. Second, when the well spacing is controlled between 330 m and 380 m, single well EUR, recovery rate of the platform and economic benefit can be considered simultaneously. In conclusion, the research results support the formulation of the shale gas development technology policy of Well Block Ning 209 and lay a foundation for the realization of its scale efficient development of shale gas.

A three-dimensional stratum model stratum model is a useful auxiliary tool for geotechnical engineering and other exploration work. The existing methods for stratum model construction lack complete topological descriptions of entities, so it is difficult to apply them to 3D geological modeling with complex geometric structures and complex topological relationships between modules. To solve the above problem, in this paper, the boundary representation method is used to represent the arbitrarily-shaped geological entities, and the half winged-edge-face structure topological structure is proposed to describe the topological information of the stratum model for a complex entity. The topological structure can record the topological information of the solid stratum model completely, thereby providing the basis for operations with the model and the applications of various algorithms. Based on this topological structure, the construction process for a 3D solid stratum model is proposed. The reliability and effectiveness of the constructed 3D solid stratum model are verified by an engineering case. The solid stratum model not only solves the geological modeling problem with respect to complex geometric and topological relations, but also provides a new method and idea for 3D geological modeling.

As a special type of fracture-cavity carbonate reservoir, fault/fracture-controlled paleokarsts are affected by large strike-slip faults with various storage spaces, irregular geometry, and stochastic spatial distribution, which brings new challenges to their 3D quantitative characterization and geological modeling. Based on multi-scale research data, a hierarchical scheme of a fault-controlled paleokarst is established for the Tahe oilfield, and then a hierarchical modeling method for the paleokarst is proposed based on the principles of hierarchical constraint and genetic control. The results show that the fault-controlled paleokarst hierarchy is divided into four levels according to genesis and scale. These are the strike-slip fault impact zone, the fault-controlled external paleokarst envelope, the fault-controlled internal paleokarst architecture, and the internal karst cave fillings. The strike-slip fault impact zone model is established using deterministic data of the main fault, secondary fault, envelope range, and key geological horizons obtained from seismic interpretation. Based on the seismic FL (Fault Likelihood) attribute, the external envelope model of the fault-controlled paleokarst is established using the deterministic method through automatic attribute segmentation and drilling calibration. With the constraint of the external envelope, the internal architectural elements are classified and modeled. A large-scale karst cave model and mesoscale discrete fracture distribution model are established using the deterministic method based on the seismic texture property and seismic ant property truncation. Taking well data as conditional data and seismic-geological probability cubes as constraint data, the sequential indication simulation and object-based marked point process simulation methods are used to obtain the model of the dissolution pores distribution and the model of the discrete small-scale fractures distribution, respectively. Finally, a typical fault-controlled paleokarst reservoir in the TP area of the Tahe oilfield is taken as an example to test the above modeling method; the 3D integrated model developed in this study can reflect the spatial hierarchy of the fault-controlled paleokarst carbonate reservoir.

В статье рассматривается комплексный подход к проведению многовариантных расчетов (МВР) с использованием автоматизированной системы построения моделей, при котором происходит одновременное варьирование геологических и гидродинамических параметров неопределенности. Авторами разработан скрипт построения моделей (workflow), позволяющий в рамках единого цикла генерировать различные варианты геолого-гидродинамических моделей. На примере газового месторождения Западной Сибири проведена оценка потенциальных уровней добычи углеводородов (УВ). Выявлены ключевые неопределенности, влияющие на накопленную добычу и начальные запасы. Построено дерево принятия решений по разработке месторождения. Использование комплексного подхода позволило учесть большее количество параметров неопределенности, значительно сократить машинное время, уменьшить влияние человеческого фактора и число рутинных операций., This study reviews an integrated approach to multivariate hydrodynamic simulations based on simultaneous variation of geological and hydrodynamic uncertainties. A workflow capable of generating various realizations of models within a single cycle is developed. As a practical example, an assessment of hydrocarbon production levels for a gas field in Western Siberia was carried out, identifying key uncertainties that affect cumulative gas production and original gas in-place volume. A decision tree for gas field development is designed. An integrated approach allowed the researchers to analyze more uncertainties, shorten calculation time and reduce the influence of the human factor as well as number of routine operations.

В статье рассмотрены полевые материалы структурного бурения скважин в пределах восточного борта Мелекесской впадины (МВ) и западного склона Южно-Татарского свода (ЮТС). По данным каротажа, кернового материала и структурных карт поверхности сакмарского резервуара построены литологическая карта и трехмерная модель поверхности сакмарского природного резервуара, а также обоснованы перспективы битумоносности в пределах изученных тектонических элементов на основании вновь построенных карт и модели., This article considers materials of structural drilling of wells within the eastern side of the Melekess depression (MD) and the western slope of the South Tatar Arch (STA). According to the data of logging, core material and structural maps of the surface Sakmarian reservoir, a lithological map and a three-dimensional model of the surface of the Sakmarian natural reservoir were constructed, and the prospects of bituminosity within the studied tectonic elements were substantiated on the basis of newly constructed maps and models.

The Itataia phosphate-uranium deposit is located in the northwest segment of the Borborema Province in the Ceará Central Domain. The ore mineral is uranium-enriched microcrystalline collophanite apatite that occurs in massive bodies and lenses, stockworks, as well as hydrothermal and karst breccias associated with marble, calc-silicate rocks and gneisses of the Itataia Group. The deformational history of the deposit includes ductile structures developed in the final stages of thrust tectonics linked to the Brasilian orogeny and later brittle phases related to extensional tectonics, which influenced phosphorus and uranium remobilization and the formation of ore bodies. The main uranium anomaly coincides with the upper part of the Serrote da Igreja hill, bordered to the north by an E-W trending subvertical fault scarp that controls a wide valley. Geometric modeling of the geological data of the deposit provides a three-dimensional view of the geometry of ore bodies, distribution of host rock and faults that propagate beneath the surface and control mineralization, as well as the upper and lower limits of surface weathering. The three-dimensional geometric model using the GoCAD software served as a powerful tool for the analysis of the geology of the Itataia deposit, highlighting the geometry of rocks and ore bodies and the processes involved in the genesis of phosphate-uranium mineralization.

Orientadores: Alessandro Batezelli, Ana Clara Braga de Souza Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências Resumo: A Sub-bacia Mundaú é a única região produtora de hidrocarbonetos offshore da Bacia do Ceará, localizada na Margem Equatorial do Brasil. A origem e evolução da Sub-Bacia Mundaú é consequência da ruptura do supercontinente Pangea, no Cretáceo Inferior, que levou à abertura e desenvolvimento do Oceano Atlântico Equatorial. Esta área é considerada uma nova fronteira de exploração, onde algumas pesquisas foram desenvolvidas nos últimos anos. No entanto, as interações entre os eventos transtensivos e distribuições espaço-temporais de subsidência tectônica são pouco conhecidas. Para entender estes eventos, 57 poços e aproximadamente 5.800 km de linhas sísmicas 2D foram analisados. A partir desses dados, foram realizadas interpretações estratigráficas e estruturais ao longo de toda a sub-bacia, possibilitando a construção de 43 pseudopoços. Através da descompactação dos poços e pseudopoços, pelo método de backstripping, foi possível reconstruir sete fases tectônicas da bacia, referente a sequência rifte (RP01, RP02 e RP03), a sequência de transição (BP01) e sequência drifte (DP01, DP02 e DP03). Também foram analisados os conjuntos de falhas presentes em três zonas (Zona Oeste, Leste e Central) propostas nesse trabalho. Estruturalmente, a sub-bacia apresenta quatro famílias de falhas, agrupadas em dois conjuntos ortogonais, formadas em dois eventos distintos. O primeiro evento formou falhas R e P, orientadas a NWW-SEE e NNE-SSW, respectivamente, considerando o Modelo de Riedel. Enquanto, o segundo evento formou falhas R e P, orientadas a NNWSSE e NEE-SWW, respectivamente. Através da reconstrução tectônica, foi observado a formação diacrônica de dois depocentros, inicialmente na Zona Oeste (ZO) durante a RP01, seguido por nova formação na Zona Central (ZC) durante a RP02. Apesar da intensa atividade tectônica em ZO e ZC, a Zona Leste (ZL) apresentou baixas taxas de subsidência e pouco desenvolvimento durante toda a fase rifte. Por sua vez, a BP01 apresentou aumento das taxas de subsidência, comparado com a RP03, indicando a influência tectônica ainda durante a fase transicional. Por fim, a fase drifte apresentou as menores taxas de subsidência, espacialmente distribuídas em padrão oposto a fase rifte. A partir dos resultados, foi identificado a rotação da Principal Zona de Deslocamento (PZD), com movimentação inicialmente paralela, formando o depocentro da ZO e a primeira geração de falhas, durante RP01. Após a RP02 a movimentação foi oblíqua, formando o segundo depocentro na ZC e uma segunda geração de falhas. Em adição, foi identificado significativo controle termal durante a fase drifte, associado principalmente eventos magmáticos. Este estudo descreve as principais estruturas formadas ao longo de um deslocamento paralelo e oblíquo da PZD,sobrepostos em uma mesma bacia, sendo um dos poucos exemplos naturais descritos até o momento Abstract: The Mundaú Sub-basin is the only offshore hydrocarbon-producing region of the Ceará Basin, located at the Equatorial Margin of Brazil. The origin and evolution of the Mundaú Sub-basin are a consequence of the rupture of the Pangea supercontinent during the Lower Cretaceous, which led to the opening and development of the Equatorial Atlantic Ocean. This area is considered a new exploration frontier, where some research has been developed in recent years. However, the interactions between transtensive events and spatio-temporal distributions of tectonic subsidence are poorly known. To understand these events, fifty-seven wells and approximately 5,800 km of 2D seismic lines were analyzed. From these data, stratigraphic and structural interpretations were performed throughout the sub-basin, enabling the construction of 43 pseudo wells. Through the decompression of the wells and pseudo wells by the backstripping method, it was possible to reconstruct seven tectonic phases of the basin, referring to the rift sequence (RP01, RP02, and RP03), the transition sequence (BP01), and the drift sequence (DP01, DP02, and DP03). The fault sets present in three zones (West, East, and Central Zone) proposed in this work were also analyzed. Structurally, the sub-basin presents four families of faults, grouped into two orthogonal sets, formed in two different events. The first event formed R and P faults, oriented NWW-SEE and NNESSW, respectively, considering the Riedel Model. Moreover, a second event formed R and P faults, oriented at NNW-SSE and NEE-SWW, respectively. The diachronic formation of two depocenters was observed through tectonic reconstruction, initially in the West Zone (WZ) during RP01, followed by a new formation in the Central Zone (CZ) during RP02. Despite the intense tectonic activity in WZ and CZ, the East Zone (EZ) showed low subsidence rates and little development during the entire rift phase. In turn, BP01 showed increased subsidence rates than RP03, indicating tectonic influence still during the transitional phase. Finally, the drift phase showed the lowest subsidence rates, spatially distributed in an opposite pattern to the rift phase. From the results, a rotation of the Principal Displacement Zone (PDZ) was identified, with initially parallel motion, forming the depocentre of the WZ and the first fault generation during RP01. After RP02, the movement was oblique, forming the second depocentre in the CZ and the second generation of faults. In addition, significant thermal control was identified during the drift phase, mainly associated with magmatic events. This study describes the main structuresformed along with a parallel and oblique PDZ displacement, overlapping in the same basin, one of the few natural examples described Mestrado Geologia e Recursos Naturais Mestre em Geociências CAPES 001

В статье представлен подход к моделированию низкопроницаемых, низкосвязанных зон глубоководной фации конусов выноса на примере одного из лицензионных участков Приобского месторождения, характеризующегося высокими темпами падения продуктивности скважин после запуска из бурения. На рассматриваемом участке бурение большого количества горизонтальных скважин (ГС) позволило провести измерение среднего размера песчаных тел. В ходе проведенного исследования установлено, что средний размер тел составляет 220 м. На этапе гидродинамического моделирования получена лучшая сходимость продуктивности скважин в динамике, чем при стандартном подходе к построению модели., The article presents an approach to modeling low-permeability, low-dissected zones of deep-water fan facies on the example of one of the licensed areas of the Priobskoye field, based on a significant reduction in correlation radii. Drilling of many horizontal wells (HWs) in the area under consideration made it possible to measure the average size of sand bodies. For a more reliable result, horizontal wells (HWs) were taken at an enormous distance from each other and from different parts of the field. The trajectory of the horizontal part of the wells penetrates parallel to the structural surfaces. In the study’s course, it is deemed that the average size of the bodies is 220 m. At the stage of hydrodynamic modeling, a better convergence of well productivity dynamics was obtained than with the standard approach to building a model.

Geothermal power plants have become the main application that utilizes geothermal energy. The utilization of deep geothermal energy adheres great importance to the soil condition. One of the biggest challenges faced by geothermal power plant designers is to reduce the risk of soil exploration. To solve this problem, forecasting by modeling has proven to be an important tool to address the problem. In this research, a geo-model was established by modeling three geological layers with different hydraulic and thermal properties to solve the above dilemma. The layers, elevation, and fault zones were simulated using interpolation functions from an artificial dataset. The coupled porous media flow and heat transfer problem using Darcy’s law, as well as heat transfer in porous media interfaces, were studied. The evolution of the flow field, hydrothermal performance, and temperature gradient were also analyzed for a period of 10 years. The results showed the recoverable thermal energy area gradually moved downwards during the 10-year simulation time. When the distance between the recharge well and the production well exceeded 200 m, the collection efficiency was significantly decreased. After 5 years of extraction, the power generation efficiency of the heat source will be less than 9.75%. These results effectively avoided the exploration cost of geothermal power plant site selection, which is significant for the efficiency improvement of geothermal energy.

In this paper, to update the orebody model based on the given interpreted geological information, we present a local dynamic updating method of the orebody model that allows the interactive construction of the constraint deformation conditions and the dynamic updating of the mesh model. The rules for constructing deformation constraints based on the control polylines are discussed. Because only part of the model is updated, the updated mesh is effective and the overall quality is satisfactory. Our main contribution is that we propose a local dynamic updating method for the orebody model based on mesh reconstruction and mesh deformation. This method can automatically update a given 3D orebody model based on a set of unordered geological interpretation lines. Moreover, we implement a deformation neighborhood region search method based on the specified ring radius and a local constrained mesh deformation algorithm for the orebody model. Finally, we test the method and show the model update results with real geological datasets, which proves that this method is effective for the local updating of orebody models.

In this paper, we present a multi-domain implicit surface reconstruction algorithm for geological modeling based on the labeling of voxel points. The improved algorithm sets a label for each voxel point to represent the type of its geological domain and then obtains all the voxel points in the void areas. After that, the improved algorithm modifies the labels of the voxel points in the void areas and finally reconstructs the geological models through the Multiple Material Marching Cubes (M3C) algorithm. The improved algorithm solves the problems of some unexpected overlaps and voids in geological modeling by setting and modifying the labels of the voxel points. Our key contribution is proposing a labeling processing method to repair the overlap and void defects generated in the geological modeling and realizing the improved M3C algorithm. The experimental results of some geological models show the performance of the improved method. Compared with the original method, the improved method can repair the overlap and void defects in geological modeling to ensure the raw structural adjacency relationships of the geological bodies.

In the process of 3D modeling of geological body with fault, it is the primary problem to calculate the intersecting line between fault plane and various geological models. To quickly locate geological models intersecting fault planes, this paper adopts the algorithm of intersection detection of hybrid bounding boxes. Firstly, the principal component analysis is used to generate the bounding box of the tightly bounding geological model. Then, based on the separation axis theorem, an improved algorithm is proposed to realize the intersection detection of hybrid bounding boxes, which effectively reduces the number of detection and improves the efficiency. Experimental results show that this algorithm can greatly shorten the time of intersection test, and improve the efficiency of intersection calculation. This paper provides an algorithm basis for quickly locating the geological model cut by fault plane.

The study focuses on building a 3D-dimensional model for using well log data of 3 wells to enable a better understanding of the reservoir characteristics and evaluation of the hydrocarbon potential in the field of Ronier in the Bongor Basin, Chad. These data are used to build a Lithofacies model, property model, the permeability model and the saturation model which are the parameters that describe the reservoir. Indeed, the accuracy to quantify the geological reserve of Ronier 4 reservoir block depends on the estimation of these values. The result of geological modeling and upscaling of the Ronier 4 block of Ronier oilfield is presented systematically. In this work, a Sequential Gaussian Simulation (SGS) algorithm under the phase control based on the collocated co-Kriging is adopted and the models of porosity, permeability and saturation are established. Lithofacies model has sand (0) content of 66.69% mostly the first layer, while the code (2) shale content 12.15% mostly concentrated in the center, north and south. Finally, the code (3) sand content is 21.16%. The NTG distribution is highly concentrated in the north, center and south (1) and 0.7 on average, while the lowest range is 0.1. The study shows a good permeability range between 460 to 1200 and 500 mD on average. The porosity distribution mainly distributed between 17 to 27 and 19% on average. These indicate that it has good reservoir properties. The 3D developed geological model provides the basis for calculating the Oil Initially in Place (OIIP) volumes of hydrocarbons.

Orientador: Armando Zaupa Remacre Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica e Instituto de Geociencias Resumo: Uma modelagem geológica consistente é necessária para que se possa avaliar os reservatórios de petróleo. No caso de campos maduros, existe uma expressiva quantidade de óleo remanescente e, muitas vezes, com boa capacidade de ser recuperado. Para tanto, faz-se uso de técnicas geoestatísticas para construção de modelos sólidos que permitam localizar e quantificar essas acumulações de óleo. Sabe-se que no estudo de caracterização de reservatórios a modelagem litológica é uma etapa essencial, pois ela servirá de base e guiará a modelagem das propriedades petrofisicas. Neste trabalho, propõe-se verificar o impacto na modelagem litológica, mais especificamente no volume de fácies reservatórios, utilizando-se determinados algoritmos de simulação estocástica, como: simulação seqüencial indicatriz, simulação gaussiana truncada e simulação plurigaussiana. O estudo englobou desde a etapa de tratamento de dados, com o processo de mudança de suporte, até o estudo de conectividade das fácies reservatório, por meio do algoritmo de Hoshen-Kopelman. Como resultado, foi possível observar que o algoritmo de simulação plurigaussiana mostrou-se com melhor capacidade de reproduzir as características iniciais do reservatório pelo fato de condicionar os resultados à proporção dos litotipos, matriz de proporção da área e regra de litologia, diferente do algoritmo de simulação seqüencial indicatriz que leva em consideração somente a proporção de fácies, igualmente distribuída para toda a zona do reservatório. Observou-se ainda que o algoritmo de simulação Gaussiano truncado, da maneira que foi implementado no programa utilizado, não traria resultados condizentes com os dados originais Abstract: A consistent geologic modeling is necessary to evaluate the petroleum reservoirs. In mature field, a large amount of remaining oil exists and, many times, with good capacity of being recovered. For this, geostatistical techniques are used for construction of solid models that allow to locate and to quantify this remaining oil. In a reservoir characterization study, the lithologic modeling is an essential stage because it will be the basis to the petrophysical properties modeling. This thesis proposes evaluate the proportionate impact for the algorithms of stochastic simulation (sequential indicator simulation, truncated gaussian simulation and plurigaussian simulation) in the reservoirs characterization, more specifically, in the volume of reservoir facies. The study passed through the handling data stage, with the upscaling process, until the connectivity study ofthe reservoir facies with the Hoshen-Kopelman algorithm. As results, it was possible to note that the plurigaussian simulation algorithm presented better capacity to reproduce the initial reservoir characteristics because it respect the lithofacies proportion, proportion matrix and the lithotype rule, different of sequential indicator simulation algorithm that takes in consideration only the facies proportion, equally distributed for all reservoir zones. It was still observed that the truncated gaussian simulation algorithm, in the way that it was implemented in the used software, wouldn't bring suitable results with the analyzed data Mestrado Reservatórios e Gestão Mestre em Ciências e Engenharia de Petróleo

The effect of geological modeling largely depends on the normal estimation results of geological sampling points. However, due to the sparse and uneven characteristics of geological sampling points, the results of normal estimation have great uncertainty. This paper proposes a geological modeling method based on the dynamic normal estimation of sparse point clouds. The improved method consists of three stages: (1) using an improved local plane fitting method to estimate the normals of the point clouds, (2) using an improved minimum spanning tree method to redirect the normals of the point clouds, (3) using an implicit function to construct a geological model. The innovation of this method is an iterative estimation of the point cloud normal. The geological engineer adjusts the normal direction of some point clouds according to the geological law, and then the method uses these correct point cloud normals as a reference to estimate the normals of all point clouds. By continuously repeating the iterative process, the normal estimation result will be more accurate. Experimental results show that compared with the original method, the improved method is more suitable for the normal estimation of sparse point clouds by adjusting normals, according to prior knowledge, dynamically.

[eng] This thesis uses different variants of geomechanical modelling approaches to investigate stress, strain and geometry distribution and evolution through time of the Tarfaya salt basin, located on the West African coast. This work has been conducted by geomechanically simulating a sector of the Tarfaya basin containing key features such as diapirs, faults and encasing sediments using 3D and 2D static models and 2D evolutionary models. The 3D and 2D static geomechanical models of the Tarfaya basin system allowed to predict the stresses and strains at present day. Both models are based on present-day basin geometries extracted from seismic data and use a poro-elastic description for the sediments based on calibrated log data and a visco-plastic description for the salt based on values from Avery Island. The models predict a significant horizontal stress reduction in the sediments located at the top of the principal salt structure, the Sandia diapir, consistent with wellbore data. However, the 2D static geomechanical model shows broader areas affected by the stress reduction compared to the 3D model and overestimates its magnitude by less than 1.5 MPa. These results highlight the possibility of using 2D static modelling as a valid approximation to the more complex and time-consuming 3D static models. A more in-depth study of the 2D static model using sensitivity analysis yielded a series of interesting observations: (1) the salt bodies and their geometry have the strongest impact on the final model results; (2) the elastic properties of the sediments do not impact the model results. In other words, the correct definition of the sediments with the highest material contrasts such as salt should be a priority when building static models. Such definition should be ranked ahead of the precise determination of the rheologic parameters for the sediments present in the basin. In this thesis, we also present the results of introducing an evolutionary geomechanical modelling approach to the Tarfaya basin. This study incorporates information of burial history, sea floor geometry and tectonic loads from a sequential kinematic restoration model to geologically constrain the 2D evolutionary geomechanical model. The sediments in the model follow a poro-elastoplastic description and the salt follows a visco-plastic description. The 2D evolutionary model predicts a similar Sandia diapir evolution when compared to the kinematic restoration. This proves this approach can offer a significant advance in the study of the basin, by not only providing the stress and strain distribution and salt geometry at present day, but also reproducing their evolution during the Tarfaya basin history. Sensitivity analysis on the evolutionary model indicates that temporal and spatial variation in sedimentation rate is a key control on the kinematic structural evolution of the salt system. The variation of sedimentation rates in the model controls whether the modelled salt body gets buried by Tertiary sediments (after a continuous growth during the Jurassic and Cretaceous periods) or is able to remain active until the present day. Also, the imposed shortening affects the final stress distribution of the sediments at the present day. To conclude, the results obtained during this study allowed us to understand the formation and evolution of the diapirs in the Tarfaya basin using carefully built geomechanical models. The study demonstrates that carefully built 2D static models can provide information comparable to the 3D models, but without the time and computational power requirements of the 3D models. That makes the 2D approach very appropriate for the exploration stages of a particular prospect. If carefully built, such 2D models can approximate and yield useful information, even from complex 3D structures such as the Tarfaya basin salt structures. This thesis also concludes that incorporating kinematic restoration data into 2D evolutionary models provides insights into the key parameters controlling the evolution of the studied system. Furthermore, it enables more realistic geomechanical models, which, in turn, provide more insights into sediment stress and porosity.

В процессе разработки массивных газовых залежей неизбежен процесс подъема газо-водяного контакта (ГВК), который ведет к обводнению скважин и падению суточной добычи газа. Бурение боковых горизонтальных стволов и новых горизонтальных скважин позволяет поддерживать добычу на проектном уровне. Направление бурения горизонтального участка скважины в значительной степени определяет ее эффективность. В сложных геологических условиях детальный анализ данных сейсмики в районе бурения позволяет снизить риски бурения и достичь плановых запускных показателей. Учет сейсмических данных в геологических моделях зачастую ограничивается низким коэффициентом корреляции между фильтрационно-емкостными свойствами, полученными по скважинам, и сейсмическими атрибутами. В гидродинамических моделях данные сейсмики используются с учетом допущений, принятых инженерами-геологами., The process of raising the gas-water contact (GWC) is inevitable during development of the reservoir. This leads to flodding of wells and reducing of daily gas production. Horizontal sidetracks and new horizontal drilling allows to maintain production at the required level. Mostly, the direction of the horizontal section of the well determines its efficiency. In difficult geological conditions, a detailed analysis of seismic data in the drilling area allows to reduce drilling risks and achieve planned starting rates. Accounting of seismic data in geological models is often limited by a low correlation coefficient between reservoir properties obtained from wells and seismic attributes. Simulation models use seismic data based on the assumptions made by the geological engineers.

Previamente à avaliação técnica e financeira de depósitos minerais, as propriedades geológicas que influenciam na mineralização devem estar entendidas e espacialmente representadas. Tradicionalmente, a modelagem de corpos de minério é feita pela interpolação de contatos manualmente interpretados a partir de seções. Mais recentemente, softwares dedicados vêm disponibilizando rotinas semiautomáticas de modelagem implícita. Embora permitam modelagem mais ágil, modelos implícitos demandam módulos específicos de software e, assim como as técnicas convencionais, os resultados refletem decisões algumas vezes subjetivas do modelador. Esta dissertação propõe a modelagem por probabilidade de indicadores combinada à técnica de anisotropia dinâmica para definir os contornos geológicos de um depósito de ouro cuja mineralização é controlada por fatores estruturais. A partir dos domínios geológicos definidos, a dissertação avalia a aplicabilidade do condicionamento uniforme e condicionamento uniforme localizado na previsão de recursos recuperáveis a partir de uma base de dados exploratória. O estudo compara resultados das técnicas não lineares aos resultados obtidos por krigagem ordinária. Os modelos de recurso obtidos foram reconciliados a cenários de referência simulados a partir do conjunto de dados mais completo disponível no depósito. Em seguida, o nível de sensibilidade dos métodos à configuração amostral foi testado através de estimativas feitas com variados espaçamentos da malha e os resultados reconciliados aos modelos de referência. O modelo probabilístico dos indicadores mostrou ser capaz de reproduzir com qualidade os contornos da mineralização, sobretudo nas regiões com maior disponibilidade de dados. A anisotropia dinâmica permitiu capturar com qualidade os contornos estruturais de macroescala, produzindo pseudo-probabilidades estimadas consistentes com a expectativa geológica. Resultados mostraram que as estimativas obtidas pelas técnicas não lineares reproduziram de forma mais acurada a distribuição de probabilidade e recursos recuperáveis dos modelos de referência. Entretanto, previsões feitas por condicionamento uniforme apresentaram menor eficiência na reprodução local dos teores se comparadas à krigagem ordinária. Prior to resource assessment and mine planning, the geometry and other relevant geological properties of the deposit must be spatially represented through tridimensional models. Traditionally, the modeling process is manually made by interpolating contact lines interpreted from cross-sections. Recently, mining industry has been implementing semi-automatic implicit modeling routines. Although it provides agility to the process, implicit models demand specific software packages and as well as traditional modeling approaches, the results often reflect geomodeler´s subjective assumptions. This thesis proposes an indicator probability modeling approach combined to dynamic anisotropy technique to define the geological domains of a structurally complex gold deposit. From the geological models, this work evaluates the appropriateness of uniform conditioning and localized uniform conditioning techniques on prediction of recoverable resource from exploratory sampling. The study compares the resource models from non-linear techniques to results obtained from ordinary kriging. The results were reconciliated to reference models created from the most detailed sampling set available. In addition, the methods were tested for the sensitivity level to the drilling pattern and the results compared to the reference models. The indicator probability models proved able to efficiently reproduce the ore outlines specially at the most detailed areas. The using of dynamic anisotropy allowed a better representation of the major folded geometries. The estimates by non-linear methods showed better results on reproducing the de distribution and recoverable resources of the reference models. Nevertheless, these techniques yielded worse results on representing locally the grades.

The assessment of the deep geothermal potential is an essential task during the early phases of any geothermal project. The well-known “Heat-In-Place” volumetric method is the most widely used technique to estimate the available stored heat and the recoverable heat fraction of deep geothermal reservoirs at the regional scale. Different commercial and open-source software packages have been used to date to estimate these parameters. However, these tools are either not freely available, can only consider the entire reservoir volume or a specific part as a single-voxel model, or are restricted to certain geographical areas. The 3DHIP-Calculator tool presented in this contribution is an open-source software designed for the assessment of the deep geothermal potential at the regional scale using the volumetric method based on a stochastic approach. The tool estimates the Heat-In-Place and recoverable thermal energy using 3D geological and 3D thermal voxel models as input data. The 3DHIP-Calculator includes an easy-to-use graphical user interface (GUI) for visualizing and exporting the results to files for further postprocessing, including GIS-based map generation. The use and functionalities of the 3DHIP-Calculator are demonstrated through a case study of the Reus-Valls sedimentary basin (NE, Spain).

EGU General Assembly 2021 EGU General Assembly 2021, vEGU21, online, 19 Apr 2021 - 30 Apr 2021; Wien : Copernicus 2 Seiten (2021). doi:10.5194/egusphere-egu21-4613, Published by Copernicus, Wien

C′ shear bands are ubiquitous structures in shear zones but their development is poorly understood. Previous research has determined they mostly occur in rocks with a high mechanical strength contrast. Using numerical models of viscoplastic deformation, we studied the effect of the proportion of weak phase and the phase strength contrast on C′ shear band development during simple shearing to a finite strain of 18. We found that C′ shear bands form in models with ≥5% weak phase when there is a moderate or high phase strength contrast, and they occur in all models with weak phase proportions ≥15%. Contrary to previous research, we find that C′ shear bands form when layers of weak phase parallel to the shear zone boundary rotate forwards. This occurs due to mechanical instabilities that are a result of heterogeneous distributions of stress and strain rate. C′ shear bands form on planes of low strain rate and stress, and not in sites of maximum strain rate as has previously been suggested. C′ shear bands are ephemeral and they either rotate backwards to the C plane once they are inactive or rotate into the field of shortening and thicken to form X- and triangle-shaped structures., M.A.F. acknowledges financial support of a Humboldt Research Fellowship for Postdoctoral Researchers provided by the Alexander von Humboldt Foundation. M-G. L. acknowledges the support of the Juan de la Cierva programme of the Government of Spain's Ministry for Science, Innovation, and Universities. E.G.R. acknowledges the Spanish Ministry of Science, Innovation and Universities for the “Ramón y Cajal” fellowship RYC2018-026335-I.

[eng] The objective of this thesis is to study the first-order dynamics of subduction systems characterized by opposite dip polarity in adjacent plate segments. The absence of previous studies analyzing the geodynamic evolution of these systems has defined the research strategy of the present work. Consequently, the thesis consists of three different parts combining analog experiments and numerical models of very simple double subduction systems and its application to the Westernmost Mediterranean where a subduction system with opposite polarity in adjacent plate segments (double polarity subduction) has been proposed to explain the formation and evolution of this region. Part 1. Analog experiments of subduction systems with opposite polarity in adjacent segments Firstly, I have studied the first-order plate dynamics of subduction systems with opposite polarity in adjacent plate segments by means of analog experiments. Laboratory experiments have been carried out in the Laboratory of Experimental Tectonics in Roma Tre University during a two month stay in Rome (Italy) under the advice of Prof. Dr. Francesca Funiciello and Prof. Dr. Claudio Faccenna. A total of eighteen experiments have been designed, including four with a single plate subduction as reference models. The laboratory experiments are composed of one or two separates plates made of silicon putty representing the lithosphere and glucose syrup representing the mantle. The plates are fixed at their back edge to enforce a slab rollback behavior and subduction is started by deflecting manually the leading edge of the plate (i.e., initial slab pull). Different setups have been designed to test the influence of the width of plates and the initial separation between them on the evolution of the system. Results show that the mantle flow induced by both plates is asymmetric relative to the axis of each plate causing a progressive merging of the toroidal cells that prevents a steady state phase of the subduction process and generates a net outward drag perpendicular to the plates. Trench retreat velocities depend on the relative position of the trenches, increasing when trenches approach to each other and decreasing when they separate after their intersection. Part 2. Reproducing analog experiments of subduction systems with numerical modeling Secondly, some of the previous laboratory experiments have been performed by means of numerical modeling to compare and complement previous results and quantify the relevant physical parameters characterizing a double polarity subduction system. Around thirty-five numerical models, in addition to preliminary tests, have been performed although only fifteen are presented in this thesis showing the most outstanding and satisfactory results. The set of the numerical models have been run in the supercomputer MARENOSTRUM 4 (Barcelona Supercomputing Center, Spain) and BRUTUS (Swiss Federal Institute of Technology, Switzerland), with an average computation time of 3 weeks per model. The 3D numerical setup is chosen with similar material parameters, geometry and dimensions as for previous subuction analog models consisting on one or two viscous plates descending into the upper mantle in opposite directions. Plates are fixed at their trailing edge to enforce roll-back behavior during density-driven subduction. A small perturbation is initially imposed to initiate subduction. Firstly, computational domain size, boundary conditions, rheology and thickness of plates are tested to find the numerical model that best represents analog experiments. Secondly, relevant parameters controlling the double polarity subduction process are studied by means of numerical techniques. Results show that the most suitable numerical boundary conditions to reasonably reproduce the analog results are free-slip at the lateral boundaries and no-slip at the bottom of the model. Lateral boundary conditions affect the evolution of the system at short distances allowing for a reduction of the size of the model domain relative to the analog model and to increase the resolution and saving computation time. Complementing previous experiments of double polarity subduction, numerical results show that the induced mantle flow generates a stress coupling between the adjacent plates slowing down the overall subduction process and producing lateral movement of plates and asymmetrical deformation of the slabs and trenches. Part 3. The Alboran and Algerian basins (Westernmost Mediterranean). A case study of double subduction with opposite polarity in adjacent segments. Finally, a 3D numerical model of double subduction with opposite polarity in adjacent plate segments has been performed simulating the tectonic setting of the Westernmost Mediterranean. The evolution of the Alboran-Tethys slab (Betic-Rif slab) is reproduced in this tectonic scenario studying the influence of the adjacent plate segment. Around forty numerical models have been performed varying physical and geometrical parameters, including preliminary numerical tests. In this thesis only the final double polarity subduction model and a single plate subduction model are presented. The numerical models have been run in the supercomputer MARENOSTRUM 4 (Barcelona Supercomputing Center, Spain) with an average computation time of 4 weeks per model. The model setup consists of two oceanic plate segments with a visco-plastic rheology subducting in opposite directions into the viscous upper mantle and starting at 35 Ma. In the present-day Alboran Basin region, the plate segment corresponding to the Alboran-Tethys slab (Betic-Rif slab) dips to the southeast with the trailing edge fixed to the Iberian margin. A continental African plate segment is included at the west side of this plate. In the present Algerian Basin region the plate segment (Tell-Kabylies slab) dips to the northwest and the trailing edge is fixed to the African margin. A small slab perturbation to account for the Africa- Iberia convergence prior to 35 Ma is initially imposed and the subsequent subduction process is driven by Rayleigh-Taylor instability. In addition, a reference model including only the Alboran-Tethys slab has been performed in order to study the influence of an adjacent plate segment subducting in opposite direction. Results show that the progressive curvature of the Alboran-Tethys slab is due to the lack of a transform zone in its connection with the Atlantic oceanic to the west and the strong segmentation of the African margin. This produces larger retreat velocities in the eastern side of the slab, where a transform zone separates the Alboran segment from the Algerian segment, than in the western side. Trench retreat velocities of both plate segments are measured concluding that the opening of the Alboran Basin occurs around 22 Ma. The influence of the adjacent Algerian segment generates an asymmetrical flow pattern around both trenches slowing down the overall subduction process of the Alboran plate segment., [spa] El objetivo de esta tesis consiste en estudiar la dinámica de sistemas de doble subducción con polaridad opuesta en segmentos adyacentes. La ausencia de estudios previos sobre el análisis de la evolución geodinámica de estos sistemas ha definido la estrategia de investigación del presente trabajo. En consecuencia, esta tesis consta de tres partes diferenciadas que combinan tanto experimentos análogos como modelos numéricos de sistemas de doble subducción y su posterior aplicación a la región del Mediterráneo occidental, donde se ha propuesto un sistema de doble subducción con polaridad opuesta en segmentos adyacentes para explicar su formación y evolución. Parte 1. Experimentos análogos de sistemas de subducción con polaridad opuesta en segmentos adyacentes La primera parte de esta tesis consiste en analizar la dinámica de los sistemas de doble subducción con polaridad opuesta en segmentos litosféricos adyacentes mediante experimentos análogos. Estos experimentos se han llevado a cabo en el Laboratorio de Tectónica Experimental en la Universidad de Roma Tre durante una estancia de dos meses en Roma (Italia) bajo la supervisión de la Prof. Dr. Francesca Funiciello y el Prof. Dr. Claudio Faccenna. Se han diseñado un total de dieciocho experimentos, incluyendo cuatro modelos de referencia de subducción simple (una placa). Estos experimentos consisten en una o dos placas elaboradas con silicona representando la litosfera y un tanque lleno de jarabe de glucosa representando el manto. Las placas se fijan en su borde posterior para imponer un comportamiento de retroceso de las fosas de subducción (trench rollback) y la subducción se inicia hundiendo manualmente el borde delantero de la placa. Se han diseñado diferentes configuraciones para probar la influencia en la evolución del sistema de la anchura de las placas y la separación inicial entre ellas. Los resultados muestran que el flujo del manto inducido por ambas placas es asimétrico con respecto al eje de cada placa. Esto provoca una fusión progresiva de las celdas toroidales impidiendo una fase de estabilización del proceso de subducción y generando una fuerza de arrastre neta que tiende a separar las placas. Las velocidades de retroceso de las fosas (velocidad de subducción) dependen de la posición relativa de éstas, aumentando cuando las fosas se acercan entre sí y disminuyendo cuando éstas se separan después de su alineación. Parte 2. Reproducción de experimentos análogos de sistemas de subducción mediante modelos numéricos En segundo lugar, se han realizado una serie de modelos numéricos, basados en los experimentos análogos realizados en la primera parte con el objetivo de comparar y complementar los resultados anteriores así como cuantificar los parámetros físicos más relevantes que caracterizan a un sistema de doble subducción con polaridad opuesta. En total, se han realizado alrededor de treinta y cinco modelos numéricos, además de las pruebas preliminares, aunque en esta tesis sólo se presentan quince de ellos mostrando los resultados más relevantes. Los modelos numéricos se han calculado principalmente en los supercomputadores MARENOSTRUM 4 (Centro de Supercomputación de Barcelona, España) y BRUTUS (Instituto Federal Suizo de Tecnología, Suiza), con un tiempo de cálculo promedio de 3 semanas por modelo. La configuración numérica 3D se elige con parámetros de geometría, dimensiones y materiales similares a los modelos análogos de subducción realizados anteriormente. Éstos consisten en una o dos placas viscosas que subducen en el manto superior en direcciones opuestas. Las placas están fijadas en su borde posterior imponiendo un comportamiento de retroceso de la fosa durante la subducción. La subducción se produce debido a la diferencia de densidades entre la placa y el manto a partir de una pequeña subducción impuesta inicialmente. En primer lugar, se estudian el tamaño del dominio computacional, las condiciones de contorno, la reología y el grosor de las placas para encontrar el modelo numérico que mejor representa el experimento análogo. En segundo lugar, se estudian los parámetros más relevantes que controlan el proceso de doble subducción con polaridad opuesta mediante técnicas numéricas. Los resultados muestran que las condiciones de contorno del modelo numérico más adecuadas para reproducir los experimentos análogos son el deslizamiento libre en las paredes laterales del dominio computacional y el deslizamiento nulo en la pared inferior. Las condiciones de contorno laterales sólo afectan a la evolución del sistema a distancias muy pequeñas, lo que permite una reducción del tamaño del dominio computacional en relación con el modelo análogo aumentando la resolución numérica y disminuyendo el tiempo de cálculo. De manera complementaria a los resultados observados en los experimentos análogos, los resultados numéricos muestran que el flujo inducido del manto genera un acoplamiento en la tensión entre las placas adyacentes, ralentizando el proceso de subducción. Así mismo, se produce un movimiento lateral entre las placas en superficie y una deformación asimétrica de las porciones subducidas (slabs) y de las fosas. Parte 3. Las cuencas de Alborán y Argelia (Mediterráneo occidental). Un caso de estudio de doble subducción con polaridad opuesta en segmentos adyacentes Finalmente, se ha realizado un modelo numérico 3D de doble subducción con polaridad opuesta en segmentos litosféricos adyacentes simulando la configuración tectónica del Mediterráneo occidental. El modelo numérico reproduce la evolución del segmento de placa de Alborán-Tethys estudiando la influencia del segmento de placa adyacente de Argelia- Tethys. Se han realizado alrededor de cuarenta modelos numéricos variando parámetros físicos y geométricos, incluyendo los modelos numéricos preliminares. En esta tesis sólo se presentan el modelo final de doble subducción con polaridad opuesta y de subducción simple. Los modelos numéricos se han calculado en el supercomputador MARENOSTRUM 4 (Centro de Supercomputación de Barcelona, España) con un tiempo de cálculo promedio de 4 semanas por modelo. El modelo consta de dos segmentos de placa oceánica con una reología viscoplástica que subducen en direcciones opuestas en el manto superior viscoso. El modelo se inicia hace 35 millones de años. En la región actual de la cuenca del Alborán, el segmento de placa de Alborán-Tethys subduce hacia el sureste con el borde posterior fijado al margen ibérico. Se incluye un segmento de placa continental africana en el lado oeste de esta placa. En la región actual de la cuenca argelina, el segmento de placa de Tell-Kabylies subduce hacia el noroeste y el borde posterior se fija al margen africano. El estado inicial del modelo considera la convergencia entre África e Iberia desde el temprano Cretácico hasta el tardío Eoceno imponiendo una subducción inicial de los segmentos de placa de 150 km. El posterior proceso de subducción es impulsado por la inestabilidad de Rayleigh-Taylor. Además, se ha realizado un modelo de referencia de placa simple que incluye sólo el segmento de Alborán-Tethys para estudiar la influencia del segmento adyacente subduciendo en dirección opuesta. Los resultados muestran que la curvatura progresiva de la placa de Alborán-Tethys se debe a la falta de una zona de transformación en su conexión con el océano Atlántico al oeste y la gran segmentación del margen africano. Esto produce unas velocidades de retroceso de la fosa mayores en el lado este de la placa de Alborán-Tethys que en el lado occidental, donde una zona de transformación la separa del segmento de Argelia-Tethys. El cálculo de las velocidades de retroceso de las fosas de ambos segmentos de placa concluyen que la apertura de la cuenca de Alborán se produjo aproximadamente hace 22 millones de años. La influencia del segmento argelino adyacente genera un patrón de flujo asimétrico alrededor de ambas fosas que ralentiza el proceso de subducción general del segmento de la placa de Alborán- Tethys.

Seismicity and distribution of earthquakes can provide active fault structural information on the crust at a regional scale. The morphology of faults can be derived from the epicentral distribution of micro-earthquakes. In this study, we combined both the relocated earthquake catalogue and related preliminary geophysical information for 3D modeling of the crust in the Xichang area, Sichuan province, China. The fault morphology and deep crustal structure were automatically extracted by the machine learning approach, such as the supervised classification and cluster analysis methods. This new 3D crustal model includes the seismic velocity distribution, fault planes in 3D and 3D seismicity. There are many earthquake clusters located in the folded basement and low-velocity zone. Our model revealed the topological relation between the folded basement and faults. Our work show the crustal model derived is supported by the earthquake clusters which in turn controls the morphological characteristics of the crystalline basement in this area. Our use of machine learning techniques can not only be used to predict the refined fault geometry, but also to combine the seismic velocity structure with the known geological information. This 3D crustal model can also be used for geodynamic analysis and simulation of strong motionseismic waves.

Three characteristic examples of the use of scientific engineering approaches for managing the technological processes of reservoir modeling at different hierarchical levels are presented in the article. The first example demonstrates the application of the spectral approach for modeling geophysical fields – the available log data is decomposed from the spectrum of Legendre polynomials, after which a stochastic field of the expansion coefficients is constructed. The results obtained by this method of realizing geophysical fields correspond to real data in a wider area of modeling than in classical methods. The speed of building models also increases due to the convenience of parallelization. The second example demonstrates the use of the source method to optimize the transfer of wells into injection. A flow rate of each well is found by simulating the wells in the development system as linear sources or sinks and recording the resulting system of equations for the flows at each time. According to the optimum of discounted extraction, there is an economically efficient time for well development. The third example demonstrates the application of the theory of dimensions to the problem of hydraulic fracturing modeling to determine the significance of certain parameters for the design of fracturing. By measuring the dependence of the fracture length on the injection volume, we obtain an empirical formula for the fracture length from its parameters, which determines the level of their significance.

In this paper, we propose a novel mesh repairing method for repairing voids from several meshes to ensure a desired topological correctness. The input to our method is several closed and manifold meshes without labels. The basic idea of the method is to search for and repair voids based on a multi-labeled mesh data structure and the idea of graph theory. We propose the judgment rules of voids between the input meshes and the method of void repairing based on the specified model priorities. It consists of three steps: (a) converting the input meshes into a multi-labeled mesh, (b) searching for quasi-voids using the breadth-first searching algorithm and determining true voids via the judgment rules of voids, (c) repairing voids by modifying mesh labels. The method can repair the voids accurately and only few invalid triangular facets are removed. In general, the method can repair meshes with one hundred thousand facets in approximately one second on very modest hardware. Moreover, it can be easily extended to process large-scale polygon models with millions of polygons. The experimental results of several data sets show the reliability and performance of the void repairing method based on the multi-labeled triangular mesh.

Deficiency of minerals, limited reserves of conventional hydrocarbon raw materials indicates the need to involve in the fuel and energy complex of other sources of hydrocarbons. Fields of super-viscous oil are one of the sources. This article is devoted to the study of sediments of the Permian sedimentary complex containing super-viscous oil deposits. The geological structure of the Lower Kazanian and Ufimian deposits is considered. A characteristic of the Sheshmian sandstone pack is given. The analysis of the set of geophysical studies is presented. Modeling of a shallow super-viscous oil deposit based on the lithologic-technological types of the productive formation was carried out, based on the results of drilling, core material and logging. The features of constructing the structural framework of a three-dimensional grid, and a lithological-technological model are highlighted. The distribution of porosity, permeability and oil saturation is described.

Sandy channelized reservoirs in deep water environments are of great importance for oil exploration and production as they can constitute important oil reservoirs. The twodimensional nature of the outcrops described in the literature and the local nature of the information acquired through wells are limiting factors for the adequate characterization of this type of sedimentary environment and its heterogeneities. The absence of information between the points sampled by wells in oil reservoir is usually overcome by using 3D seismic data. Geological modeling mitigates the effects of low seismic resolution and can be optimized regarding the spatial distribution of rock properties by incorporating inverted seismic volumes that have data throughout all the geological layers. This study presents a synthetic modeling of elastic properties associated with physical properties to assess and optimize the geostatistical modeling performed in real data from turbiditic reservoirs in the Maastrichtian section of the Calumbi Formation, Sergipe Sub-basin, Brazil. Geomorphological and geological aspects, described in the literature and in similar outcrops in the Alagoas Sub-basin, associated with their responses due to their compressional velocities, shear velocities, densities, and thicknesses, were successively tested to reduce the uncertainty in the spatial distribution between the points that present high vertical-resolution data. The results obtained show that the variations of the P and S waves are the main influences on the seismic signal and on the differences between impedance P and S attribute. An equation allowed to model the effects of these attributes and, thus, to implement corrections in the geometric and faciological characteristics of the evaluated rocks. Com a melhoria dos dados sísmicos 3D de alta resolução, juntamente com o intenso estudo de afloramentos análogos, o conhecimento sobre os depósitos de canais turbidíticos cresceu bastante nos últimos anos. Porém, mesmo com esses avanços tecnológicos e conceituais, a previsibilidade para esse tipo de reservatório continua sendo muito difícil, principalmente, em áreas com caráter exploratório. Os diferentes tipos de padrões de empilhamentos, além da variedade de preenchimento sedimentar desses depósitos, geram heterogeneidades internas difíceis de serem identificadas devido a limitação dos dados existentes na exploração de hidrocarbonetos. Uma forma de analisar o grau de conexão dos depósitos turbidíticos, principalmente em áreas com poucos poços perfurados e sem histórico de produção, é realizando um teste de formação. A modelagem geológica 3D e a simulação de fluxo são ferramentas que possibilitam uma análise de incerteza associadas ao comportamento de produção de diferentes cenários de ocorrência desses reservatórios, variando os parâmetros estáticos da geologia e os parâmetros dinâmicos da engenharia de reservatório. O trabalho teve como objetivo verificar o grau de comunicação hidráulica nos diferentes cenários de empilhamentos e preenchimentos de complexos de canais, a partir da simulação numérica de um teste de formação com vazão de produção constante de duzentas horas de fluxo. A mudança na deposição do complexo canalizado com predominância de migração lateral para um contexto de maior empilhamento vertical fez com que o grau de confinamento aumentasse. Os diferentes cenários de ocorrência de barreiras geraram pequenos confinamentos, mostrando que para ter muita influência na conectividade hidráulica, os depósitos canalizados precisam de barreiras de permeabilidade bastante efetivas. O aumento da permeabilidade intensificou o alcance da investigação do teste, encontrando barreiras mais rapidamente. O padrão de empilhamento e a variação de permeabilidade foram os fatores mais influentes nos resultados do teste de formação. São Cristóvão, SE

В настоящее время методы геостатистики применяются для исследования пространственного распределения геологических, технологических, геофизических и многих других признаков. В статье приведен пример использования геостатистической теории в отечественном программном обеспечении горногеологической информационной системе, программном комплексе МАЙНФРЭЙМ (MINEFRAME). Дано краткое описание этапов геостатистического анализа и приведены примеры их практического применения при изучении данных геологического опробования некоторых месторождений., Currently, geostatistical methods are used to study the spatial distribution of geological, technological, geophysical and many other properties. The article provides an example of the use of geostatistical theory in domestic software the mining and geological information system, the MINEFRAME software package. A brief description of the stages of geostatistical analysis is given and examples of their practical application in the study of geological testing of some deposits are given., №4 (2019)

This study presents a 3D geological model of reservoir rocks in the Mafia Basin based on interpretation of 2D seismic and well data towards understanding the hydrocarbon prospectivity. 2D seismic data were used to generate surface maps and therefore the subsurface configuration of the reservoir complemented with petrophysical analysis to determine lithology and reservoir properties. Structural and petrophysical properties modeling were distributed stochastically within the constructed 3D grid using Sequential Indicator Simulation (SIS) and Gaussian Random Function Simulation (GRFS) algorithms. Results from well log analysis and petrophysical models classify the reservoir under a moderate reservoir quality with 19% to 20% porosity, 6 - 7 mD permeability and 60% to 65% water saturation. The observed high values of water saturation imply that the hydrocarbon accumulation in the mapped area is insignificant. The reservoir structural model and subsurface configuration shows stratigraphical trap as the only trapping mechanism in the area.. However, 3D seismic and multiple wells are needed for effective correlation of geological information to enhance the structural configuration and lateral continuity of the reservoir.Keywords: Geological modeling; Mafia basin; 2D seismic data; reservoir rocks

En esta tesis se propone el uso de la Representación de Terrenos Basada en Stacks (SBRT, de sus siglas en inglés) para datos geológicos volumétricos. Esta estructura de datos codifica estructuras geológicas representadas como stacks utilizando una compacta representación de datos. A continuación, hemos formalizado la SBRT con un esquema basado en la teoría de geo-átomos para proporcionar una definición precisa y determinar sus propiedades. Esta tesis también introduce una nueva estructura de datos llamada QuadStack, mejorando los resultados de compresión proporcionados por la SBRT al aprovechar la redundancia de información que a menudo se encuentra en los datos distribuidos por capas. También se han proporcionado métodos de visualización para estas representaciones basados en el conocido algoritmo de visualización raycasting. Al mantener los datos en todo momento en la memoria de la GPU de forma compacta, los métodos propuestos son lo suficientemente rápidos como para proporcionar velocidades de visualización interactivas. In this thesis we propose the use of the Stack-Based Representation of Terrains (SBRT) for volumetric geological data. This data structure encodes geological structures represented as stacks using a compact data representation. The SBRT is further formalized with a framework based on the geo-atom theory to provide a precise definition and determine its properties. Also, we introduce QuadStacks, a novel data structure that improves the compression results provided by the SBRT, by exploiting in its data arrangement the redundancy often found in layered dataset. This thesis also provides direct visualization methods for the SBR and QuadStacks based on the well-known raycasting algorithm. By keeping the whole dataset in the GPU in a compact way, the methods are fast enough to provide real-time frame rates. Tesis Univ. Jaén. Departamento de Informática. Leída el 19 de septiembre de 2019.

Арктическая часть Западной Сибири содержит в себе основные объемы запасов и ресурсов углеводородов, доступных для освоения в ближайшее время в России. В настоящее время компанией «НОВАТЭК» здесь реализуются крупные проекты по производству сжиженного природного газа: «Ямал СПГ» и «Арктик СПГ 1, 2, 3». Объекты разработки имеют сложное геологическое строение, слабо изучены, расположены в неблагоприятных географоклиматических условиях и удалены от промышленно развитых регионов. Экономически эффективное освоение объектов такого типа является серьезным технологическим вызовом для нефтегазодобывающей отрасли, и обуславливает необходимость совершенствования технологий, существующих традиционных подходов и методик. В статье кратко освещены проблематика и основные достижения компании «НОВАТЭК» в геологоразведке и разработке. Материалы и методы Геологоразведочные работы, оценка и подготовка ресурсной базы, создание трехмерных геологических моделей, разработка и интегрированное моделирование месторождений., The Arctic part of Western Siberia contains main volumes of hydrocarbon reserves and resources available for development in Russia in the near future. Currently, the "NOVATEK" company is implementing major projects there to produce liquefied natural gas: "Yamal LNG" and "Arctic LNG 1, 2, 3". The development targets have complex geological structure, are poorly studied and located in harsh climatic and geographical conditions, far from industrialized regions. Cost-effective development of such objects is currently a major technological challenge for oil and gas industry, which necessitates the improvement of existing conventional technologies, approaches and techniques. The article summarizes the problems and main achievements of the company "NOVATEK" in exploration and development. Materials and methods Hydrocarbon exploration, evaluation and maturation of prospects, geological modeling, field development, integrated dynamic modeling of deposits.

Optimal upscaling of a high-resolution static geologic model that reflects the flow performance of the reservoir is important for reasons such as time and calculation efficiency. In this study, we demonstrate that honoring reservoir heterogeneity is critical in predicting accurate production and reducing the time and cost of running reservoir flow simulations for the Hunton Group carbonate. We integrated three-dimensional (3D) seismic data, well logs, thin sections, multiscale fracture studies, discrete fracture networks, and geostatistical methods to create a 100 &times, 150 &times, 1 ft gridded representative geologic model. We calibrated our gridded porosity and permeability parameters, including the evaluation of fractures, by history matching the simulated production rate and cumulative production volumes from a baseline fine-scale model generated from petrophysical and production data obtained from five wells. We subsequently reperformed the simulations using a suite of coarser grids to validate our property upscaling workflow. Compared to our baseline history matching, increasing the horizontal grid cell sizes (i.e., horizontal upscaling) by factors of 2, 4, 8, and 16 results in cumulative production errors ranging from +0.5% for two time (2&times, ) coarser to +74.22% for 16&times, coarser. The errors associated with vertical upscaling were significantly less, i.e., ranging from +0.5% for 2&times, coarser to +10.8% for 16&times, coarser. We observed higher production history matching errors associated with natural fracture size. Results indicate that greater connectivity provided by natural fracture length has a larger effect on production compared to the higher permeability provided by larger apertures. We also estimated the trade-off between accuracy and run times using two methods: (a) using progressively larger grid cell sizes, (b) applying 1, 5, 10, and 20 parallel processes. Computation time reduction in both scenarios may be described by simple power law equations. Observations made from our case study and upscaling workflow may be applicable to other carbonate reservoirs.

Part 4: MAKE-Topology; International audience; We discuss the possibility of applying stochastic approaches to core modeling by using tools of topology. The study demonstrates the prospects of applying topological characteristics for the description of the core and the search for its analogs. Moreover application of topological characteristics (for example, in conjunction with machine learning methods) in the long term will make it possible to obtain petrophysical properties of the core samples without carrying out expensive and long-term filtration experiments.

GeoResJ 6, 202-212 (2015). doi:10.1016/j.grj.2015.04.001 special issue: "Rescuing Legacy Data for Future Science / Edited by Kerstin Lehnert, Leslie Hsu, Mark A. Parsons and Lesley Wyborn", Published by Elsevier, Amsterdam [u.a.]

Orientador: Sueli Yoshinaga Pereira Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociências Resumo: Um sistema de transmissão HVDC é composto por duas Subestações Conversoras, interligadas pela linha HVDC, cada uma com um eletrodo de aterramento separado do seu pátio CC, geralmente localizado de 15 km a 150 km de distância e conectado por meio da linha do eletrodo. Os eletrodos HVDC proporcionam redução de custos e agregam confiabilidade ao sistema de transmissão de energia. Os eletrodos geralmente dissipam na terra a corrente de desequilíbrio do bipolo, entre 20 A a 40 A. No caso de perda de um polo da linha HVDC, a energia pode ser transmitida pelo polo remanescente com retorno pela terra, utilizando os eletrodos de aterramento para a injeção de correntes que chegar a quase 4 kA, o que pode resultar em interferências em uma área ampla, dependendo da estrutura geológica. A seleção dos locais de construção dos eletrodos deve ser realizada dentro de um raio de algumas dezenas de quilômetros ao redor das subestações, nas duas extremidades da linha HVDC. O melhor local em cada extremidade é aquele que apresenta a estrutura geoelétrica com resistividades mais baixas, desde a superfície do solo até pelo menos o meio da crosta. Esta tese apresenta o desenvolvimento do modelo geoelétrico 1D para o eletrodo sul do sistema HVDC do Rio Madeira, bipolo 1, localizado em Araraquara, na Bacia Sedimentar do Paraná, sul do Brasil. O eletrodo é constituído por um anel aproximadamente retangular de poços (cerca de 820 m x 560 m), cada um revestido por tubos de aço com profundidades variáveis, entre 20 m e 40 m de profundidade. O modelo geoelétrico deve ser representativo da média do solo raso, até a profundidade dos poços, combinada com um modelo profundo. A modelagem do solo raso foi desenvolvida a partir de uma campanha de sondagens Schlumberger e da perfilagem por indução de poços de monitoramento perfurados no local. O modelo profundo foi construído a partir de uma campanha magnetotelúrica (MT). Os modelos geoelétricos são aprimorados ao longo do projeto, à medida que mais dados geofísicos e geotécnicos são levantados. O modelo de projeto tem um ajuste final após o comissionamento do eletrodo, pois o desempenho elétrico medido permite um ajuste complementar do desvio estático da curva de resistividades aparentes MT. Uma medição independente do potencial tubo-solo foi feita no gasoduto Bolívia-Brasil, a 26 km do eletrodo, sendo o valor medido comparado com o potencial calculado a partir da simulação do eletrodo com o modelo geoelétrico final, com ambos os valores apresentando boa compatibilidade Abstract: A HVDC transmission system comprises two Converter Substations, interconnected by the HVDC line, each one requiring a separate grounding electrode for its DC switchyard, which usually is located from 15 km to 150 km away and connected by means of the electrode line. HVDC electrodes allow for cost reduction and add reliability to the energy transmission system. The electrodes usually dissipate into the ground the unbalance current of the bipole, about 20 A to 40 A. In case of the loss of one pole of the HVDC line, the energy can be transmitted by the remaining pole with ground return, using grounding electrodes for the injection into the ground currents that may reach almost 4 kA, which may produce interferences within a wide area, depending on the tectonic setting. The electrodes Site Selection shall be carried up within a radius of some tens of kilometers around the substations at the two ends of the HVDC line. The best site at each end is the one with the geoelectric structure that presents lower resistivities, from soil surface down to at least mid-crust. This thesis presents the development of the 1D geoelectric model for the South electrode of Rio Madeira HVDC system, bipole 1, located at Araraquara, in the Paraná Sedimentary Basin, South of Brazil. The electrode is constituted by an approximately rectangular ring of wells (about 820 m x 560 m), each one lined with steel pipes with varying depths, between 20 m to 40 m deep. The geoelectric model shall represent the average of the shallow ground, down to the depth of the wells, combined with a deep model, down to the mid-crust. The modeling of the shallow ground was developed from a Schlumberger survey and from the induction profiling of monitoring wells drilled in the site. The deep model was built from a magnetotelluric (MT) survey. The models are improved along the project, as more geophysical and geotechnical data are surveyed. The design model has a final adjustment after the electrode commissioning, because the measured electrical performance allows for a complementary adjustment of the MT static deviation. An independent measurement of pipe-to-ground potential was done at the Bolivia-Brazil pipeline, 26 km away from the electrode, which was compared with the potential calculated from the electrode simulation using the final geoelectric model, with both values presenting good compatibility Doutorado Geologia e Recursos Naturais Doutor em Geociências

Виконано огляд та аналіз основних об'єктів моделювання в нафтогазовій промисловості – родовищ, процесу буріння свердловин, технологічних процесів та пристроїв нафтових і газових промислів, транспорту флюїдів та пульп. Визначено характерні особливості об'єктів моделювання, способи моделювання, програмне забезпечення, наведені приклади моделювання окремих об'єктів. Визначені перспективні напрямки розвитку математичного моделювання об'єктів в нафтогазовій промисловості. Системно проаналізовано основні об'єкти моделювання в нафтогазовій промисловості та методи і програмні продукти використовувані для моделювання. The review and analysis of the main modeling objects in the oil and gas industry – deposits, the process of drilling wells, technological processes and devices of oil and gas fields, transport of fluids and pulps. Specific features of modeling objects, modeling methods, software, specific modeling examples of individual objects are given. Prospective directions of development of mathematical modeling of key objects in the oil and gas industry are determined. Systematically analyzed the main modeling objects in the oil and gas industry, modern methods and software products used for modeling.

The planning stages of mining activities require many comprehensive and detailed analyses. Determining the correct orebody model is the first stage and one of the most important. Three-dimensional solid modeling is one of the significant methods that can examine the position and shape of the ore deposit. Although there are many different types of mining software for determining a solid model, many users try to build geological models in the computer without knowing how these software packages work. As researchers on the subject, we wanted to answer the question "How would we do it". For this purpose, a system was developed for generating solid models using data obtained from boreholes. Obtaining this model in an AutoCAD environment will be important for geologists and engineers. Developed programs were first tested with virtual borehole data belonging to a virtual deposit. Then the real borehole data of a cement raw material site were successfully applied. This article allows readers not only to see a clear example of the programming approach to layered deposits but also to produce more complicated software in this context. Our study serves as a window to understanding the geological modeling process.

Геологическое и гидродинамическое моделирование активно применяется большинством недропользователей при разработке месторождений для наиболее полного извлечения запасов при минимальных экономических затратах. В статье показан вариант ремасштабирования геологической модели на примере залежи триасовых отложений одного из месторождений Красноленинского свода для сокращения затрат машинного времени расчетов и сохранения возможности фильтрации при высокой плотности сетки скважин. Использован послойный геолого-статистический разрез (ГСР) как эффективный метод оценки достоверности ремасштабирования., Geological and hydrodynamic modeling is actively used by most subsoil users in the development of deposits for the most complete extraction of deposits with minimal economic costs. The article discusses the option of rescaling the geological model using the example of Triassic deposits of one of the Krasnoleninsky arch fields to reduce the machine time of calculations and preserve the possibility of filtration at a high density of the head well grid. A layered geological-statistical section (GSS) was used as an effective method for estimating the reliability of rescaling.