Master of Science / Department of Geology / Abdelmoneam Raef / Matthew W. Totten / This work focuses on the use of advanced seismically driven technologies to estimate the distribution of key reservoir properties which mainly includes porosity and hydrocarbon reservoir pay. These reservoir properties were estimated by using a multitude of seismic attributes derived from post-stack high resolution inversions, spectral imaging and volumetric curvature. A pay model of the reservoir in the Wierman field in Ness County, Kansas is proposed. The proposed geological model is validated based on comparison with findings of one blind well. The model will be useful in determining future drilling prospects, which should improve the drilling success over previous efforts, which resulted in only few of the 14 wells in the area being productive. The rock properties that were modeled were porosity and Gamma ray. Water saturation and permeability were considered, but the data needed were not available. Sequential geological modeling approach uses multiple seismic attributes as a building block to estimate in a sequential manner dependent petrophysical properties such as gamma ray, and porosity. The sequential modelling first determines the reservoir property that has the ability to be the primary property controlling most of the other subsequent reservoir properties. In this study, the gamma ray was chosen as the primary reservoir property. Hence, the first geologic model built using neural networks was a volume of gamma ray constrained by all the available seismic attributes. The geological modeling included post-stack seismic data and the five wells with available well logs. The post-stack seismic data was enhanced by spectral whitening to gain as much resolution as possible. Volumetric curvature was then calculated to determine where major faults were located. Several inversions for acoustic impedance were then applied to the post-stack seismic data to gain as much information as possible about the acoustic impedance. Spectral attributes were also extracted from the post-stack seismic data. After the most appropriate gamma ray and porosity models were chosen, pay zone maps were constructed, which were based on the overlap of a certain range of gamma ray values with a certain range of porosity values. These pay zone maps coupled with the porosity and gamma ray models explain the performance of previously drilled wells.

Orientadores: Alessandro Batezelli, Emilson Pereira Leite / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-27T08:51:15Z (GMT). No. of bitstreams: 1 Correia_UlissesMigueldaCosta_M.pdf: 6847443 bytes, checksum: 0df13d40b34baadeb0dad7f1a2a1e2ea (MD5) Previous issue date: 2015 / Resumo: A modelagem estática de reservatórios tem um papel fundamental na fase de avaliação do potencial de um campo. A modelagem integrada permite um melhor entendimento da relação entre a geologia local e os sistemas deposicionais através da distribuição das fácies e das variáveis petrofísicas. A integração de dados geológicos e geofísicos por meio da geostatística é crucial para uma modelagem e caracterização de reservatórios mais robusta. Nesse trabalho foi construído um cenário de modelo geológico estático do reservatório da Formação Carapebus da Bacia de Campos. A metodologia aplicada foi compreendida em cinco fases: (1) idealização de um modelo conceitual, (2) construção de um modelo estrutural, (3) geração de 100 realizações de simulação sequencial da indicatriz para obter modelos de litofácies, (4) geração de 100 realizações de simulação sequencial gaussiana para obter modelos petrofísicos de porosidade e permeabilidade, e (5) validação dos modelos visando à coerência estatística e geológica. Para a construção dos modelos de litofácies e de net-to-gross foi aplicado o algoritmo geostatístico de simulação sequencial da indicatriz e para os modelos petrofísicos foi aplicado o algoritmo de simulação sequencial Gaussiana com recurso à co-krigagem co-localizada, no caso da permeabilidade. A metodologia foi aplicada a um estudo de caso real. Foi necessário o estabelecimento de um conjunto de premissas. Os resultados mostraram que os modelos obtidos honram os dados condicionantes e provam ser consistentes. Estes modelos permitiram caracterizar o reservatório como moderadamente homogêneo com V=0.52, no intervalo da maioria dos reservatórios silicilclásticos como demostrado pelo coeficiente de variabilidade de permeabilidade de Dykstra-Parsons. Contudo há limitações com relação à, (1) densidade amostral dos dados, e (2) conhecimento e experiência do tipo de reservatório em estudo e respetivas heterogeneidades. Pelo fato de os modelos serem representações digitais de uma realidade de elevada complexidade, a consistência geológica precisa ser testada e validada através de um processo iterativo de geração e ajuste de modelos / Abstract: Reservoir static modelling plays a fundamental role in the evaluation phase of a petroleum field. Integrated modelling allows a better understanding on how the local geology and depositional systems relate to each other, by facies and petrophysical parameters distribution. Geostatistics integrates geological and geophysical data, playing a key role in reservoir modelling and characterisation. In this study a scenario of geological static model of the Carapebus Formation of Campos Basin were built. The methodology applied was divided in five phases: (1) thinking of a conceptual model, (2) building of a structural model, (3) building of 100 realizations of sequential indicator simulation for cell-based lithofacies modelling, (4) building of 100 realizations of sequential Gaussian simulation for porosity and permeability modelling, and (5) models validation by targeting both statistical and geological consistency. To build the lithofacies and net-to-gross models, the sequential indicator simulation algorithm was applied; for the petrophysical models, the selected algorithms were sequential Gaussian simulation, with co-located co-kriging for permeability models. Seismic attributes were valuable in the interpretation of structures and sedimentary features. This methodology was applied to a real case study from Campos Basin, the siliciclastic reservoir of Carapebus Formation in Campos Basin. Some premises were established for the methodology implementation. The obtained models honoured the conditioning data and shown consistency. Also, the models allowed to characterize this reservoir as moderately homogenous with V=0.52, within the range of most siliciclastic reservoirs demonstrated by Dykstra-Parsons coefficient of permeability variation. However there are some limitations closely related to the, (1) dataset density, and (2) a previous knowledge and experience by the user with this type of reservoir. Considering that the models are digital representations of a highly complex reality, the geological consistency needs to be tested and validated through an iterative process of creating and fitting the models / Mestrado / Geologia e Recursos Naturais / Mestre em Geociências

La démarche d’intégration des hétérogénéités dans les modèles réservoirs en est à ses prémices dans le domaine du stockage géologique de CO2. C’est dans ce contexte que s’inscrivent ces travaux de thèse. Un protocole d’analyse depuis l’étude de terrain jusqu’aux simulations réservoirs a été établi. La caractérisation du Minjur Sandstone (formation Triasique d’Arabie Centrale) met en avant le caractère crucial de la connectivité des corps dans l’architecture du réservoir, notamment en liant génétiquement leur nature, leur connectivité et leur position dans la séquence de dépôt. S’appuyant sur la connaissance de cette formation, un modèle conceptuel est construit, puis reproduit stochastiquement par un algorithme permettant l’élaboration de modèles conditionnés par une histoire sédimentaire. Le protocole prévoit la création de 50 scénarios illustrant divers degrés de connectivité ; chaque scénario étant composé de deux modèles de même architecture mais à remplissage sédimentaire différent. Cette approche permet d’appréhender (a) l’impact de la connectivité et (b) des hétérogénéités sédimentaires sur les performances réservoirs. L’estimation de capacité par l’approche statique des volumes disponibles estime une capacité moyenne d’environ 13Mt (aquifère semi-infini de 25 km par 25 km et 60m d’épaisseur à 1000 m de profondeur). Les hétérogénéités internes (sédiments argileux appelés oxbow lakes) entraînent une différence de capacité de 30%. Les simulations dynamiques confirment ces résultats et révèle une variabilité de capacité de 23% liée la connectivité des corps. De plus les hétérogénéités réduisent la migration verticale du gaz ce qui peut augmenter l’intégrité du stockage. / In the CO2 storage context, heterogeneity has only been rarely considered in reservoir models to date. To address this key issue, the project aims at developing a workflow that manages the heterogeneity from the field observations up to the reservoir simulation. The characterisation of the Minjur Sandstone (a Triassic formation from Central Saudi Arabia) shows the crucial role of connectivity in the reservoir architecture, and the genetic link between the nature, location and connectivity of the sedimentary bodies in the sequence. Stemming from this study, a conceptual model was established and stochastically reproduced through an algorithm simulating models conditioned to a sedimentary history. Fifty scenarios were simulated, representing various connectivity degrees. Each of these scenarios is composed of two models, identical by their architecture but different in their internal sedimentary fill. This approach allows the study of the impact of the (a) reservoir bodies’ connectivity and (b) their internal sedimentary heterogeneity on the reservoir’s performances. The capacity estimates using a static calculation based on the available pore volumes reveals a mean capacity of 13 Mt (for a 25 x 25 km x 60 m semi finite aquifer at 1000m deep). The sedimentary heterogeneity (shaly deposits called oxbow lakes) is responsible for a 30% difference of capacity. The flow simulations confirm these results and show that the connectivity of the reservoir bodies creates a 23% capacity variation. Moreover, the heterogeneities tend to reduce the amount of CO2 able to reach the uppermost reservoir which may enhance the storage integrity.

Accessibility to consistent subsurface hydrostratigraphic information is crucial for the development of robust groundwater flow and contaminant transport models. However, full three-dimensional understanding of the subsurface geology is often the missing link. Construction of watershed-scale hydrostratigraphic models continues to be limited by the quality and density of borehole data which often lack detailed geologic information. This can become a serious problem where rapid sediment facies changes and intricate sediment architecture occur. This research is motivated by the idea that if we can understand more about the distribution of sediments and structures of complex deposits, we learn more about depositional processes and how they affect the internal geometry of a deposit and the distribution of hydraulic properties. One approach is to study surficial excavations (e.g. sand and gravel pits) that often punctuate shallow aquifers. The purpose of this study is to develop and test a method of integrating high-resolution georeferenced stratigraphic and sedimentologic information from sand and gravel pits as a means to better document sedimentologic data and improve understanding of the depositional environments. The study area is located within the Waterloo Moraine, in southwestern Ontario, and is an unconsolidated shallow aquifer system with a complex internal architecture and sediment heterogeneity. The method involves the integration of high-resolution field data with borehole and geophysical information in a computer-based 3D environment. A total of fourteen virtual sedimentary sections were constructed by georegistering digital photographs within a framework of georeferenced positions collected using a reflectorless total station and GPS. Fourteen sediment facies have been described in the field. These include crudely stratified gravel beds, planar and cross-laminated sandy strata (ripple and dune scales), along with laminated and massive silty and clayey beds. Calculated hydraulic conductivities span over seven orders of magnitude. The analysis of a single excavation has shown contrasting sediment assemblages from one end of the pit to the other, highlighting the complexity of the Waterloo Moraine. The heterogeneous and deformed layers of gravel, sand, and mud may be the product of an ice-contact to ice-proximal environment, whereas the extensive sandy assemblages may reflect an intermediate subaqueous fan region. The results also suggest that the borehole database overestimates the amount of fine-grained material in the study area. Finally, this research demonstrates that it is possible to build in a timely manner a 3D virtual sedimentologic database. New emerging technologies will lead to increased resolution and accuracy, and will help streamline the process even further. The possibility of expanding the 3D geodatabase to other excavations across the region in a timely manner is likely to lead to improved hydrostratigraphic models and, by extension, to more efficient strategies in water resources planning, management and protection.

Accessibility to consistent subsurface hydrostratigraphic information is crucial for the development of robust groundwater flow and contaminant transport models. However, full three-dimensional understanding of the subsurface geology is often the missing link. Construction of watershed-scale hydrostratigraphic models continues to be limited by the quality and density of borehole data which often lack detailed geologic information. This can become a serious problem where rapid sediment facies changes and intricate sediment architecture occur. This research is motivated by the idea that if we can understand more about the distribution of sediments and structures of complex deposits, we learn more about depositional processes and how they affect the internal geometry of a deposit and the distribution of hydraulic properties. One approach is to study surficial excavations (e.g. sand and gravel pits) that often punctuate shallow aquifers. The purpose of this study is to develop and test a method of integrating high-resolution georeferenced stratigraphic and sedimentologic information from sand and gravel pits as a means to better document sedimentologic data and improve understanding of the depositional environments. The study area is located within the Waterloo Moraine, in southwestern Ontario, and is an unconsolidated shallow aquifer system with a complex internal architecture and sediment heterogeneity. The method involves the integration of high-resolution field data with borehole and geophysical information in a computer-based 3D environment. A total of fourteen virtual sedimentary sections were constructed by georegistering digital photographs within a framework of georeferenced positions collected using a reflectorless total station and GPS. Fourteen sediment facies have been described in the field. These include crudely stratified gravel beds, planar and cross-laminated sandy strata (ripple and dune scales), along with laminated and massive silty and clayey beds. Calculated hydraulic conductivities span over seven orders of magnitude. The analysis of a single excavation has shown contrasting sediment assemblages from one end of the pit to the other, highlighting the complexity of the Waterloo Moraine. The heterogeneous and deformed layers of gravel, sand, and mud may be the product of an ice-contact to ice-proximal environment, whereas the extensive sandy assemblages may reflect an intermediate subaqueous fan region. The results also suggest that the borehole database overestimates the amount of fine-grained material in the study area. Finally, this research demonstrates that it is possible to build in a timely manner a 3D virtual sedimentologic database. New emerging technologies will lead to increased resolution and accuracy, and will help streamline the process even further. The possibility of expanding the 3D geodatabase to other excavations across the region in a timely manner is likely to lead to improved hydrostratigraphic models and, by extension, to more efficient strategies in water resources planning, management and protection.

No description available.

In Geostatistical modelling of the spatial distribution of rock attributes, the multivariate distribution of a Random Function defines the range of possible values and the spatial relationships among them. Under a decision of stationarity, the Random Function distribution and its statistics are inferred from data within a spatial domain deemed statistically homogenous. Assuming stationary multiGaussianity allows spatial prediction techniques to take advantage of this simple parametric distribution model. These techniques compute the local distributions with surrounding data and global spatially invariant statistics. They often fail to reproduce local changes in the mean, variability and, particularly, the spatial continuity, that are required for geologically realistic modelling of rock attributes. The proposed alternative is to build local Random Function models that are deemed stationary only in relation to the locations where they are defined. The corresponding location-dependent distributions and statistics are inferred by weighting the samples inversely proportional to their distance to anchor locations. These distributions are locally Gaussian transformed. The transformation models carry information on the local histogram. The distance weighted experimental measures of spatial correlation are able to adapt to local changes in the spatial continuity and are semi-automatically fitted by locally defined variogram models. The fields of local variogram and transformation parameters are used in locally stationary spatial prediction algorithms. The resulting attribute models are rich in non-stationary spatial features. This process implies a higher computational demand than the traditional techniques, but, if data is abundant enough to allow a reliable inference of the local statistics, the proposed locally stationary techniques outperform their stationary counterparts in terms of accuracy and precision. These improved models have the potential of providing better decision support for engineering design. / Mining Engineering

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No. of bitstreams: 12 Dissertação - Paulo Elias Carneiro Pereira (1).pdf: 17644242 bytes, checksum: ab5fa50d404a6c4a211b84194b2443f2 (MD5) Dissertação - Paulo Elias Carneiro Pereira (2).pdf: 16660004 bytes, checksum: cf5e68fe373f5599a5185def4cd2dbc9 (MD5) Dissertação - Paulo Elias Carneiro Pereira (3).pdf: 16826382 bytes, checksum: d132111aea6718262b141b27469610cf (MD5) Dissertação - Paulo Elias Carneiro Pereira (4).pdf: 18524080 bytes, checksum: f823b94af26d66b0c3372283946a4faf (MD5) Dissertação - Paulo Elias Carneiro Pereira - 2017 (5).pdf: 18542428 bytes, checksum: fcbc6bc33ae4ce8f406d45226db9cec1 (MD5) Dissertação - Paulo Elias Carneiro Pereira - 2017 (6).pdf: 16491972 bytes, checksum: 700456f830447b127f5ebba098ae0777 (MD5) Dissertação - Paulo Elias Carneiro Pereira - 2017 (7).pdf: 17053967 bytes, checksum: 282d9a25fc2337ddbbe0d09a801e9821 (MD5) Dissertação - Paulo Elias Carneiro Pereira - 2017 (8).pdf: 13201210 bytes, checksum: c784be01d079249a502dd2dff455ca27 (MD5) Dissertação - Paulo Elias Carneiro Pereira - 2017 (9).pdf: 16669209 bytes, checksum: caf85a078ee9178fcd2989dca14ad6c6 (MD5) Dissertação - Paulo Elias Carneiro Pereira - 2017 (10).pdf: 16406537 bytes, checksum: 9019ab1ca27b30efd351da8c77f3ac36 (MD5) Dissertação - Paulo Elias Carneiro Pereira - 2017 (11).pdf: 3595306 bytes, checksum: 2cc84e96aca8430238c275c770941926 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-03-08 / A mining enterprise is composed of a set of successive and interdependent phases between them, which may or may not culminate in the exploitation of the mineral assets. The project begins with a Mineral Exploration phase, whose objective is to discover and subsequently evaluate the deposit for the feasibility of its extraction. This process involves setting the shape, dimensions and grades, resulting in a model that will be used to determine the recoverable reserves, that is, the economically usable part of the mineral resource, which will base the decision on the implementation or not of the enterprise, based mainly on technicaleconomic criteria. The elaboration of the physical form of the geological bodies that control the mineralization (geological model) and the estimation of the geological variables that characterize the quality of the different materials can be done by two approaches: by traditional or by geostatistical methods. The latter approach is currently being preferred, as it is a more accurate alternative and therefore, more reliable over traditional methods. The work uses indicator kriging (IK) and ordinary kriging (OK), both geostatistical tools, for the determination of the geological model and estimation of the geological variables (grades), respectively, of a limestone deposit located at Indiara city, Goiás State. Finally, from the obtained model the optimal limits of the extraction were established, based on the algorithm of Lerchs-Grossmann, that maximize the net present value of the enterprise. The results showed a significant deviation between themodel calculated by IK and the reality (samples), which can have as consequence the present spatial configuration of the sample data. The estimated geological variables also showed important deviations (overestimation and/or underestimation), particularly MgO oxide. The areas of occurrence of such deviations were coincident for all variables, which makes evident the existence of problems with the current sampling grid (spacing between samples and presence of very different sample supports), in such a way that it is recommended to collect additional samples, particularly with standardized supports. The optimal pit delimited a total reserve of 109,436,160.43 tons, with a total strip ratio of 0.13, which makes the venture, at first, attractive. This configuration, however, tends to be modified according to the collection of new geological evidence. / Um empreendimento mineiro é composto por um conjunto de fases sucessivas e interdependentes entre si, as quais podem culminar ou não na explotação do bem mineral. O projeto se inicia com uma fase de Exploração Mineral, cujo objetivo é descobrir e subsequentemente avaliar o depósito quanto à viabilidade de sua extração. Tal processo envolve estabelecer a forma, as dimensões e os teores, resultando em um modelo que será utilizado para a determinação das reservas lavráveis, ou seja, a parte economicamente aproveitável do recurso mineral, a qual fundamentará a decisão sobre a implantação ou não do empreendimento a partir de critérios principalmente técnico-econômicos. A elaboração do formato físico dos corpos geológicos que controlam a mineralização (modelo geológico) e a estimativa das variáveis geológicas que caracterizam a qualidade dos diferentes materiais podem ser feitas a partir de duas abordagens: por métodos tradicionais ou por geoestatísticos. Os últimos têm sido utilizados recentemente como uma proposta mais precisa em relação aosmétodos tradicionais. O trabalho utiliza a krigagem indicadora (KI) e a krigagem ordinária (KO), ambas ferramentas geoestatísticas, para a determinação do modelo geológico e estimativa das variáveis geológicas (teores), respectivamente, em um depósito de calcário situado no município de Indiara, estado de Goiás. Por fim, a partir do modelo obtido estabeleceu-se os limites ótimos da extração baseados no algoritmo de Lerchs-Grossmann, que maximizamo valor presente líquido do empreendimento. Os resultados mostraram um desvio significativo entre o modelo calculado pela KI e realidade (amostras), o que pode ter como consequência significativa a atual configuração espacial da amostragem. As variáveis geológicas estimadas também demonstraram desvios (sobrestimativa e subestimativa) importantes, particularmente o óxido MgO. As áreas de ocorrência de tais desvios foram coincidentes para todas as variáveis, o que torna evidente a existência de problemas com a atual malha de amostragem (espaçamento entre amostras e presença suportes amostrais muito diferentes), de tal forma que se recomenda a coleta de amostras adicionais, e de suportes padronizados. A cava ótima delimitou uma reserva total de 109.436.160,43 toneladas, com uma relação estéril-minério (REM) total de 0,13, o que torna o empreendimento, a princípio, atrativo. Tal configuração, entretanto, tende a ser alterada conforme a coleta de novas evidências geológicas.

Cette thèse doctorale aborde divers aspects méthodologiques de l’analyse de levés électromagnétiques aéroportés en domaine temporel (TDEM) pour une interprétation détaillée à finalités géologique et hydrogéologique. Ce travail s’est appuyé sur un levé réalisé dans la région de Courtenay (Nord-Est de la région Centre) caractérisée par un plateau de craie karstifié (karst des Trois Fontaines) recouvert par des argiles d’altération et des alluvions. Tout d’abord, une méthode de filtrage des données TDEM utilisant la Décomposition en Valeurs Singulières (SVD) a été développée. L’adaptation rigoureuse de cette technique aux mesures TDEM a permis de séparer avec succès les bruits, qui ont pu être cartographiés, et le « signal géologique », diminuant grandement le temps nécessaire à leur traitement. De plus, la méthode s’est avérée efficace pour obtenir, rapidement, des informations géologiques préliminaires sur la zone. Ensuite, une analyse croisée entre le modèle de résistivité obtenu en inversant les données filtrées et les forages disponibles a été effectuée. Celle-ci a mené à une amélioration de la connaissance géologique et hydrogéologique de la zone. Une figure d’ondulation, séparant deux dépôts de craie, et le réseau de failles en subsurface ont pu être imagés, apportant un cadre géologique au karst des Trois Fontaines. Enfin, une nouvelle méthode combinant l’information aux forages et les pentes issues du modèle de résistivité EM a permis d’obtenir un modèle d‟une précision inégalée du toit de la craie. L’ensemble de ces travaux fournit un cadre solide pour de futures études géo-environnementales utilisant des données TDEM aéroportées, et ce, même en zone anthropisée. / This PhD thesis addresses various methodological aspects of the analysis of airborne Time Domain ElectroMagnetic (TDEM) surveys for a detailed interpretation in geological and hydrogeological purposes. This work was based on a survey conducted in the region of Courtenay (north-east of the Région Centre, France) characterized by a plateau of karstified chalk (karst des Trois Fontaines) covered by weathering clays and alluvium. First, a TDEM data filtering method using the Singular Value Decomposition (SVD) was developed. The rigorous adaptation of this technique to TDEM data has successfully separated the noise, which was mapped, and the “geological signal”, greatly reducing the time required for processing. Furthermore, the method has proved to be effective to obtain quick preliminary geological information on the area. Then, a cross analysis between the resistivity model obtained by inverting the filtered data and the available boreholes was conducted. This has led to the improvement of the geological and hydrogeological knowledge of the area. An undulating feature, separating two chalk deposits, and a fault network were imaged in subsurface, providing a geological framework for the Trois Fontaines karst. Finally, a new 3D modelling method combining the information at boreholes and the slopes derived from the EM resistivity model yielded an accurate model of the top of the chalk. All of this work provides a solid framework for future geo-environmental studies using airborne TDEM data, even in anthropized area.