Un des objectifs de la restauration structurale, sujet de cette thèse, est de mettre en évidence les défauts d'interprétation ou les zones potentiellement fracturées. L'extension de cette technique en volume nécessite la définition a priori des propriétés des matériaux utilisés, notamment lorsque ces propriétés sont définies à une échelle fine. Une première partie, ce travail propose une méthode de mise à l'échelle des propriétés mécaniques utilisées pour les calculs de restauration en volume. La principale hypothèse repose sur la loi de comportement utilisée pour les matériaux définis à l'échelle grossière, supposés isotropiques transverses élastiques. Le calcul des propriétés équivalentes se fait par identification, après simulation par Éléments Finis. Cette technique a l'avantage d'assurer la conservation de l'énergie pour le même type de chargement. Dans une dernière partie, ce travail traite la gestion de la tectonique salifère lors de la restauration structurale. Les diapirs de sel présentent des topologies, des rhéologies, et des séquences de dépôt très caractéristiques. Ce mémoire présente une méthodologie de restauration multi-cartes, dont la prise en compte des relations inter-horizons est respectée dans les séquences halocinétiques. Une application de cette méthode est présentée sur le bassin de La Popa (Mexique) où les différentes interprétations réalisées au travers de leurs restaurations sont comparées / Structural restoration of geological models is undertaken to evaluate the geometrical and geological coherency of an interpretation. It can be used to determine deformation rates in different tectonic regimes. In addition, this technique has been used to evaluate high strain zones, and thus, potential fractured zones. Structural restoration attempts to reverse the effects of deformation history to an assumed initial pre-deformation state. Volumetric restoration techniques generally employ entirely continuum mechanic methods. The continuum mechanic model behaviors are dependent on the definition of the materials for which it is imposed reversibility by using elasticity behavior laws. This property is chosen based upon the predominant rock type in the fault block, generally at small scales. To overcome this issue, a methodology to upscale elastic isotropic materials has been implemented by treating upscaled materials as elastic transversely isotropic materials. This insures energy conservation for the same types of loading. Another focus of this work has been the management of salt tectonics in restoration procedures. A multi-surfaces restoration methodology has been developped based on the conservation of apparent thicknesses between stratigraphic layers and an iso-parametric restoration. This technique avoids the dependence of the volumetric restoration on a material model, while properly treating the restoration of unconformities and halokinetic sequences that characterize the flanks of salt structures. This technique has been tested on a field data set over a salt-withdrawal basin in the La Popa Basin (northeastern Mexico)

This thesis contains several distinct studies aimed at better understanding fracturing in compressional fault-cored folds. At outcrops of growth strata in the Oliana anticline in the Spanish Pyrenees, the relationship of two joint sets may reflect changing mechanical properties (i.e. via diagenesis) during the folding process. Using a Schmidt hammer, I assess the rigidity contrast between the individual units and suggest that late-stage, throughgoing joints formed in strata with conditions similar to those of the present day and that early, bed-contained joints formed when the rigidity contrast between beds was significantly greater than the present day contrast. Modeling algorithms that are used for fracture prediction assume plane strain to construct, model and restore fault-cored folds. Using mechanical models that allow heterogeneous transport in three dimensions, I explore the distribution and magnitude of out-of-plane transport in plunging fault-cored anticlines and provide guidelines of where plane strain should and should not be applied. I show that out-of-plane transport is significant in the simplest non-cylindrical folds, and suggest that complex non-cylindrical structures should not be modeled using plane strain. I mapped five bed-orthogonal fracture sets associated with folding and faulting events at Sant Corneli anticline, a non-cylindrical, fault related anticline in the Spanish Pyrenees. Fold axis perpendicular, calcite healed joint sets associated with similarly oriented normal faulting both pre-date, and are cross cut by calcite healed, N-NW striking joints. Later bed strike oblique joint sets are distinguished by the presence of iron oxide mineralization that probably occurred during Paleocene-Oligocene time. This study directly links fold-related fracturing to fold evolution because fracture sets can be dated relative to the structural evolution of the anticline. I use three-dimensional restorations of Sant Corneli anticline in the Spanish Pyrenees to test the fracture prediction capability of a fully three-dimensional finite element geomechanical restoration algorithm. Reconstruction of the three-dimensional architecture of the syn-tectonic strata provides a template for incrementally unfolding the anticline. Strains predicted by the restorations are compared to the fracture sets that formed over the corresponding time intervals, which are consistent with the observed fracture patterns at Sant Corneli anticline.

The present thesis consists in a real complex case study of halotectonic deformation in the central portion of the Santos Basin passive margin, investigating the complex interactions between deformation and sedimentation and evaluating its impacts on the petroleum systems.Seismic data set and exploration wells were input to the study, which cover an area where halokinetics affect the active petroleum systems. The thickest depocenter of the Santos basin is partially in the study area. The sedimentary infilling history is associated with the Cabo Frio Fault development, linked with a gap of tens of kilometers in the Albian sediments occurrence. Minibasins are under halotectonic compression towards deep waters. The challenges of this work consists in find methods to build and then to restore the structural model in an effective way.Fifteen interpreted horizons were used to build a surface model. Five geological cross-sections were restored and interpolated to get salt and overburden volumes. The restoration successively removes the uppermost layer and decompacts the remaining layers through sedimentary unloading. Restoration also considers the unloading isostatic compensation by flexure of an elastic weak layered lithosphere. The isostasy plays an important role in the tectono-sedimentary control. Its interaction with bathymetry, faults geometry and deposition surface profile constrains the local and regional subsidence. Biostratigraphic data and seismic pattern defined trough time the absolute paleobathymetry.The cross-section restoration has differentiated the major rift phase sequence deformation from three other drift phase sequences above the sal layer.Several 1D geo-histories were reconstructed for different points along the main direction of transport, to control the thickness variations in the 2D sections. 1D and 2D restorations clearly show that salt moves out of the study area and that there is strong coupling between the halotectonic dynamic and the change in the accommodation space.The extrapolation of the restoration results to 3D allows a better compartmentalization between the hemigrabens in the rift phase; highlights the role of structural high in the center of the investigated area and confirms the relation between structural evolution and sedimentation. Two major depocenters were amalgamated by salt deposition over the accentuated relief inherited from the larger vertical tectonic subsidence of the rift phase. The sedimentary infilling reveals the temporal relations of NE-SW and NNW-SSE oriented structures within the higher subsidence compartment in the western sector of the area. Two different ways to restore the sections allowed the uncertainty estimation of the bathymetry and isostatic relationships.The salt layer material conservation assumption, an operational tool, was consistent with the results. The salt volume balance over time showed a good correlation to lateral extension of the continental drift stage.The implications of the restoration scenario on the petroleum systems were only qualitatively interpreted and then compared to the classical backstripping approach. Three main sectors appear: the proximal shelf, the slope and the deepwater sector of the continental rise. The relatively early halotectonics of the proximal sector induces a more fast and short generation whereas, beyond the continental slope region, the petroleum systems is distally more heterogeneous, develops slower, dissipated and differentiated by the halokinesis, with longer refills fronts. The direct impact of salt restoration on the maturity evaluation is actually relatively small, because about 90% of ductile deformation occurred before 65 Ma and a significant part of the generation is ongoing after 65 Ma. On the other hand, the halotectonic restoration is fundamental regarding its impact on the petroleum systems. / Ce travail étudie la déformation salifère dans la partie centrale du Bassin de Santos sur la marge Atlantique brésilienne et examine l'interaction complexe entre cette déformation et la sédimentation, ainsi que ses effets sur les systèmes pétroliers. Les données sismiques et les puits disponibles couvrent une zone où l'halocinèse affecte les systèmes pétroliers actifs. Le principal dépôt-centre du bassin est partiellement dans la zone d'étude. L'histoire de remplissage sédimentaire est liée au développement de la faille de Cabo Frio, qui induit un absence des sédiments de l'Albien sur des dizaines de kilomètres. Des mini-bassins dus à la compression salifère se produisent dans la partie la plus distale.Il s'agit dans ce travail de trouver une méthode effective de construire et de restaurer le modèle structural. Quinze horizons stratigraphiques ont été interprétés. Cinq coupes géologiques ont été restaurées et interpolées pour analyser l'évolution temporelle des volumes du sel et des unités encaissantes. La restauration enlève successivement la couche la plus récente et décompacte les couches sous-jacentes en fonction de la charge enlevée. La procédure de restauration prend aussi en compte la compensation flexurale d'une lithosphère élastique et peu épaisse. L'isostasie joue un rôle important dans le contrôle tectono-sédimentaire. Son interaction avec la profondeur d'eau, la géométrie des failles et la surface de dépôt contrôle la subsidence locale et régionale. Des données des puits et les facies sismiques aident à calibrer la paléo-profondeur d'eau.La restauration de coupes différencie la déformation verticale de la phase anté sel des trois autres séquences qui ont été déposées au-dessus du sel. Plusieurs reconstructions 1D illustrent différentes situations le long de la direction principale de transport et permettent de contrôler l'épaisseur des coupes restaurées. Les restaurations 1D et 2D ont clairement montré que le sel s'échappe vers l'est au-delà de la région d'étude. La dynamique du sel se corrèle fortement avec l'espace d'accommodation disponible. L'extrapolation de la restauration au domaine 3D a permis de mieux configurer les demi-grabens de la phase rift, a accentué le rôle des hauts structuraux au centre de la zone étudiée et a montré comment les relations structurales contrôlent la sédimentation. Deux dépôt-centres ont été unis par le déposition de sel sur une topographie escarpée héritée du rifting. Le remplissage du compartiment le plus subsident à l'ouest du modèle a permis des interprétations temporelles par rapport aux structures orientées NE-SW et NNW-SSE. Deux façons de restaurer les coupes ont permis d'évaluer l'incertitude sur la paléo-profondeur d'eau et ses relations avec l'isostasie. L'hypothèse d'une préservation volumique du sel s'est avérée cohérente avec les résultats, puisqu'elle a montré une bonne corrélation avec la distension latérale lors de la dérive continentale.Les implications du scénario restauré sur les systèmes pétroliers ont été interprétées qualitativement et comparées ensuite avec l'approche classique de backstripping. Trois secteurs sont distingués : plateforme, pente et l'eau profonde. La tectonique salifère relativement précoce a induit une génération plus rapide et plus courte pour le secteur plus proche tandis que, au-delà de la pente continentale les systèmes pétroliers distaux sont plus hétérogènes avec un développement ralenti, dissipé et différencié par l'halocinèse, avec de recharges sur des temps plus longs. L'impact direct de la restauration de sel sur l'évaluation de la maturité est relativement faible, puisque 90% de la déformation ductile se produit avant 65 Ma et une partie importante de roches mères ont maturé plus tard. Mais la restauration de la tectonique salifère est essentielle par son impact sur le système pétrolier post déformation.

Este trabalho foi feito com dados de campo da Bacia de Benguela, na costa sul de Angola. Nesta área aflora uma plataforma carbonática de idade albiana, análoga às formações produtoras de petróleo de mesma idade na Bacia de Campos. Duas unidades principais compõem a seção albiana na área: uma unidade inferior caracterizada por carbonatos de águas rasas com intercalações de conglomerados e arenitos na base, totalizando 300 m de espessura total, e uma unidade superior formada por sedimentos carbonáticos de águas mais profundas com espessura de 100 m. Esta seção se apresenta em dois domínios estruturais. O norte é caracterizado por uma plataforma de cerca de 5 km de largura, 35 km de comprimento na direção NE e que se encontra próxima ao embasamento. No domínio sul, essa plataforma se apresenta em fragmentos de menos de 10 km de comprimento por até 5 km de largura, alguns deles afastados do embasamento. Dado que há evaporitos sob essa plataforma, fez-se este trabalho com o objetivo de se avaliar a influência da tectônica salífera na estruturação das rochas albianas. A utilização de imagens de satélite de domínio público permitiu a extrapolação dos dados pontuais e a construção de perfis topográficos que possibilitaram a montagem das seções geológicas. Os dados de campo indicam que a estruturação na parte norte, onde há menos sal, é influenciada pelas estruturas locais do embasamento. Já na parte sul, onde a espessura de sal é maior, a deformação é descolada das estruturas do embasamento. Foi feita uma seção geológica em cada domínio e a restauração dessas duas seções mostrou que a unidade albiana na parte sul sofreu uma distensão de 1,25 (125%) e a de norte se distendeu em 1,05 (105%). Essa diferença foi causada por uma maior espessura original de sal na parte sul, que fez com que a cobertura albiana se distendesse mais em consequência da fluência do sal mergulho abaixo, em resposta ao basculamento da bacia em direção a offshore. A intensidade da deformação na parte sul foi tal que os blocos falhados perderam os contatos entre si, formando rafts. Este efeito foi reproduzido em modelos físicos, indicando que a variação na espessura original de sal tem grande influência na estruturação das rochas que o cobrem. As variações de espessura de sal são controladas por zonas de transferência do embasamento e estas mesmas estruturas controlam os limites dos blocos que sofrem soerguimento diferencial no Cenozoico. / The present work was done with field data from Benguela Basin, which is located in the southern coast of Angola. At this site, an albian carbonatic platform, analogous to the hydrocarbon productive formations of the same age in Campos Basin, outcrops near the coast line , in the surroundings of the city of Benguela. Two major units are recognized among this section: The lower one is characterized by shallow water carbonates with sandstones and conglomerates interlayered at its basal levels, and a total thickness of 300 m. The upper section is composed of deep waters carbonate rocks in a 100 m thick package. This section occurs in two structural domains. The northern domain forms a 5 km wide and 35 km long platform elongated in the NE direction and close to the basement to the east. The southern part is represented by less than 10 km long and up to 5 km wide fragments, some of them displaced from the basement. Considering that evaporates underlie this platform, the main objective of this work is to investigate the influence of salt tectonics on the deformation of the albian rocks. The use of satellite images of public domain allowed the extrapolation of punctual information as well as the construction of the elevation profiles, utilized for the elaboration of the geologic sections. The field data indicate that the structuration at the northern domain, where there is less salt, is influenced by the basement structures. On the other hand, at the southern region, where the evaporitic section is thicker, the deformation is detached from the basement. One geologic section was constructed for each domain and their restorations indicated that the southern part of the platform was affected by an extension of 1,25 (125%) and that the extension at the northern part was 1,05 (105%). This variation is due to a thicker salt layer under the southern part, which conducted the albian package to extend more intensively in consequence of the downdip salt flow, when the basin was tilted toward the ocean. At this region extension was so intense that the faulted blocks lost contact with each other, forming the so called rafts. This effect was simulated in sand box models which indicated that the salt thickness plays a major role in the deformation of the overburden rocks. The variations on the original salt thickness was controlled by transfer faults in the basement and these are the same structures that controlled the boundaries of the basement blocks that responded differently to the Cenozoic uplift events

Este trabalho foi feito com dados de campo da Bacia de Benguela, na costa sul de Angola. Nesta área aflora uma plataforma carbonática de idade albiana, análoga às formações produtoras de petróleo de mesma idade na Bacia de Campos. Duas unidades principais compõem a seção albiana na área: uma unidade inferior caracterizada por carbonatos de águas rasas com intercalações de conglomerados e arenitos na base, totalizando 300 m de espessura total, e uma unidade superior formada por sedimentos carbonáticos de águas mais profundas com espessura de 100 m. Esta seção se apresenta em dois domínios estruturais. O norte é caracterizado por uma plataforma de cerca de 5 km de largura, 35 km de comprimento na direção NE e que se encontra próxima ao embasamento. No domínio sul, essa plataforma se apresenta em fragmentos de menos de 10 km de comprimento por até 5 km de largura, alguns deles afastados do embasamento. Dado que há evaporitos sob essa plataforma, fez-se este trabalho com o objetivo de se avaliar a influência da tectônica salífera na estruturação das rochas albianas. A utilização de imagens de satélite de domínio público permitiu a extrapolação dos dados pontuais e a construção de perfis topográficos que possibilitaram a montagem das seções geológicas. Os dados de campo indicam que a estruturação na parte norte, onde há menos sal, é influenciada pelas estruturas locais do embasamento. Já na parte sul, onde a espessura de sal é maior, a deformação é descolada das estruturas do embasamento. Foi feita uma seção geológica em cada domínio e a restauração dessas duas seções mostrou que a unidade albiana na parte sul sofreu uma distensão de 1,25 (125%) e a de norte se distendeu em 1,05 (105%). Essa diferença foi causada por uma maior espessura original de sal na parte sul, que fez com que a cobertura albiana se distendesse mais em consequência da fluência do sal mergulho abaixo, em resposta ao basculamento da bacia em direção a offshore. A intensidade da deformação na parte sul foi tal que os blocos falhados perderam os contatos entre si, formando rafts. Este efeito foi reproduzido em modelos físicos, indicando que a variação na espessura original de sal tem grande influência na estruturação das rochas que o cobrem. As variações de espessura de sal são controladas por zonas de transferência do embasamento e estas mesmas estruturas controlam os limites dos blocos que sofrem soerguimento diferencial no Cenozoico. / The present work was done with field data from Benguela Basin, which is located in the southern coast of Angola. At this site, an albian carbonatic platform, analogous to the hydrocarbon productive formations of the same age in Campos Basin, outcrops near the coast line , in the surroundings of the city of Benguela. Two major units are recognized among this section: The lower one is characterized by shallow water carbonates with sandstones and conglomerates interlayered at its basal levels, and a total thickness of 300 m. The upper section is composed of deep waters carbonate rocks in a 100 m thick package. This section occurs in two structural domains. The northern domain forms a 5 km wide and 35 km long platform elongated in the NE direction and close to the basement to the east. The southern part is represented by less than 10 km long and up to 5 km wide fragments, some of them displaced from the basement. Considering that evaporates underlie this platform, the main objective of this work is to investigate the influence of salt tectonics on the deformation of the albian rocks. The use of satellite images of public domain allowed the extrapolation of punctual information as well as the construction of the elevation profiles, utilized for the elaboration of the geologic sections. The field data indicate that the structuration at the northern domain, where there is less salt, is influenced by the basement structures. On the other hand, at the southern region, where the evaporitic section is thicker, the deformation is detached from the basement. One geologic section was constructed for each domain and their restorations indicated that the southern part of the platform was affected by an extension of 1,25 (125%) and that the extension at the northern part was 1,05 (105%). This variation is due to a thicker salt layer under the southern part, which conducted the albian package to extend more intensively in consequence of the downdip salt flow, when the basin was tilted toward the ocean. At this region extension was so intense that the faulted blocks lost contact with each other, forming the so called rafts. This effect was simulated in sand box models which indicated that the salt thickness plays a major role in the deformation of the overburden rocks. The variations on the original salt thickness was controlled by transfer faults in the basement and these are the same structures that controlled the boundaries of the basement blocks that responded differently to the Cenozoic uplift events

L'objectif de cette thèse est d'expliquer les avantages qu'offrent la reconstruction de l'architecture des unités géologiques, leurs déformations ainsi que leurs variations au cours du temps à l'exploration de ressources minérales, tout en appliquant des méthodes et outils de modélisation 3D et 4D. La modélisation et la restauration structurale sont utilisées ici pour estimer des attributs géologiques qui peuvent aider à la compréhension de la formation des gisements, et à l'identification des zones favorables aux minéralisations. Cette thèse est axée sur l'application de la modélisation 3D et 4D à des cas réels pour trouver le lien entre une minéralisation et des processus géologiques tel que l'exhumation des terrains, l'activité des failles et la fracturation résultant d'un évènement de déformation. Ce mémoire est organisé en trois parties : (i) la modélisation structurale ainsi que la restauration surfacique ont été appliquées au district minier de la Ceinture de Cuivre de Legnica-Glogów (sud-ouest de la Pologne), pour estimer les conditions favorables à la fracturation hydraulique. Cette fracturation est intervenue dans le nord de l'Europe lors d'une phase d'inversion à la fin du Crétacé et au début du Paléocène. Dans notre hypothèse de départ, la fracturation hydraulique développée au cours de cette période a joué un rôle important dans la distribution en cuivre observée aujourd'hui dans le district minier ; (ii) la courbure des surfaces triangulées, représentant les horizons de la région des Sudètes polonaises, permet de mettre en évidence les systèmes de failles dans le socle. En particulier, des méthodes de restauration surfaciques ont été utilisées pour évaluer l'activité de des failles au cours du temps, en se basant sur la courbure des surfaces obtenues à chaque étape de la restauration. Les zones de fortes activités sont ici associées aux processus de minéralisation cuprifère de la région ; (iii) la restauration mécanique de la région de Mount Pleasant (Australie occidentale), a permis de simuler un évènement de raccourcissement apparu dans l'Archéen et qui est lié à un processus de minéralisation aurifère. La restauration mécanique est appliquée pour estimer le champ des déformations de la région au moment du raccourcissement. Avec ce champ de déformation, il est possible de calculer les paramètres d'endommagement de la masse rocheuse qui semblent liés aux zones aurifères situées hors des systèmes principaux de failles. Cette thèse a ainsi permis de mettre en évidence l'aspect prometteur de la modélisation et de la restauration structurale pour identifier des zones potentiellement minéralisées, mettant en valeur leur utilisation pour l'exploration des gisements et des ressources minérales / The objective of this Ph.D. thesis is to apply 3D and 4D modeling methods to reconstruct the architecture and deformations over time of geological entities in a defined region. Structural restoration modeling is used here to estimate geological, physical and structural attributes for understanding the origin of ore-deposits, and for identifying potential mineralized areas. We focused this thesis on 3D and 4D modeling on real case studies with different geological contexts (e.g. uplifting, fault activity and shortening), demonstrating the advantages and drawbacks on their use for similar situations. This thesis is organized into three parts: (i) the application of structural modeling in the mining district of the Copper Belt of Legnica-Glogów (south-west Poland). A surface-restoration approach was applied to estimate favorable conditions for hydraulic fracturing during an inversion, occurred in the northern part of Europe at Late Cretaceous--Early Paleocene. In our hypothesis, hydraulic fracturing developed at that time played an important role in the distribution of copper content observed in present days in the mining district. (ii) The curvature calculated on triangulated surfaces that represent the stratigraphic horizons in the Fore-Sudetic region (Poland), are used to highlight the fault systems in the basement as well as their activity. High curvature values reveal the fault activity which is associated with the copper mineralization process in the region. (iii) Mechanical restoration of the Mount Pleasant, Western Australia, simulates an Archean shortening event which occurred in the area linked to the gold mineralization process. The mechanical restoration was used to estimate the strain field in the region at the time of shortening. This deformation field was used to estimate the damage parameters of the rock mass. They show new potential gold areas located in off-fault gold systems. In conclusion, it is shown that 3D modeling and structural restoration could be used to identify potential favorable zones for the presence of mineralization, and seem promising as a tool for the exploration of ore-deposits and mineral resources