Pendant des années, la recherche s'est principalement concentrée sur le soulèvement Andin de la Cordillère orientale de Colombie et sur l’étude des sédiments tertiaires dans les bassins sédimentaires pour comprendre la déformation andine. Récemment, la nécessité d'évaluer de nouvelles cibles a poussé l'industrie pétrolière à acquérir de nouvelles informations sur la série crétacée de la Cordillère Orientale (CO) et du cours moyen du Rio Magdalena (CMM). Le but de ce travail, est d'analyser ces données qui suggèrent que les sédiments du bassin du CMM ont été déformés au Crétacé.Les sédiments crétacés sont exposés dans la CO, mais seuls quelques affleurements sont connus dans le CMM. En revanche, beaucoup les informations de nombreuses lignes sismiques et de quelques puits traversant les unités crétacées sont disponibles sur cette zone. L’interprétation de quelques lignes sismiques sélectionnées du CMM a été contrôlée par les données de puits et et les observations de terrain, et la nature et le style des déformations observées ont été analysées. De cette façon, des discontinuités importantes et des structures tectoniques ont été identifiées, montrant que des failles ont été inversées tectoniquement par à-coups au Crétacé, avant l'orogenèse andine. Cette vision détaillée de l’évolution tectonique et sédimentaire de la série crétacée, surtout dans le CMM, met en évidence des discordances multiples résultant de multiples phases de déformation, de soulèvement et/ou de variations du niveau marin survenant au cours du Crétacé. Ceci est important pour comprendre les processus affectant la marge andine au Crétacé, puisque les interactions entre tectonique et variations eustatiques pourraient avoir été plus complexes que proposé antérieurement.L’analyse des traces de fission sur zircon et apatite et la modélisation thermique du Nord au Sud de la zone d'étude ont été faites sur des échantillons du Crétacé indiquant l'occurrence de deux événements thermiques et deux événements de refroidissement pour des unités anté-Campaniennes, et d'un réchauffement et d’un refroidissement pour les unités postérieures à ~ 70 Ma. Enfin, un régime de subduction cyclique pourrait expliquer les événements tectoniques extensifs et compressifs responsable des phases de dépôt, d'exhumation et d'érosion observées dans le CMM et l’OCO entre le Jurassique terminal et le Paléocène.L'analyse réalisée à l'aide de la stratigraphie et des cartes de faciès génère au chapitre 3, L'interprétation structurelle, chronostratigraphie en utilisant des diagrammes de roues, restauration structurelle schématique, permettant de reconnaître plusieurs cycles de dépôt (S1 à S5) limités par discordances (SU1 à SU5), sont le résultat de la fluctuation du niveau de la mer (cycles de régression-transgression) générée pour les événements tectoniques liés au régime de subduction des dalles. / For years, studies have been mainly focused on the Andean uplift of the Eastern Cordillera in Colombia and on the evaluation of the Tertiary units in sedimentary basins, in order to understand the recent deformation. Recently, due to the necessity oil industry to evaluate new targets, new information has been acquired on Cretaceous units form the Eastern Cordillera (EC) and the Middle Magdalena Valley (MMV). The aim of this work, is to analyses these data, which provide evidences for Cretaceous deformation in the basin of the MMV.Cretaceous sediments are exposed in the Eastern Cordillera, but only few outcrops are known in the MMV. Instead, a lot of seismic information is available and some drilled wells crosscut the Cretaceous units in this area. The interpretation of some key seismic sections in the MMV has been validated using field observation and well information, and the nature and style of the observed structures have been discussed. By these means, important Cretaceous unconformities and tectonic structures were identified, showing that some faults were progressively, tectonically inverted, prior to the Andean Orogeny. The resulting detailed picture of the Cretaceous tectonic and sedimentary evolution, especially in the MMV, evidences multiple unconformities resulting from different stages of deformation, uplift and/or level sea changes during the Cretaceous. This must be kept in mind to understand the processes acting in the Andean margin during the Cretaceous, since the interaction between deformation and sea level changes may have been more complex than previously thought.The fission tracks analyses on zircon and apatite and the thermal modeling from the North to the South of the study area were made on Cretaceous samples indicate the occurrence of two heating events and two events of cooling for pre-Campanian units, and of one event of heating and one event of cooling from units younger than ~ 70 Ma. Finally, a cyclic subduction regime may explain the tectonic extension and compression events responsible for the deposition, exhumation and erosion phases observed in the MMV and WEC from the latest Jurassic to the Paleocene.The analysis made using stratigraphy and the facies maps generate in chapter 3, The structural interpretation, chronostratigraphy chart using wheeler diagrams, schematic structural restauration, permit to recognize several cycles of deposition (S1 to S5) limited by unconformities (SU1 to SU5), which are the result of sea level fluctuation (Regression-Transgression cycles) generated for the Tectonic events related to the regimen of slabs subduction.

Late Ordovician Red River strata of southeastern Saskatchewan were deposited in a broad epicontinental sea. In the lower part, the Yeoman and Herald formations comprise two cycles of carbonateevaporite sequences. Although these units possess an overall layer-cake aspect, thickness variations especially in the Herald Formation show that accumulation was affected by syndepositional flexure, differential subsidence and displacement of fault-bounded blocks. The mainly laminated dolomudstones and anhydrites of the Lake Alma and Coronach members of the Herald Formation were deposited under relatively tranquil conditions. These units host different kinds of synsedimentary deformation features, interpreted to have been induced by earthquakes generated because of movements along basement faults thought to have been oriented orthogonally NE−SW and NW−SE. The low-energy environmental setting was conducive to preserving these features, referred to as seismites.<p> The variety of seismites in the Herald Formation is related to the varying rheology of the carbonate or evaporite sediment, as well as shaking intensity. Brittle and quasi-brittle failure is represented by faults, microfaults, shear-vein arrays and pseudo-intraclastic breccias, mostly in dolomudstones which must have been stiff at the time of deformation. Plastic behaviour is recorded by soft-sediment deformation, comprising a family of features that includes loop bedding, folded laminae and convolute bedding. Indeed, these structures in enterolithic anhydrite are more reasonably interpreted as due to deformation than crystal growth, volume expansion and displacement, the more usual explanations. Sediment shrinkage and concomitant fluidization are recorded by dikelets containing injected carbonate mud or granular gypsum, the latter now preserved as anhydrite. Evidence for wholesale liquefaction, however, was not observed. These rheological differences were caused by the primary nature of the sediment plus modifications due to early diagenesis and burial confinement. Shaking intensity is difficult to gauge, but it is presumed that a minimum of VI on the modified Mercalli scale was required to produce these features. Consequently, shaking of lesser magnitude was probably not recorded.<p> The geographic distribution of seismites should reflect the location of basement faults presumed to have been active during deposition, and indeed there is a concentration adjacent to the known location of syndepositonal fault lineaments. In addition, the stratigraphic distribution of seismites records higher frequencies of activity of these same faults. These distributions show that earthquake-induced ground motion was common during deposition of the Lake Alma Member in southeastern Saskatchewan but less so during deposition of the Coronach Member.<p> Seismites serve as proxies for the activity of relatively nearby syndepositional faults making up the tectonic fabric of sedimentary basins. They also point to basement features that, if re-activated, can induce fracture porosity or influence subsurface fluid flow. Syndepositional tectonism undoubtedly had a much more profound influence on many successions than is presently accepted, and its effects are more widespread than currently appreciated.

Paleochannels are a major cause of roof failure in underground coal mines in southeastern Kentucky. Models that predict the location and geometry of paleochannels are essential to assist in mine planning and development. Data from approximately 506 coal exploration drill holes were subjected to second-order trend-surface analysis to identify stacking or offsetting relationships between sandstone bodies in adjacent stratigraphic intervals. The stacking of sandstone bodies within adjacent intervals suggests the presence of synsedimentary faulting. This model suggests that continued movement along the faults created topographic lows attracted paleodrainages and accommodated thick accumulations of sandstone in approximately the same areas through time. Trend-surface residuals analysis successfully located areas of potential synsedimentary faulting within the study area. An additional 7,189 elevation data points for the top of the Newman Limestone, interpreted from oil and gas records, were utilized to locate sub-Pennsylvanian System faults within the study area. The correlation between faults associated with the coal measures identified using second-order trend-surface analysis and faults affecting the Newman Limestone suggests Pennsylvanian synsedimentary faults were preceded by older Paleozoic fault movement. The greater availability of oil and gas subsurface data makes this relationship an important tool for predicting locations of fault-controlled coal measure paleochannels.

Orientador: Lucas Veríssimo Warren / Resumo: O evento de ruptura do Gondwana no Cretáceo foi responsável pela reativação de estruturas do Pré-Cambriano e geração de diversas bacias interiores do tipo rifte no Nordeste do Brasil. Nesse contexto, a sucessão sedimentar da Bacia do Araripe registra as sequências pré-, sin- e pós-rifte formadas durante os distintos estágios tectono-sedimentares envolvidos na formação do Oceano Atlântico Sul. A Formação Araripina do Albiano Médio faz parte da sequência pós-rifte, é limitada na base por discordância litológica com rochas do embasamento ou por discordância angular com a Formação Romualdo, marinha. No topo, é limitada por discordância erosiva ou angular com os depósitos fluviais da Formação Exu. A Formação Araripina é composta principalmente de intercalações rítmicas de arenitos e lamitos, e a sucessão sedimentar é dividida em duas sequências deposicionais, SD1 e SD2, por uma superfície de truncamento regional. Sob essa superfície tectônica, em SD1, a associação de fácies mostra que a sedimentação foi em planícies intermediárias a distais de sistemas fluviais distributivos sujeitas a inundações episódicas associadas a canais efêmeros e à fluxos laminares, com evidências de complexos de splays terminais e laterais, pequenos lagos efêmeros e tectônica ativa. Acima da superfície, a SD2 apresenta menor evidência de tectonismo e de aporte sedimentar. O ambiente deposicional imediatamente após a superfície é compatível com depósitos de playa lake em diversos afloramentos estudados, pr... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Cretaceous Gondwana breakup event was responsible for the reactivation of Precambrian structures producing several interior rift basins in the Northeast Brazil. In this context, the sedimentary succession of the Araripe Basin record the pre, syn and post-rift sequences formed during the distinct tectono-sedimentary stages involved in the formation of the South Atlantic Ocean. The Middle Albian Araripina Formation is part of the post-rift sequence, bounded at base by basement rocks (nonconformity) or by the marine Romualdo Formation (angular unconformity). It is bounded at the top by a disconformity/angular unconformity with the fluvial deposits of the Exu Formation. The Araripina Formation is mainly composed of rhythmically interbedded sandstones and mudstones, and the succession is divided in two (DS1 and DS2) by a major truncating surface. Under this tectonic surface, in DS1, facies association shows that sedimentation was likely in a plain with medial to distal distributive fluvial systems. This plain was subjected to episodic inundations associated with ephemeral channels and sheetfloods, with evidences of terminal splays complexes, lateral splays, small playa lakes and active tectonics. Above the surface, the DS2 presents a more lenient tectonic setting and less sediment suppy. The depositional environment immediately after the surface is compatible with playa lake deposits in several studied places, probably in response to the previous tectonic activity. Overall, it... (Complete abstract click electronic access below) / Mestre