This study provides the most updated stratigraphic, depositional and diagenetic histories of the Early Cretaceous Biyadh and Shu'aiba formations. Carbon isotope data were integrated with core descriptions and well logs to define the age model beyond the resolution of biostratigraphy; they were also used as a geochronology tool for correlating between wells and across platform to basin transitions. The Biyadh Formation consists of one 3rd-order sequence of four high-frequency sequences (S1-S4). S1 and S2 are the TST, composed of deep chalky limestone facies. S3 and S4 are the HST composed of skeletal rudist grainstone deposited in shallow water environments. The Biyadh sequence is capped by a regional subaerial boundary (SB1) corresponding to a global sea level fall. The Shu'aiba Formation consists of one 2nd-order sequence of four 3rd-order sequences and ten HFS's (S1-S10). S1 records the initial TST, followed by the regional MFS (K70) of S2. S3 is the late TST and is dominated by Lithocodium aggregatum/coral facies. S4 to S6 formed the early HST and are dominated by rudist buildups that transitioned basinward into fore-bank, slope and basinal settings with pronounced clinoform geometries. S7 and S8 are composed of shallow lagoonal milliolid packstone, representing the late HST. S9 and S10 are new identified Upper Aptian prograding sequences that formed during forced regression on the northern-block within platform edge and slope settings. The correlation between the Arabian Plate stratigraphic record and the standard Tethys isotope record and eustatic sea-level suggests a direct influence of the 3rd-order sea-level fluctuations on the Biyadh and Shu'aiba formations. This correlation also suggests that the Aptian were mainly controlled by glacio-eustatic fluctuations associated with eccentricity cycles. The Barremian records low magnitude sea-level changes and thinner sequences likely reflecting obliquity cycles. The Shu'aiba Formation records major subaerial hiatus reflecting glacial intervals, interrupted by flooding units reflecting global warming intervals. Trace elements, microprobe analysis, Cathodoluminescence (CL) and stable isotope data were used to define the diagenetic history of the Shu'aiba Formation within the sequence stratigraphic framework. The Shu'aiba Formation was mainly affected by meteoric diagenesis associated with the major unconformity at top of Shu'aiba.

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.