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Le Jurassique supérieur est une période qui présentait une paléogéographie et des conditions climatiques globales favorables au développement des systèmes sédimentaires dominés par les tempêtes. L’objectif de ce travail est de comprendre les facteurs contrôlant la dynamique de ces systèmes, ainsi que la relation entre les variations de fréquences et d’intensité des tempêtes et les changements climatiques. Trois coupes ont été choisies pour cette étude : les Pas (passage Oxfordien – Kimméridgien) et la coupe du Rocher d’Yves (Kimméridgien supérieur), près de La Rochelle ; la coupe du Cap de la Crèche (Kimméridgien supérieur – début du Tithonien), dans le Boulonnais. Ces coupes sont analysées pour la sédimentologie, les palynofaciès et les nannofossiles calcaires. Pour chacune d’elles, un modèle de faciès détaillé est établi, permettant de proposer une interprétation séquentielle et cyclostratigraphique précise. L’interprétation cyclostratigraphique permet d’interpréter les dépôts de tempêtes en terme de variations de fréquence des tempêtes. L’interprétation séquentielle permet de s’affranchir des variations du niveau marin relatif pour interpréter les dépôts de tempêtes en terme de variations d’intensité des tempêtes. Les points communs et les différences entre ces deux systèmes sont discutés, tant du point de vue de la dynamique sédimentaire que de l’enregistrement et de la préservation des dépôts de tempêtes. Enfin, la relation entre les variations de fréquence et d’intensité des tempêtes et les changements climatiques est discutée. Les faciès sédimentaires de La Rochelle et du Boulonnais présentent une organisation spatiale relativement similaire. La production carbonatée des systèmes présente des similitudes et des différences. Elle semble capable de réagir très rapidement aux variations du niveau marin relatif, augmentant avec l’élévation du niveau marin relatif. Les deux systèmes ont également une évolution similaire dans le temps. Les dépôts de tempêtes des deux sites montrent des morphologies similaires, liées aux conditions de dépôt et de préservation. Il a été possible de mettre en relation les variations d’intensité, de fréquences, et les changements du climat. Ainsi, les variations d’intensité des tempêtes semblent évoluer en parallèle des variations de fréquence, les valeurs d’intensité les plus élevées correspondant aux valeurs de fréquences les plus élevées. De plus, ces augmentations de fréquence et d’intensité ont lieu en même temps que l’augmentation des températures, indiquant un lien entre le réchauffement du climat et l’augmentation de l’activité des tempêtes / The Late Jurassic was a period with paleogeography and global climatic conditions that favor the development of sedimentary systems dominated by storms. The purpose of this study is to better understand the controlling factors on the dynamic of these systems. Three sections are chosen. The Pas (Oxfordian – Kimmeridgian transition) and the Rocher d'Yves (Late Kimmeridgian) sections, near La Rochelle (Western France), correspond to a muddy, mixed carbonated – siliciclastic platform. The Cap de la Crèche section (Late Kimmeridgian – Early Tithonian) corresponds to a mixed carbonated – siliciclastic ramp, dominated by coarse material. Sedimentary, palynofacies, and calcareous nannofossil analyses are performed. For each section, a detailed facies model is proposed, allowing precise sequence- and cyclostratigraphic interpretations. The sequence and cyclostratigraphic frameworks allow the calculation of the storm frequency. Comparison between host facies and storm deposits allows the estimation of storm intensity. The similarities and differences between these two systems are discussed, for the sedimentary dynamic, and the record and preservation of the storm deposits. Finally, the relation between storm frequency and intensity and climate is discussed. La Rochelle and Boulonnais sedimentary facies have a similar spatial organization. Carbonate production of these systems presents similarities and differences. The carbonate production seems able to react very quickly to relative sea-level variations, increasing when sea-level is high. The two systems also have a similar evolution in time. The storm deposits of the two sites show similar morphologies, related to the conditions of deposition and preservation. It was possible to link the variations of storm intensity and frequency with the climate changes. The variations of storm intensity evolve in parallel of the variations of storm frequency, the highest values of intensity corresponding to the highest values of frequency. Moreover, this increase in frequency and intensity is consistent with increasing temperature, suggesting a link between the increasing storm activity and the climate warming

Dans les réservoirs silicoclastiques, la perte de porosité avec l'enfouissement est due à la fois à la compaction mécanique lors des 2-3 premiers kilomètres d'enfouissement, à la compaction chimique, et à la précipitation minérale (quartz, argiles, carbonates). Dès lors, la compréhension des processus responsables de l'inhibition de la compaction et/ou de la cimentation représente un triple enjeu: i) contribuer à la connaissance des mécanismes d'interactions eau-hydrocarbures-solides en milieu diagénétique profond; ii) apporter de nouveaux arguments pour reconstituer les chemins de migration des fluides à l'échelle du bassin iii) développer des guides de prospection pour l'industrie pétrolière. Les techniques analytiques telles que la pétrographie quantitative, les inclusions fluides ainsi que les modélisations diagénétiques et de bassin ont été couplées afin de comprendre les processus régissant le contrôle de la qualité du réservoir du Brent (Jurassique Moyen) à travers 8 champs pétroliers (et 11 puits) dans le bloc Q3 (Viking Graben, Northern North Sea). L'étude pétrographique quantitative du réservoir du Tarbert a permis de définir des compositions minéralogiques et des paramètres pétrophysiques (porosité) relativement similaires sur les 183 échantillons étudiés. Une paragenèse diagénétique commune à tous les champs étudiés a été établie, dominée par les ciments de quartz, de deux générations de kaolinite (K1, associée à la déstabilisation des micas et K2, associée à la dissolution des feldspaths potassiques), et de précipitation d'illite. L'approche comparative des ciments d'enfouissement n'a pas permis de rendre compte des larges gammes de porosité et perméabilité mesurées allant de 8 à 27 % et de 0,2 à 5000 mD. Contrairement au modèle diagénétique souvent évoqué, l'inhibition des ciments de quartz ne joue pas un rôle majeur dans la préservation de la porosité des réservoirs du bloc Q3. Les estimations P-V-T-X-t du piégeage des inclusions fluides couplées au modèle de bassin ont permis de reconstituer trois chemins de migration des fluides aqueux et hydrocarbonés associés à la mise en place de surpressions fluides au sein des réservoirs du Tarbert. 1) La partie Nord de la kitchen du Viking Graben alimente les champs de Hild, Jura et Islay en huiles légères très précocement (65-42 Ma) et en gaz à condensat à partir de 35-15 Ma. Ces deux migrations sont associées à une montée en surpression fluide du réservoir de 100 à 200 bar. 2) la partie Est de la kitchen de l'East Shetland alimente les champs d'Alwyn, Dunbar, et Grant en huiles lourdes à légères à partir de 42-35 Ma, associée à une faible surpression fluide (30-40 bar). 3) la partie Sud de la kitchen de l'East Shetland (longue distance de migration) alimente quant à elle les champs de Forvie Central et North très tardivement en gaz à condensat (> 15 Ma). Le timing relatif entre la mise en place de la surpression fluide et l'avancement de la compaction mécanique/chimique s'est révélé être le paramètre de premier ordre régissant la préservation de la porosité des réservoirs observée dans le bloc Q3. La présence d'inclusions hydrocarbonées atypiques HT-BP (haute température-basse pression) datées du Jurassique supérieur dans les champs proches du Viking Graben, pourrait être à l'origine d'une génération d?hydrocarbures très précoce sous un régime de pression hydrostatique. Bien que n'ayant aucun impact sur l'inhibition de la contrainte effective, cette migration fluide pourrait être attribuée aux anomalies thermiques du Nord-Ouest de l'Europe liée à l'ouverture de l'Atlantique Nord. Le couplage des outils de pétrographie quantitative, inclusions fluides et modélisation de bassin a donc permis de soulever l'importance d'intégrer une vision régionale à l'étude ponctuelle de la diagenèse dans le but de comprendre le rôle des migrations fluides sur la préservation de la qualité des réservoirs silicoclastiques / In siliciclastic reservoirs, porosity loss is mainly due to the mechanical compaction in the first 2-3 km of burial, the chemical compaction and mineral precipitation (quartz, clays, carbonates). Therefore, understanding the processes responsible of the inhibition of compaction and/or cementation permits to: i) contribute to the knowledge of the water-hydrocarbon-solid interaction mechanisms in deep diagenetic environment, ii) give new arguments for the reconstruction of fluid pathways at the basin scale iii) assist the oil industry for the intensive exploration. Analytical techniques such as quantitative petrography, fluid inclusion and basin/diagenesis modelling were coupled across 8 oil fields (and 11 wells) located in the Q3 block (Viking Graben, Northern North Sea) in order to understand the processes driving the variation of the Brent reservoir quality (Middle Jurassic). Quantitative petrographic study of Tarbert reservoir allowed to define similar depositional settings (mineralogy, porosity) among the 183 studied samples. The common diagenetic paragenesis is dominated by quartz cement, two generations of kaolinite (K1, associated with the destabilization of micas and K2, associated with the dissolution of feldspars), and precipitation of illite. The petrographic data do not explain the wide range of measured porosity and permeability on plugs from 8 to 27% and from 0.2 to 5000 mD respectively. In contrast with the conventional diagenetic model, the present study shows that inhibition of quartz cements did not play a major role in the preservation of porosity in the Q3 block. P-V-T-X-t estimates of fluid inclusion trapping coupled with basin modelling allowed reconstruction of three fluid migration pathways, associated with fluid overpressures in the Tarbert reservoir. 1) The northern part of the Viking Graben kitchen supplies Hild, Jura and Islay fields with an early migration of light oils (65-42 m.y.) and condensate from 35-15 m.y. Both migrations are associated with a great fluid overpressure from 100 to 200 bar. 2) The eastern part of the East Shetland kitchen supplies Alwyn, Dunbar, Grant fields, with heavy to light oils from 42-35 m.y., associated with a low fluid overpressure (30-40 bar). 3) The southern part of the East Shetland kitchen (long distance migration) supplies Forvie North and Central fields with a very late gas condensate migration (> 15 Ma). The relative timing of the fluid overpressure build-up with the degree of mechanical and chemical compaction appears to be the first order parameter governing the preservation of reservoir porosity across the Q3 block. The presence of unusual HT-LP (high temperature-low pressure) hydrocarbon inclusions in the fields near the graben could indicate an early heavy oil generation under hydrostatic pressure conditions. Although having no impact on the inhibition of effective stress, this high-temperature fluid migration could be attributed to thermal anomalies in the Northwest of Europe related to the North Atlantic opening. The combination of quantitative petrography, fluid inclusion and basin modelling allowed to point out the impact of regional fluid migrations on the well scale diagenesis and on the siliciclastic reservoir quality preservation

A constante intercalação entre rochas siliciclásticas, carbonáticas e hibridas gerou complexos reservatórios de petróleo na seção albiana (Grupo Barra Nova) da plataforma de Regência, porção emersa da bacia do Espírito Santo. O principal objetivo do trabalho é compreender o ambiente deposicional da sucessão sedimentar mista carbonática-siliciclástica albiana do Grupo Barra Nova nesta área e os fatores que condicionam a qualidade dos seus reservatórios. As rochas que compõe a sucessão estudada foram caracterizadas como rochas siliciclásticas, compostas por mais de 2/3 de grãos siliciclásticos, rochas carbonáticas, compostas por mais de 2/3 de grãos aloquímicos, e rochas hibridas, que possuem entre 1/3 e 2/3 de grãos siliciclásticos, sendo o restante de aloquímicos. Os grãos siliciclásticos são angulosos, mal a moderadamente selecionados, ricos em feldspatos, granadas e pesados, derivados de depósitos de primeiro ciclo, indicando transporte e deposição rápidos. Os grãos carbonáticos se encontram retrabalhados, apresentando abrasão dos envelopes dos oncolitos. A presença constante de grãos carbonáticos, inclusive nas rochas siliciclásticas, indica que as fábricas carbonáticas de água rasa eram permanentemente atuantes durante toda a deposição da sucessão analisada. Fatores como a re-deposição dos grãos carbonáticos, a intercalação caótica entre rochas carbonáticas, siliciclásticas e híbridas além do domínio de rochas maciças indicam que a deposição ocorreu principalmente por fluxos gravitacionais. Apesar da alta frequência de intercalação, foi possível reconhecer sequencias através da correlação entre as fácies e os perfis elétricos. Sequencias de 4ª ordem foram definidas pelo empilhamento de siliciclásticos finos, gradando a siliciclásticos grossos, a arenitos híbridos, culminando em carbonatos no topo. Mudanças climáticas e a variação relativa do nível do mar (influenciado pela tectônica salífera) controlaram o domínio de depósitos carbonáticos ou siliciclásticos. Durante períodos secos e de mar alto, havia aumento da fábrica carbonática enquanto períodos úmidos e de nível de mar baixo o aporte de siliciclásticos era preponderante. / The constant intercalation between siliciclastic, carbonatic and hybrid rocks generated complex petroleum reservoirs in Albian section (Barra Nova Group) of Regencia platform, onshore portion of Espirito Santo Basin. The main purpose of this work is to understand the depositional environment of Albian Barra Nova Group mixed carbonate-siliciclastic sedimentary sequence and the main factors that control the quality of the reservoirs. The rocks that constitute the succession were characterized as siliciclastic rocks, composed of more of 2/3 of siliciclastic grains, carbonate rocks, composed of more of 2/3 of carbonate allochem grains, and hybrid rocks, composed of between 1/3 and 2/3 of siliciclastic, being the remaining carbonate grains. Siliciclastic grains are angular, badly to moderately sorted, rich in feldspars, garnets and other heavy minerals, derived from first-cycle deposits through fast transport and deposition. Carbonate grains are reworked, commonly showing abrasion of the envelopes of oncolites. The constant presence of carbonate grains, even in the siliciclastic rocks, shows that the shallow water carbonate factory was permanently in activity during the whole deposition of the succession. The re-deposition of carbonate grains, the chaotic interbedding between carbonate, siliciclastic and hybrid rocks, and the dominance of massive rocks indicate that gravity flows were responsible for the transportation of the sediments. Although for the high frequency of intercalation, depositional sequences were identified through the correlation between facies analysis and well logs. 4th order sequences were defined, beginning with fine siliciclastic, grading to coarse siliciclastic to the top, followed by hybrid arenites, and culminating in carbonates at the top. Climatic changes and eustatic variation (induced by salt tectonics) controlled the sedimentation of siliciclastics and carbonates. During dry periods with high sea level the domine were of carbonatic sedimentation while wet periods with low sea level the supply of siliciclastic were abundant.

A constante intercalação entre rochas siliciclásticas, carbonáticas e hibridas gerou complexos reservatórios de petróleo na seção albiana (Grupo Barra Nova) da plataforma de Regência, porção emersa da bacia do Espírito Santo. O principal objetivo do trabalho é compreender o ambiente deposicional da sucessão sedimentar mista carbonática-siliciclástica albiana do Grupo Barra Nova nesta área e os fatores que condicionam a qualidade dos seus reservatórios. As rochas que compõe a sucessão estudada foram caracterizadas como rochas siliciclásticas, compostas por mais de 2/3 de grãos siliciclásticos, rochas carbonáticas, compostas por mais de 2/3 de grãos aloquímicos, e rochas hibridas, que possuem entre 1/3 e 2/3 de grãos siliciclásticos, sendo o restante de aloquímicos. Os grãos siliciclásticos são angulosos, mal a moderadamente selecionados, ricos em feldspatos, granadas e pesados, derivados de depósitos de primeiro ciclo, indicando transporte e deposição rápidos. Os grãos carbonáticos se encontram retrabalhados, apresentando abrasão dos envelopes dos oncolitos. A presença constante de grãos carbonáticos, inclusive nas rochas siliciclásticas, indica que as fábricas carbonáticas de água rasa eram permanentemente atuantes durante toda a deposição da sucessão analisada. Fatores como a re-deposição dos grãos carbonáticos, a intercalação caótica entre rochas carbonáticas, siliciclásticas e híbridas além do domínio de rochas maciças indicam que a deposição ocorreu principalmente por fluxos gravitacionais. Apesar da alta frequência de intercalação, foi possível reconhecer sequencias através da correlação entre as fácies e os perfis elétricos. Sequencias de 4ª ordem foram definidas pelo empilhamento de siliciclásticos finos, gradando a siliciclásticos grossos, a arenitos híbridos, culminando em carbonatos no topo. Mudanças climáticas e a variação relativa do nível do mar (influenciado pela tectônica salífera) controlaram o domínio de depósitos carbonáticos ou siliciclásticos. Durante períodos secos e de mar alto, havia aumento da fábrica carbonática enquanto períodos úmidos e de nível de mar baixo o aporte de siliciclásticos era preponderante. / The constant intercalation between siliciclastic, carbonatic and hybrid rocks generated complex petroleum reservoirs in Albian section (Barra Nova Group) of Regencia platform, onshore portion of Espirito Santo Basin. The main purpose of this work is to understand the depositional environment of Albian Barra Nova Group mixed carbonate-siliciclastic sedimentary sequence and the main factors that control the quality of the reservoirs. The rocks that constitute the succession were characterized as siliciclastic rocks, composed of more of 2/3 of siliciclastic grains, carbonate rocks, composed of more of 2/3 of carbonate allochem grains, and hybrid rocks, composed of between 1/3 and 2/3 of siliciclastic, being the remaining carbonate grains. Siliciclastic grains are angular, badly to moderately sorted, rich in feldspars, garnets and other heavy minerals, derived from first-cycle deposits through fast transport and deposition. Carbonate grains are reworked, commonly showing abrasion of the envelopes of oncolites. The constant presence of carbonate grains, even in the siliciclastic rocks, shows that the shallow water carbonate factory was permanently in activity during the whole deposition of the succession. The re-deposition of carbonate grains, the chaotic interbedding between carbonate, siliciclastic and hybrid rocks, and the dominance of massive rocks indicate that gravity flows were responsible for the transportation of the sediments. Although for the high frequency of intercalation, depositional sequences were identified through the correlation between facies analysis and well logs. 4th order sequences were defined, beginning with fine siliciclastic, grading to coarse siliciclastic to the top, followed by hybrid arenites, and culminating in carbonates at the top. Climatic changes and eustatic variation (induced by salt tectonics) controlled the sedimentation of siliciclastics and carbonates. During dry periods with high sea level the domine were of carbonatic sedimentation while wet periods with low sea level the supply of siliciclastic were abundant.

A constante intercalação entre rochas siliciclásticas, carbonáticas e hibridas gerou complexos reservatórios de petróleo na seção albiana (Grupo Barra Nova) da plataforma de Regência, porção emersa da bacia do Espírito Santo. O principal objetivo do trabalho é compreender o ambiente deposicional da sucessão sedimentar mista carbonática-siliciclástica albiana do Grupo Barra Nova nesta área e os fatores que condicionam a qualidade dos seus reservatórios. As rochas que compõe a sucessão estudada foram caracterizadas como rochas siliciclásticas, compostas por mais de 2/3 de grãos siliciclásticos, rochas carbonáticas, compostas por mais de 2/3 de grãos aloquímicos, e rochas hibridas, que possuem entre 1/3 e 2/3 de grãos siliciclásticos, sendo o restante de aloquímicos. Os grãos siliciclásticos são angulosos, mal a moderadamente selecionados, ricos em feldspatos, granadas e pesados, derivados de depósitos de primeiro ciclo, indicando transporte e deposição rápidos. Os grãos carbonáticos se encontram retrabalhados, apresentando abrasão dos envelopes dos oncolitos. A presença constante de grãos carbonáticos, inclusive nas rochas siliciclásticas, indica que as fábricas carbonáticas de água rasa eram permanentemente atuantes durante toda a deposição da sucessão analisada. Fatores como a re-deposição dos grãos carbonáticos, a intercalação caótica entre rochas carbonáticas, siliciclásticas e híbridas além do domínio de rochas maciças indicam que a deposição ocorreu principalmente por fluxos gravitacionais. Apesar da alta frequência de intercalação, foi possível reconhecer sequencias através da correlação entre as fácies e os perfis elétricos. Sequencias de 4ª ordem foram definidas pelo empilhamento de siliciclásticos finos, gradando a siliciclásticos grossos, a arenitos híbridos, culminando em carbonatos no topo. Mudanças climáticas e a variação relativa do nível do mar (influenciado pela tectônica salífera) controlaram o domínio de depósitos carbonáticos ou siliciclásticos. Durante períodos secos e de mar alto, havia aumento da fábrica carbonática enquanto períodos úmidos e de nível de mar baixo o aporte de siliciclásticos era preponderante. / The constant intercalation between siliciclastic, carbonatic and hybrid rocks generated complex petroleum reservoirs in Albian section (Barra Nova Group) of Regencia platform, onshore portion of Espirito Santo Basin. The main purpose of this work is to understand the depositional environment of Albian Barra Nova Group mixed carbonate-siliciclastic sedimentary sequence and the main factors that control the quality of the reservoirs. The rocks that constitute the succession were characterized as siliciclastic rocks, composed of more of 2/3 of siliciclastic grains, carbonate rocks, composed of more of 2/3 of carbonate allochem grains, and hybrid rocks, composed of between 1/3 and 2/3 of siliciclastic, being the remaining carbonate grains. Siliciclastic grains are angular, badly to moderately sorted, rich in feldspars, garnets and other heavy minerals, derived from first-cycle deposits through fast transport and deposition. Carbonate grains are reworked, commonly showing abrasion of the envelopes of oncolites. The constant presence of carbonate grains, even in the siliciclastic rocks, shows that the shallow water carbonate factory was permanently in activity during the whole deposition of the succession. The re-deposition of carbonate grains, the chaotic interbedding between carbonate, siliciclastic and hybrid rocks, and the dominance of massive rocks indicate that gravity flows were responsible for the transportation of the sediments. Although for the high frequency of intercalation, depositional sequences were identified through the correlation between facies analysis and well logs. 4th order sequences were defined, beginning with fine siliciclastic, grading to coarse siliciclastic to the top, followed by hybrid arenites, and culminating in carbonates at the top. Climatic changes and eustatic variation (induced by salt tectonics) controlled the sedimentation of siliciclastics and carbonates. During dry periods with high sea level the domine were of carbonatic sedimentation while wet periods with low sea level the supply of siliciclastic were abundant.

L’évolution des systèmes sédimentaires jurassiques (Pliensbachien-Bajocien) dans le secteur de Zaouiat-Ahançal (Haut Atlas, Maroc) est localement influencée par des mouvements diapiriques associés à la ride du Jbel Azourki. Cette structure tectonique complexe suit un tracé en baïonnette d’orientation globale OSO-ENE sur près de 60 kilomètres, ponctué par six affleurements de matériel diapirique triasique. L’objectif de cette thèse est de caractériser l’impact du diapirisme sur la géométrie des dépôts et sur la distribution des faciès au sein de trois systèmes de dépôt successifs : (1) un système carbonaté de plate-forme peu profonde (Formations d’Aganane, de Jbel Choucht et d’Assemsouk) (2) des systèmes de rampe mixte silicoclastique et carbonatée (Formations de Tamadout, d’Amezraï, de Tafraout et d’Aguerd-n-Tazoult), (3) et un système carbonaté oolitique (Formation de Bin-El-Ouidane). Une cartographie détaillée des unités stratigraphiques et des unités de faciès, ainsi qu’une série de quatorze coupes géologiques de la ride diapirique du Jbel Azourki ont ainsi été réalisées. L’étude des interactions entre sédimentation et diapirisme révèle un enregistrement continu de la déformation diapirique sur l’ensemble de la série sédimentaire, et a permis d’établir une chronologie de l’activité diapirique dans le secteur de Zaouiat-Ahançal. L’unité des calcaires inférieurs (1) enregistre une déformation polyphasée marquée par le développement localisé, au sein de la plate-forme, de bassins d’extension kilométrique caractérisés par une sédimentation hémipélagique et gravitaire (rim basins). Ces bassins circonscrits aux diapirs sont limités par des bordures de plate-forme bioconstruites à Lithiotis, de type aggradant ou érosif. À partir du Pliensbachien terminal, les déformations syndiapiriques se manifestent dans les unités mixtes (2), d’une part à l’échelle plurikilométrique avec l’accumulation de plusieurs milliers de mètres de dépôts, contrôlée par la variation latérale du taux de subsidence entre et au sein des compartiments nord et sud de la ride, et d’autre part à l’échelle hectométrique de la bordure du diapir avec des géométries caractéristiques et des variations de faciès (micro plates-formes à oolites et coraux). La ride diapirique perce en surface pendant le dépôt des unités mixtes, puis est recouverte par l’unité transgressive peu déformée des calcaires supérieurs (3) à l’Aalénien terminal. Les paramètres de contrôle de la géométrie des dépôts et de la distribution des faciès autour de la ride diapirique du Jbel Azourki correspondent aux variations locales de subsidence liées aux mouvements de la couche de sel en profondeur, au taux de sédimentation et à leur rapport relatif. Ils s’inscrivent dans un contexte tectonique régional, et climatique global, qui définit l’accommodation générale et le type de remplissage sédimentaire du bassin atlasique. Le type de sédimentation, carbonatée ou mixte, joue un rôle prépondérant dans ces manifestations tectono-sédimentaires. / The evolution of the Jurassic sedimentary systems (Pliensbachian-Bajocian) in Zaouiat-Ahançal area (High Atlas, Morocco) is locally controlled by diapiric movements related to the Jbel Azourki ridge. This nearly-60-kilometer-long complex tectonic structure follows an overall WSW-ENE “bayonet-shape” outline, punctuated by six Triassic diapiric outcrops. The aim of this thesis is to characterize the role of diapirism on depositional geometries and facies distribution in three successive sedimentary systems: (1) a shallow-carbonate platform system, (2) mixed siliciclastic- and carbonate-ramp systems and (3) an oolitic-carbonate system. Therefore, a detailed geological map with the stratigraphic and facies units has been realized, as well as a set of fourteen geological sections across the Jbel Azourki diapiric ridge. The analysis of the interactions between sedimentation and diapirism has revealed a continuous recording of diapiric deformation by the entire sedimentary succession, allowing the establishment of a chronology of diapiric activity in the Zaouiat-Ahançal area. The lower-carbonate unit (1) records a polyphase deformation with the development of localized kilometer-scale basins within the platform, characterized by hemipelagic and gravity-flow deposits (rim basins). These basins are confined around the diapirs and bounded by Lithiotis-bioconstructed platform margins, which can be aggradational or erosional. From the late Pliensbachian, the mixed units (2) were affected firstly by syn-diapiric deformations at a pluri-kilometer scale, with the accumulation of several thousand-meter-thick deposits, controlled by lateral variations of the subsidence rate in and between the northern and southern flanks of the ridge, and secondly by syn-diapiric deformations at a hectometer- “diapir-edge” scale, with characteristic geometries and facies variations (oolite- and coral-rich micro platforms). The diapiric ridge reached the surface during the deposition of the mixed units and was finally capped by slightly deformed transgressive upper-carbonate unit (3) in the late Aalenian. The controlling factors on depositional geometries and facies distribution around the Jbel Azourki diapiric ridge are the local variations of the subsidence rate related to salt-movement, the sedimentation rate, and their relative ratio. They are part of the regional tectonic and global climate settings which defined the overall accommodation rate and the sedimentary filling of the atlasic basin. The type of sedimentation, carbonate- or mixed-dominated, played a major role in these tectonic-sedimentary responses.