Albian (late Early Cretaceous) pollen and spores were used to reconstruct the floral history of Allison Guyot in the Albian period, to better understand pollen and spore distributions on mid-oceanic islands, to investigate whether Allison Guyot supported land plants in the Albian, and to test previous hypotheses about the development of the guyot. Albian spores found in Allison Guyot sediments from ODP Leg 143 Site 865 include: Laevigatosporites ovatus, Cyathidites minor, Cicatricosisporites sp., Baculatisporites comaumensis, Ceratosporites equalis, Gleicheniidites senonicus, Leptolepidites verrucatus, Retitriletes circolumenus, Lycopodiacidites dettmannae, Osmundacidites wellmanii, Cicatricosisporites hughesii, Impardecispora excavate, and others. Albian pollen from these samples include Callialasporites dampieri, Ephedra, and others occur in Albian samples. The high abundance of terrestrial palynomorphs in these samples suggests that Allison Guyot was exposed in the Albian and supported land plants. The high frequency of spores (more than 90 percent) reflects a flora dominated by ferns.

Central southern Fiordland, New Zealand, is underlain extensively by metasediments and associated metavolcanics. These are mapped in three lithostratigraphic units, from west to east Edgecumbe Group, Cameron Group and Cumbrae Supergroup. Lower Cameron Group units lithocorrelate with Central Fiordland Belt lithological associations and with those of Fraser Complex, Westland. Eastern Fiordland Belt metavolcanics and lacustrine metasediments are tectonostratigraphically unrelated to Cameron Group, from which they are separated by the Grebe Fault. They instead have affiliations with the Loch Burn Formation, Largs Volcanics, Drumduan Group and Paterson Group. These units (collectively, "Cumbrae Supergroup") represent remnants of a Triassic-Jurassic calc-alkaline arc. Six deformational episodes are identified in central southern Fiordland. The earliest, D₁, is obliterated by D₂ and M₂ metamorphism. D₃ is restricted to the Southwest Fiordland Block. D₄ occupied a brief interval of M₃ time. D₄ of the Central and Western Fiordland Belts corresponds to earliest deformation in Eastern Fiordland Belt metavolcanics. The Grebe Fault is a left-lateral reverse D₄ fault; now vertical, it previously dipped eastward. The Dusky Fault, a reactivated D₅ left-lateral transfer structure, accommodated the dip-slip component of displacement at low-angle normal faults during mid-Cretaceous extension. Open folds represent D₆. Post-glacial scarps mark the post-D₆ Kilcoy and Vincent Faults. Their merged northward continuation is intersected by the tailrace tunnel of the Manapouri Hydroelectric Power Station. Southwest Fiordland Block pelites were metamorphosed at 665 �C, c. 3 kbar during M₂. Early M₃ is of contact metamorphic aspect. Late M₃ is distinctively polybaric: Central Fiordland Belt kyanite-garnet pelites recrystallised at c. 8.5 kbar after metamorphism in the sillimanite field at c. 3.5 kbar. Western Fiordland Orthogneiss 12 kbar granulite assemblages formed during late M₃. South of the Dusky Fault, late M₃ is almost asymptomatic. The M₃ field gradient is continuous across the Grebe Fault: in the Eastern Fiordland Belt, late M₃ staurolite and garnet supersede chloritoid in lacustrine (meta-)sapropel-silts. The Grebe Fault is an important tectonostratigraphic break; it may separate New Zealand�s Western and Eastern Provinces. Its relationship to any "Median Tectonic Zone" is unclear, as no such zone has been found in southeastern Fiordland. Cumbrae Supergroup rocks within the "Median Tectonic Zone" represent the arc that nourished the Eastern Province�s Barretts Formation, Murihiku Supergroup and Stephens Subgroup. The Cumbrae arc was �obducted� westwards during Early Cretaceous continent-arc collision. This event simultaneously halted Eastern Province volcanogenic sedimentation and tectonically buried Fiordland, imposing late M₃ pressure increments. Drumduan Group lawsonite is coeval. Cretaceous collision induced glaciation. Late Cretaceous climatic deterioration and extensional tectonism caused icecap development. The Otago "Peneplain" is a Late Cretaceous subglacial floor. Accumulation of voluminous perennial Cretaceous ice on Earth has hitherto not been inferred. Facultative psychrophily in New Zealand�s ancient endemics and their preference for dark conditions reflect passage through a hitherto-unsuspected evolutionary bottleneck: prolonged winter darkness and harsh climate of near-polar Late Cretaceous New Zealand exerted extraordinary evolutive pressures on ancestral forms after biotic links with Gondwana were severed. New Zealand�s ancient endemics are the evolutionary derivatives of a Late Cretaceous near-polar fauna.

Thesis (Ph. D.)--University of Chicago, Dept. of the Geophysical Sciences, June 2003. / Includes bibliographical references. Also available on the Internet.

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / O presente trabalho descreve novos espÃcimes de himenÃpteros provenientes dos calcÃrios laminados do Membro Crato (Aptiano) da FormaÃÃo Santana, Bacia do Araripe, aflorantes no municÃpio de Nova Olinda, sul do Estado do CearÃ. TambÃm sumaria as diversas ocorrÃncias de himenÃpteros fÃsseis, destacando as eocretÃceas. O estudo de dez exemplares de Hymenoptera Apocrita aqui descritos revelou a ocorrÃncia de trÃs famÃlias: Sphecidae (Cretosphex magnus Darling 1990 e C. parvus Darling 1990), Sapygidae (Cretofedtschenkia santanensis Osten 2007) e Evaniidae, esta representada por um gÃnero e espÃcie novos. Na Bacia do Araripe, a subordem Symphyta à pouco comum, e os Apocrita sÃo mais diversificados, com os Parasitica reunindo formas de Ichneumonoidea, âEphialtitidae, Proctotrupidae, âMesoserphidae e Evaniidae, e os Aculeata com espÃcies de Sphecidae (os mais abundantes), Sapygidae, Rhopalosomatidae, Scoliidae, Tiphiidae, Vespidae e possivelmente Formicidae. Ao longo de sua histÃria geolÃgica, os himenÃpteros sÃo principalmente representados por vespas. A partir do JurÃssico sÃo insetos relativamente comuns, apresentando um longo perÃodo de grande diversificaÃÃo (do NeojurÃssico ao TerciÃrio), quando surgiram mais de 80% de todas as 107 famÃlias com registro fÃssil atualmente conhecidas. A extinÃÃo que afetou os organismos de modo geral ao final do CretÃceo parece tambÃm ter afetado os himenÃpteros, que mostram o maior nÃmero de famÃlias extintas por perÃodo geolÃgico de sua histÃria. Os himenÃpteros do Membro Crato estÃo preservados por substituiÃÃo mineral, articulados, com asas abertas e pernas extendidas, mostrando maior nÃmero de espÃcimes fÃmeos do que machos, sem larvas conhecidas. à uma fauna bastante distinta das principais himenopterofaunas eocretÃceas conhecidas (Espanha, MongÃlia, AustrÃlia e SibÃria), nÃo compartilhando nenhum gÃnero, mas tendo como caracterÃstica em comum a pequena participaÃÃo dos Symphyta. A histÃria da pesquisa dos himenÃpteros cretÃceos no Brasil mostra que a maioria e os mais significativos trabalhos tÃm sido efetuados por pesquisadores estrangeiros, de modo que a maior parte dos exemplares de Hymenoptera provenientes do Membro Crato da Bacia da Araripe encontra-se atualmente fora do Brasil, tornando-se necessÃrio que os paleontÃlogos brasileiros assumam o estudo desta ordem de insetos ocorrente na FormaÃÃo Santana, efetuando pesquisas que venham a contribuir efetivamente para o melhor entendimento da himenopterofauna da Bacia do Araripe e enriquecendo os acervos brasileiros com seus fÃsseis. / This thesis describes new specimens of Hymenoptera from the laminated limestone of Crato Member (Aptian), Santana Formation, Araripe Basin that outcrops at Nova Olinda district, south of the Cearà State, Brazil. It also summarizes the occurrences of fossil Hymenoptera, mainly the Early Cretaceous fauna. The study of ten specimens of Hymenoptera Apocrita described here revealed the occurrence of three families: Sphecidae (Cretosphex magnus Darling 1990 and C. parvus Darling 1990), Sapygidae (Cretofedtschenkia santanensis Osten 2007), and Evaniidae, this latter represented by a new genus and a new species. In the Araripe Basin, suborder Symphyta is unusual, and Apocrita are more diverse, with Parasitica forms (Ichneumonoidea, âEphialtitidae, Proctotrupidae, and âMesoserphidae), and Aculeata species of Sphecidae (the most abundant), Rhopalosomatidae, Sapygidae, Scoliidae, Tiphiidae, Vespidae, and possibly Formicidae. Throughout its geological history, Hymenoptera are mainly represented by wasps. They are relatively common at Jurassic time, showing a long period of great diversification (from Late Jurassic to Tertiary), when rose more than 80% of all 107 families with fossil records. The extinction that affected the organisms at the Cretaceous end seems to have also affected Hymenoptera, which show the largest number of families extinct in its history. Hymenoptera from the Crato Member are preserved by mineral substitution, articulated, with open wings, and extended legs, showing major number of female, without known larvae. It is a distinct fauna from the main known Early Cretaceous himenopterofaunas (Spain, Australia, Mongolia and Siberia), not sharing any genre, but having in common the small participation of Symphyta. The history of Cretaceous Hymenoptera research in Brazil shows that the greatest number and the most significant papers have been accomplished by foreign researchers, so the most of Hymenoptera specimens from the Crato Member of the Araripe Basin is out of Brazil. It is therefore necessary that the Brazilian researchers take the study of this order of insects that occur in the Santana Formation, performing studies which will effectively contribute to the better understanding of the himenopterofauna of the Araripe Basin and enriching the Brazilian collections with their fossils.

En domaine de plate-forme carbonatée épicontinentale peu profonde, la production sédimentaire est étroitement liée aux variations eustatiques, au climat et à la position paleogéographique. Les périodes d’émersion constituent des phases de non-dépôt durant lesquelles l’arrêt de l’enregistrement sédimentaire peut être relayé par un enregistrement diagénétique. Les transformations associées aux discontinuités (réarrangement des porosités, modifications lithologiques, circulations tardives…) peuvent avoir un rôle déterminant sur les propriétés pétrophysiques des réservoirs carbonatés. La détection des surfaces d’émersion et des produits diagénétiques associés apparaît donc essentielle pour préciser la qualité des réservoirs, par (1) la compréhension des processus sédimento-diagénétiques aux limites de séquence, (2) la comparaison de données d’affleurement et de subsurface, et la caractérisation des géométries des réservoirs associés, (3) l’analyse de l’impact de la diagenèse associée à ces surfaces (amélioration ou détérioration des propriétés réservoir).La Formation Natih d’Oman (Albien sup. – Turonien inf.) se situe au sommet d’une épaisse série de plates-formes carbonatées peu profondes et de grande extension géographique (marge de la Néotéthys). La Formation Natih est subdivisée en quatre séquences majeures (3ème ordre) constituées d’unités transgressives tabulaires à faiblement inclinées (rampe à faciès boueux) et de prismes régressifs progradants plus inclinés (barrière bioclastique bien différenicée protégeant un domaine de lagon interne) (van Buchem et al. 2002). Ces séquences se terminent par une ou plusieurs surfaces d’émersion, pouvant être associées à des incisions (Grélaud et al. 2006). La présente étude porte sur l’analyse diagénétique de ces surfaces d’émersion par l’intégration de données de terrain (Foothills d’Adam, Jebel Akhdar) et de subsurface (carottes de forage et données de puits de champs pétroliers voisins).L’analyse diagénétique détaillée des affleurements et des données de subsurface repose sur l’étude de la chronologie relative et de la répartition spatiale des phases diagénétiques associées aux surfaces d’émersion. Elle démontre la mise en place d’une diagenèse précoce dans des conditions relativement arides qui se traduisent par l’absence de karstification et de phénomènes pédogénétiques bien développés sur la plate-forme émergée. Sous les surfaces, des circulations de fluides météoriques oxydants, alimentés par des recharges latérales, entrainent une dissolution précoce des minéralogies instables et la précipitation de ciments météoriques en domaine phréatique. Cette étude diagénétique est complétée par l’analyse des phases mésogétiques et télogénétiques qui permettent de contraindre la séquence diagénétique de la Formation Natih avec les grandes étapes de déformations tectoniques et d’enfouissement.A partir de ces résultats, les produits diagénétiques et leur impact sur l’évolution des réservoirs peuvent être caractérisés et interprétés pour chaque surface. Ils résultent d'interactions complexes entre des facteurs intrinsèques et extrinsèques comme la dynamique de l'aquifère météorique, le contexte paléogéographique et géodynamique au moment des émersions, la maturité du substrat... Ces paramètres sont effectifs au moment du dépôt et des émersions. Toutefois la préservation des produits éogénétiques peut-être fortement influencée par l'évolution au cours de l'enfouissement qui se caractérise par des phénomènes de compaction, cimentation ou dissolution. / On epeiric carbonate platforms, sediment production and stratigraphic architecture are mainly controlled by sea-level variations, climate and palaeogeographic position. During periods of subaerial exposure, carbonate production/deposition stops and the sedimentary record can then be replaced by the diagenetic record. The diagenetic transformations associated to discontinuity surfaces (rearrangement of porosity distribution, lithological alteration, late fluid circulation …) may have a significant impact on carbonate reservoir properties. The characterization of subaerial exposure surfaces and associated diagenesis is therefore essential to understand and predict reservoir quality. It requires: (1) the study of the sedimentological and diagenetic processes at the sequence boundaries, (2) the integration and comparison of outcrop and subsurface data, including respective reservoir architecture, (3) the analysis of the diagenetic overprint related to these surfaces (enhancement or deterioration of reservoir properties).The Natih Formation (Late Albian – Early Turonian) is the last of a thick succession of Cretaceous epeiric carbonate platforms. It is subdivided into four third-order sequences. In each sequence, the transgressive phase is formed by flat to slightly sloping units (muddy ramp facies) whereas the regressive phase corresponds to a higher angle prograding carbonate ramp with a well developed bioclastic margin protecting an inner lagoon (van Buchem et al. 2002). These sequences are capped by one or several subaerial exposure surfaces, sometimes associated with incisions (Grélaud et al. 2006). The present study focuses on the diagenetic analysis of these emersion surfaces by the integration of outcrop (Adam Foothills, Jabal Akhdar) and subsurface data (neighbouring oil fields from the interior Oman).The detailed study of the lateral distribution and chronology of the diagenetic phases associated with emersion surfaces form the basis for the sedimentological and diagenetic model. The results highlight the development of a meteoric diagenetic system which was probably subject to relatively arid conditions, explaining the absence of karstification and pedogenetic features on the exposed platform. Below the emersion surfaces, the circulation of oxidizing meteoric fluids, laterally sourced, leads to the early dissolution of unstable minerals and the precipitation of meteoric cements in the phreatic domain.This diagenetic study is completed by the analysis of the mesogenetic and telogenetic phases, which allow to constrain the diagenetic sequence in relation with the main phases of deformation and burial of the Natih Formation.These results show the particularities of each subaerial exposure event in terms of diagenetic products and their impact on reservoir properties. They result from complex interrelations between external and intrinsic factors, such as the dynamics of meteoric aquifers, the geodynamic and paleogeographic context during exposure, chemical reactivity ... These are effective during deposition and subaerial exposure. However, the preservation of exposure-related diagenetic features may subsequently be influenced by burial evolution trough competition between compaction, cementation and dissolution.

The Cretaceous–Paleogene (K/Pg) boundary marks one of the major crises in the history of life on Earth. The cause is widely regarded as a large bolide impact at Chicxulub, Mexico, coincident with a major series of volcanic eruptions on the Deccan Plateau, India. Fieldwork in the Brazos River area of Texas has involved an investigation of the sections on the Brazos River and its tributaries. A previously overlooked K/Pg section (RBS) on the Brazos River was found and contains the most accessible and complete K/Pg boundary succession in the area. The RBS succession provides a clear exposure of the various lithological units within the Paleocene and was used to correlate to the successions in the nearby creeks. The K/Pg boundary is also well-exposed and records an erosional relief of ~1 m, cut into the Maastrichtian mudstone succession, creating a mounded topography. The overlying ‘Event Bed’, containing reworked impact spherules at its base, is shown to infill troughs on this irregular surface. The same features were recorded in tributary creeks, with all previous descriptions of these locations clearly failing to recognise the various sedimentary relationships. Distinct, thin, yellow clay horizons within the uppermost Maastrichtian mudstones are present in some sections. Geochemical analysis and radiometric dating have confirmed these as volcanic ashes, with extracted zircons giving a date of 65.95+0.04 Ma. These ash bands are located in Maastrichtian mudstones just below the K/Pg boundary and the recorded date is, within error, that of the K/Pg boundary. This identification of this latest Maastrichtian volcanic ash negates the suggestion of a pre-K/Pg boundary impact, a pre-extinction impact or multiple impacts. The benthic foraminiferal data generated indicates significant changes in palaeoecology of the benthic foraminifera across the K/Pg boundary. The benthic foraminifera do not experience a mass extinction, unlike the planktic foraminifera, which were significantly affected by the end-Maastrichtian extinction event. The benthic foraminferal assemblage appears to only experience transient, short-lived changes with pulses of agglutinated, elongate and large species in the early Paleocene. Mono-specific samples of Lenticulina rotulata have been analysed for stable isotopes and the data may indicate the presence cyclicity across the K/Pg boundary interval. In the earliest Paleocene significant negative δ18O excursions near the Pα/P1a and NP1/NP2 boundary represents a potential hyperthermal event that may be coeval with the DAN-C2 and Lower C29n events respectively recorded at Gubbio, and in the Atlantic Ocean. A sequence stratigraphy package is determined based on the micropaleontology and sedimentology in the Brazos River area. The latest Maastrichtian is marked by a sealevel rise immediately before the K/Pg boundary. Immediately after the K/Pg event, sealevel fell and is recorded as a change from mid to inner shelf. The condensed unit of the Middle Sandstone Bed (MSB) represents a Transgressive systems tract, with increasing diversity and abundance of benthic foraminifera to the top of the MSB, where maximum abundance and diversity is marks a Maximum Flooding Surface. The interval above indicates sea-level continuing to rise to a mid to outer-shelf setting. These sealevel changes are also recorded at the same stratigraphic level in Alabama, and at more distal K/Pg boundary sections (e.g., Denmark and Tunisia) suggesting that these sealevel changes are eustatically controlled.

>Magister Scientiae - MSc / Clay diagenesis phenomenon and their effects on some petrophysical properties of lower cretaceous silliciclastic sandstones, offshore Orange basin have been established. Previous studies on Orange basin revealed that chlorite and quartz cements have significantly compromised the reservoir quality in this basin but it is expected that the reservoirs shows better improvement basinward, an analogy of this is displayed by tertiary sandstones deposit, offshore Angola. The main goal of this thesis is to perform reservoir quality evaluation by intergrating geological, geochemical and geophysical tools to substantiate the effects of clay minerals distribution and its subsequent diagenesis on the intrinsic properties (porosity, permeability and saturation) of reservoir intervals encountered within three wells in block 3A (deeper waters), offshore Orange basin. Five lithofacies were identified based on detailed core description from wells KF-1, KH-1 and AU-1 in this block. The facies were grouped based on colour and grain sizes, they are named : A1 (shale), A2 (sandstone), A3 (siltstone), A4 (dark coloured sandstone) and A5 (conglomerates).Depositional environment is predominantly marine, specifically, marine delta front detached bars and deepwater turbiditic sandstone deposit. Geophysical wire line logs of gamma ray, resistivity logs combo and porosity logs were interpreted, parameters and properties such as VCL, porosity, permeability and saturation were estimated from these logs and the values obtained were compared with values from conventional core analysis data, the values agreed well with each other. Detailed petrographic studies (SEM, XRD and thinsection) plus geochemical studies (CEC, EDS, pH, Ec) were carried out on twenty two core samples to establish if these clay minerals and other cements have pervasive effects on the reservoir quality or otherwise.

The Upper Cretaceous (Campanian) Cedar District Formation of the Gulf Islands and adjacent areas is composed of shale and sandstone, which are present as thick sequences of shale, which may or may not be fossiliferous, and as alternating rhythmic sandstone-shale sequences of the flysch-type. Presence of graded bedding, ripple and convolute laminations, and sole marks in the latter suggest a turbidity current origin. The internal structures of the individual turbidite units correspond largely to the C-E divisions of Bouma (1962) and other authors, and indicate that their deposition took place largely within the lower flow regime. Convolute lamination in the sandstones was formed by oversteepening and deformation of pre-existing ripple lamination and by the deformation of pre-existing plane-parallel lamination by the drag of the overpassing currents. Flute and groove casts and frondescent marks were only found in beds thicker than a foot and a half. Calcareous concretions, most abundant in the shales and occasionally phosphatic, are crossed by organic borings and burrows which are filled with sediments of the surrounding beds. Host rocks of the calcareous concretions tend to thicken around them. The concretions show deformation when present in beds involved in soft-sediment deformation. All these observations suggest their formation in the early stage of diagenesis, probably shortly after, burial. Sandstones of the Cedar District Formation show a gradation from arenites that lack matrix and have a cal-cite cement, to wackes rich in fine-grained matrix. The majority of the wackes and the arenites are feldspathic and arkosic, using the classification of Gilbert (1954). Their composition indicates that the major source was acidic to intermediate igneous and/or low to medium grade metamorphic rock , sedimentary and volcanic rocks were a secondary source. The major source area was possibly a region of high relief that had undergone rapid uplift and erosion, and experienced mainly mechanical weathering. Paleocurrents and lithologic lateral variation indicate that the major source area for the coarse elastics was situated to the east and southeast of the study area. The pre-Jurassic low grade metamorphic rocks of the Cascade Mountains to the east, and the pre-Carboniferous- crystalline rocks of the San Juan Islands to the southeast served as possible source areas for the coarse elastics. Deposition of shaley, fossilif erous parts, of the formation in the southeastern part, of the study area, took place in littoral to upper neritic depths. Turbidite (flysch-type) sequences were deposited in deeper water, below the wave base. The unfossiliferous shale of the central and northern parts of the study area was deposited either at about the same depths as the turbidites, or in deeper water, since thin, delicate, horizontal and-cross laminations are preserved in these rocks. Paleontologic evidence suggests that deposition took place in a somewhat restricted basin having a narrow connection with the open ocean to the west. Paleontologic and mineralogic data suggest that the bottom conditions of the central and northern parts of the basin of deposition were stagnant and reducing. Facies relationships suggest that the basin of deposition had its longest dimension trending SE-NW. Its eastern, southeastern, and southern boundaries were situated between the mainland of British Columbia-Washington and the Gulf-San Juan Islands. Its northern and northwestern boundaries were possibly near the city of Nanaimo and Gabriola Island. To the west, it was connected at least partially to the open ocean. In the southeastern part of the study area, alternation of thick, fossiliferous shale sequences, and sequences which are predominantly turbidites suggests fluctuations in the depth of the basin floor, either due to changes in sea level or to tectonic movements. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate

L’étude menée dans cette thèse, révise les faunes continentales du Crétacé supérieur (Campanien, Maastrichtien) de Provence (Bouches-du-Rhône et Var). Les recherches ont été menées sur plusieurs points : établir un inventaire précis des gisements paléontologiques, établir une liste faunique exhaustive pour chaque gisement, corréler les différents sites dans la stratigraphie générale et étudier les caractéristiques de la faune provençale. L’inventaire des sites fossilifères provençaux tient compte de plus d’une dizaine de nouveaux sites.Le recensement faunique de ces sites révèle des compositions semblables, à hauts niveaux de rangs taxinomiques. Dans le détail, elle comporte de légères variations selon l’âge des gisements, la localisation géographique et le contexte environnemental. L’actualisation des données met en évidence une richesse taxinomique bien plus importante que précédemment estimée. Le repositionnement stratigraphique des sites provençaux dans le Crétacé supérieur a été effectué à l’aide de marqueurs biostratigraphiques classiques et de l’oostratigraphie, permettant ainsi de corriger l’âge de certains sites historiques.L’examen de la paléobiodiversité provençale a tenu compte de la variabilité (intra ou interspécifique) et de la définition de nouveaux taxons. La variabilité/diversité de certains (titanosaures, Rhabdodon, théropodes ; nodosauridés) a été estimée grâce à l’utilisation de morphotypes.En caractérisant la faune provençale, ce travail pose les bases de l’étude de la faune à l’échelle de l’île ibéro-armoricaine. A l’échelle provençale, cette faune présente des caractéristiques d’une évolution en milieu insulaire avec quelques spécificités. / The study led within the framework of this thesis, reports on the Upper Cretaceous continental faunae (Campanian, Maastrichtian) of Provence (Boûches-du-Rhone and Var).Researches were focused on several aspects: Establish a precise inventory of the known paleontological deposits; establish a faunal exhaustive list for each deposit, correlate the various sites in the general stratigraphy and study the characteristics of Provencal fauna. Provencal fossil inventory takes into account more than about ten new localities.The fauna inventory of all these sites reveals similar compositions at high taxonomic levels. However, in detail, this fauna contains light variations according to the age of the localities, the geographical location and the environmental context. Data updating highlights a taxonomic richness more important than previously estimated. The stratigraphic reposition of the various localities from Provence in the Upper Cretaceous was carried out by the use of classic biostratigraphic markers and oostratigraphy, which allowed correcting the age of some historical sites.The study of paleobiodiversity in Provence took into account the variability (intra or interspecific) and the definition of new taxa. The variability/diversity of some taxa (titanosaurs, Rhabdodon, theropods, nodosaurids) was estimated thanks to the use of precise morphotypes.By characterizing the fauna from Provence, this work establishes the bases of the study of the Fauna on ibero-Armorican island (which includes Provence). At the Provence scale, this fauna presents many characteristics of an evolution in island environment with some evolutionary specificities.

Despite the economic importance of dolomitised Upper Cretaceous strata, little work has been conducted to further the understanding of the controls on dolomitisation during a green-house period with low marine Mg/Ca ratio. This study presents a multidisciplinary, multi-scale approach using field, petrographical and geochemical data to understand the mechanism of dolomitisation in North Africa and western Mediterranean in order to determine the controls on dolomitisation of Upper Cretaceous strata. Two field areas have been chosen that exhibit similar facies and are time equivalent, located along the Jeffara Escarpment in southern Tunisia and in the Iberian Range of central Spain. Both areas comprise facies deposited in mid-ramp, platform margin, lagoon, inter- and supra-tidal environments. Based on the distribution of facies, a sequence stratigraphic model was proposed for both areas which show similar changes in relative sea level. In the Iberian Basin there is strong evidence of a dramatic rearrangement in basin architecture resulting from tectonic activity during the Upper Cenomanian, whilst on the Jeffara Escarpment deposition took place on a passive margin. Both areas show evidence of warm, arid climates; even though the Iberian Range was in a more northerly palaeogeographic position, there was a rain shadow which affected facies distribution and dolomitisation. Planar dolomite fabrics, dull luminescence under cathodoluminescence, marine trace element concentrations and marine to slightly enriched oxygen isotope values suggest that dolomitisation occurred from mesosaline, marine fluids. Dolomitisation occurred from multiple fluxes of dolomitising fluids, controlled by high frequency changes in relative sea level. A cessation of dolomitisation only occurred during late transgressive systems tract of low order sea level cycles as a result of platform flooding. The Distribution of dolomitising fluids was partly controlled by pre-cursor limestone with low permeability horizons acting as aquicludes and permeable sandstones acting as aquifers. Changes in basin architecture caused reversals in flow of dolomitising fluids on the Iberian Range whilst increased subsidence caused cessation of dolomitisation due to rapid increase in relative sea level on the platform top. Dolomitisation occurred over a wider geographical area in the Jeffara Escarpment compared to the Iberian Range as a result of higher fluid salinity, larger brine pool and higher temperature of dolomitising fluids. The distribution of dolomitised strata of the circum-Tethys and across the Arabian Plate suggests that early reflux dolomitisation occurred within arid climate belts, and did not require hypersaline conditions, evidenced by evaporite distribution, as previously suggested. This study has important implications for the hydrocarbon industry by improving our ability to predict distribution, size and geometry of dolomitised strata essential for hydrocarbon exploration and field development. Furthermore this study has improved our understanding on the controls on dolomitisation during greenhouse periods with low Mg/Ca ratio of seawater and high frequency sea level changes.