Dissertations / Theses on the topic 'Rudistes'

Los bivalvos rudistas están ampliamente representados entre las sucesiones de materiales carbonatados someros correspondientes al margen sur de la cuenca pirenaica durante el Cretácico superior y que hoy día afloran a lo largo del Pirineo meridional-central. Las faunas del Coniaciense superior/Santoniense inferior al Maastrichtiense son bastante bien conocidas y han sido objeto de diferentes estudios, pero no es así para las anteriores que, si se conocen, es principalmente por citas en algunos trabajos. El estudio de diferentes afloramientos correspondientes al Cenomaniense, Turoniense superior y Coniaciense, alrededor de la cuenca de Tremp (zona de Sopeira y la Sierra de Sant Gervàs, Congost d’Erinyà, Hortoneda, anticlinal de Bóixols-Abella-Sant Corneli y sinclinal de Santa Fe, y Sierra del Montsec), ha proporcionado una abundante fauna de rudistas a partir de la cual se ha podido realizar un exhaustivo estudio paleontológico que comprende descripciones detalladas y actualizadas de los diferentes taxones representados, análisis de la variabilidad intraespecífica y distribución bioestratigráfica. En total se han reconocido 35 especies correspondientes a 15 géneros de 7 familias distintas. La fauna de rudistas del Cenomaniense medio-superior está representada por Caprina adversa, Ichthyosarcolites triangularis, I. monocarinatus, I. tricarinatus, Durania blayaci, Eoradiolites sp., Sauvagesia tellensis y Sphaerulites foliaceus. Caprina adversa también se registra desde el Cenomaniense inferior. El Turoniense superior contiene una fauna formada por Hippurites resectus, Pseudovaccinites inferus, P. petrocoriensis, P. praegiganteus, P. rousseli, Praeradiolites paillettei y Sphaerulites patera. Algunas especies bien representadas en el Coniaciense se registran de forma puntual en algún afloramiento atribuido al Turoniense superior, entre ellas Biradiolites canaliculatus, Hippurites incisus, Pseudovaccinites zurcheri o P. corbaricus?. De la misma forma, Pseudovaccinites petrocoriensis y P. corbaricus? aún se reconocen en el Coniaciense inferior. El Coniaciense inferior, medio y superior se distingue en diferentes localidades. Se reconocen Bayleia sp., Hippurites incisus, H. socialis, Hippuritella sp. 1, Hippuritella sp. 2, P. corbaricus?, Pseudovaccinites giganteus, P. marticensis, P. petrocoriensis, P. zurcheri, Gyropleura? sp. 1, Gyropleura? sp. 2, Plagioptychus aguilloni, Plagioptychus cf. toucasi, Radiolites praegalloprovincialis, Radiolites sp. 1, Radiolites sp. 2, Biradiolites canaliculatus, Biradiolites cf. beaussetensis, Praeradiolites paillettei, Praeradiolites requieni y Sphaerulites sp. Algunas especies están representadas durante la mayor parte del Coniaciense, mientras que otras solamente de forma local. El momento de mayor diversidad taxonómica se produce en el Coniaciense superior, cuando se registran conjuntamente la mayoría de especies de esa edad.
Rudist bivalves are widely represented among the successions of shallow carbonate materials corresponding to the southern margin of the Pyrenean basin during the Late Cretaceous and that emerge today along the South-central Pyrenees. The upper Coniacian/lower Santonian to Maastrichtian faunas are well known and have been the subject of several studies but it is not the case for the older ones, mainly known through appointments in some works. The study of different outcrops of the Cenomanian, upper Turonian, and Coniacian around the Tremp basin (Sopeira area and the Sierra de Sant Gervàs, Congost d'Erinyà, Hortoneda, Bóixols-Abella-Sant Corneli anticline and Santa Fe syncline, and Sierra del Montsec), has provided an abundant rudists fauna on which it has been possible to perform an exhaustive paleontological study, comprising detailed and updated descriptions of the various taxa represented as well as an analysis of both their intraspecific variability and biostratigraphical distribution. In total, 35 species corresponding to 15 genera of 7 different families have been recognized. The middle-upper Cenomanian rudists fauna is represented by Caprina adversa, Ichthyosarcolites triangularis, I. monocarinatus, I. tricarinatus, Durania blayaci, Eoradiolites sp., Sauvagesia tellensis and Sphaerulites foliaceus. Caprina adversa also is recorded from the lower Cenomanian. The upper Turonian contains a rudists fauna composed of Hippurites resectus, Pseudovaccinites inferus, P. petrocoriensis, P. praegiganteus, P. rousseli, Praeradiolites paillettei and Sphaerulites patera. Species well represented in the Coniacian as Biradiolites canaliculatus, Hippurites incisus, Pseudovaccinites zurcheri or P. corbaricus?, are recorded sporadically in some outcrops attributed to the upper Turonian. At the same time, Pseudovaccinites petrocoriensis and P. corbaricus? are still recorded in the lower Coniacian. The lower, middle and upper Coniacian is identified in different locations. The following rudist taxa are recognized: Bayleia sp., Hippurites incisus, H. socialis, Hippuritella sp. 1, Hippuritella sp. 2, P. corbaricus?, Pseudovaccinites giganteus, P. marticensis, P. petrocoriensis, P. zurcheri, Gyropleura? sp. 1, Gyropleura? sp. 2, Plagioptychus aguilloni, Plagioptychus cf. toucasi, Radiolites praegalloprovincialis, Radiolites sp. 1, Radiolites sp. 2, Biradiolites canaliculatus, Biradiolites cf. beaussetensis, Praeradiolites paillettei, Praeradiolites requieni and Sphaerulites sp. Some species are represented during most of the Coniacian, while other only locally. The time of greatest taxonomic diversity occurs in the upper Coniacian, when most of that age species are recorded together.

La revision de l'ensemble des caprinidae du cretace inferieur, met en evidence 48 especes reparties dans 17 genres appartenant aux deux sous-familles des caprininae et des coalcomaninae. Huit especes ont ete invalidees. Deux nouveaux genres, pacificaprina et pseudocaprina, ainsi que quatre nouvelles especes, sont proposes, trois taxons etant laisses en nomenclature ouverte. La famille et les sous-familles sont definies d'apres l'appareil myophoral et non pas sur la presence ou non de canaux. Cette nouvelle acception de la famille et des deux sous-familles repose essentiellement sur le developpement du myophore posterieur dans l'une ou l'autre valve et sur la position des insertions musculaires correspondantes. Les criteres diagnostiques specifiques et generiques sont bases sur la disposition et l'architecture des canaux. Ainsi la sous-famille des caprininae est caracterisee par un developpement d'une lame myophorale posterieure sur la valve inferieure et surtout par la position externe de l'insertion musculaire sur cette lame alors qu'elle est interne sur celle de la valve superieure. La sous-famille des coalcomaninae est caracterisee par le developpement d'une lame myophorale posterieure sur la valve superieure et surtout par la position externe de l'insertion musculaire sur cette lame alors qu'elle est interne sur celle de la valve inferieure. La typologie des canaux completee par une analyse geometrique et architecturale est replacee dans un cadre evolutif qu'elle contribue a definir. L'evolution morphologique de la geometrie des canaux, l'augmentation de la complexite de l'architecture par l'apparition de planchers ou de cloisons transverses, et le developpement progressif des canaux sur l'une et l'autre valve et sur leur pourtour, ont servi de base a l'etude cladistique et evolutive. Les caprinidae occupent un milieu relativement etroit dans le domaine externe des plates-formes carbonatees, ils apparaissent a l'hauterivien et disparaissent a la fin du cenomanien. Les diversites generique et specifique sont les plus fortes a l'aptien inferieur pour les caprininae et a l'albien pour les coalcomaninae. Les deux sous-familles subissent la crise medio-aptienne. Du point de vue de la repartition paleobiogeographique des caprinidae, les coalcomaninae ont une distribution exclusivement americaine et ouest-pacifique, alors que les caprininae ont une repartition cosmopolite bien que la pluspart des especes se cantonnent au domaine mediterraneen.

Ce travail repose sur l'etude de plusieurs populations d'hippuritidae, d'age turonien a campanien, provenant du sud-est de la france, des pyrenees et du sultanat d'oman. Pres de mille specimens ont ete soumis a une analyse biometrique, les mieux conserves ont permis l'etude de l'ontogenese. Le traitement statistique des donnees permet, sur des bases objectives et en tenant compte d'une forte variabilite intraspecifique, de preciser les limites de chaque espece et de proposer des revisions systematiques. L'etude des principales especes de vaccinites de provence et des pyrenees aboutit a une simplification de la systematique. Il a ete reconnu une espece ancestrale unique, vaccinites inferus, dont derivent au turonien superieur trois lignees phyletiques assimilables a des chrono-especes. Dans chacune d'elle trois especes paleontologiques (ou transiants) ont pu etre distinguees, leur evolution se realise par anagenese. Vaccinites inferus etait repandu dans tout le domaine mediterraneen, mais a partir du coniacien les especes qui lui succedent etaient confinees a la province occidentale. L'etude des vaccinites d'oman permet de reconstituer la lignee du vaccinites inaequicostatus. Cette lignee de la province orientale rassemble trois especes et parait avoir une origine commune avec les vaccinites du domaine americano-caraibe. Les comparaisons effectuees entre les plus anciennes formes d'hippuritidae mettent en evidence un important polymorphisme ecologique s'exprimant principalement sur le mode de croissance des individus. Cela permet d'envisager l'existence, au debut du turonien, d'une espece primitive unique a l'origine de tous les hippuritidae. L'etude de l'ontogenese montre que l'evolution phyletique peut etre interpretee par l'action d'heterochronies du developpement, principalement l'acceleration et la neotenie. Une classification basee sur les caracteres internes est proposee ; deux morphogenres sont distingues : hippurites et vaccinites.

Les rudistes bivalves forment un groupe monophylétique qui s’étend dans le registre fossile de 160 à 66 millions d’années. L’objectif de cette thèse est de porter un nouveau regard sur l’histoire évolutionnaire de ce groupe dans le cadre de la théorie cladistique. Dans une première partie sont posées les bases théoriques, méthodologiques et techniques de l’analyse à trois éléments. Le concept de triplet permet de proposer des arguments sur la pertinence des arbres consensus. La méthode d’analyse à trois éléments est ensuite comparée à la méthode de parcimonie grâce à des arguments théoriques et méthodologiques, ainsi que par des simulations basées sur des modèles d’évolution. Dans une seconde partie, nous appliquons la théorie et la méthode à la reconstruction de l’histoire des rudistes. Le genre Ichthyosarcolites est révisé, et des analyses statistiques permettent de tester la pertinence des hypothèses d’homologie basée sur la forme de la coquille. Les hypothèses d’homologie sont revues et de nouveaux caractères basés sur les myophores et les canaux palléaux sont formalisés pour l’ensemble des Hippuritida. La nouvelle phylogénie qui en découle est cohérente avec l’âge géologique et permet de raffiner l’histoire évolutive des rudistes au Crétacé. L’étude de couches Cénomaniennes du Bassin Sud-Provençal (Var, France) nous permettent de faire un lien entre l’histoire de la diversification des rudistes et leur paléoécologie
The rudist bivalves form a monophyletic group that extends in the fossil record from 160 to 66 million years. The objective of this thesis is to propose new insights at the evolutionary history of this group within the framework of cladistic theory. In the first part, we lay the theoretical, methodological and technical foundations of the three-item analysis. The concept of triplet allows us to propose arguments on the relevance of consensus trees in cladistics. The three-item analysis method is then compared to the method of parsimony using theoretical and methodological arguments, and simulations based on evolutionary models. In a second part, we apply the theory and method to the reconstruction of the rudist history. The genus Ichthyosarcolites is reviewed, and statistical analyses are used to test the relevance of homology hypotheses based on shell shape. Hypotheses of homology and new characters based on myophores and pallial canals are tested on the Hippuritida. The new, resulting phylogeny is consistent with known geological occurrences of the group and further our understanding of rudist evolutionary history during the Cretaceous. The study of Cenomanian outcrops of the South Provence Basin (Var, France) allows us to make a link between the history of the diversification of rudists and their paleoecology

Les formations carbonatees a rudistes du cretace superieur de l'argolide septentrionale se trouvent dans une region tectoniquement complexe, celle du massif de l'akros. Le massif de l'akros est forme par l'affrontement tectonique de deux empilements d'ecailles. L'un (portant une semelle de serpentinite ecrasee), charrie sur le flysch post-pyresien de la zone de trapezona appartient a la zone pelagonienne. Il est compose de trois ecailles superposees, soit de bas en haut: l'autochtone relatif d'age cenomanien a turonien, l'ecaille intermediaire d'age turonien et l'ecaille superieure d'age santonien superieur a campanien. L'autre, present seulement dans le flanc sud de l'akros appartient a la zone de trapezona. Il comprend cinq ecailles superposees, soit de bas en haut: l'ecaille de lalioteika d'age maastrichtien moyen a sup. ; l'ecaille de tsoleika d'age cenomanien a campanien avec un hiatus stratigraphique du turonien au santonien, l'ecaille du pli couche d'age cenomanien moyen a superieur, l'ecaille du relais d'age maastrichtien superieur et l'ecaille sommitale de l'akros d'age maastrichtien inferieur a moyen. Dans le secteur de ligourion, trois series inverses ont pu etre observees. Dans les deux zones, le turonien apparait comme une periode marquee par des bouleversements paleogeographiques de grande ampleur. (niveaux condenses, hard-grounds detritisme). Un isolement paleogeographique a conduit au developpement d'un endemisme: a orbitolines et plypiers au cretace inferieur (zone de trapezona) et a rudistes et ostracodes au cretace superieur (zone pelagonienne)

Les rudistes bivalves forment un groupe monophylétique qui s’étend dans le registre fossile de 160 à 66 millions d’années. L’objectif de cette thèse est de porter un nouveau regard sur l’histoire évolutionnaire de ce groupe dans le cadre de la théorie cladistique. Dans une première partie sont posées les bases théoriques, méthodologiques et techniques de l’analyse à trois éléments. Le concept de triplet permet de proposer des arguments sur la pertinence des arbres consensus. La méthode d’analyse à trois éléments est ensuite comparée à la méthode de parcimonie grâce à des arguments théoriques et méthodologiques, ainsi que par des simulations basées sur des modèles d’évolution. Dans une seconde partie, nous appliquons la théorie et la méthode à la reconstruction de l’histoire des rudistes. Le genre Ichthyosarcolites est révisé, et des analyses statistiques permettent de tester la pertinence des hypothèses d’homologie basée sur la forme de la coquille. Les hypothèses d’homologie sont revues et de nouveaux caractères basés sur les myophores et les canaux palléaux sont formalisés pour l’ensemble des Hippuritida. La nouvelle phylogénie qui en découle est cohérente avec l’âge géologique et permet de raffiner l’histoire évolutive des rudistes au Crétacé. L’étude de couches Cénomaniennes du Bassin Sud-Provençal (Var, France) nous permettent de faire un lien entre l’histoire de la diversification des rudistes et leur paléoécologie
The rudist bivalves form a monophyletic group that extends in the fossil record from 160 to 66 million years. The objective of this thesis is to propose new insights at the evolutionary history of this group within the framework of cladistic theory. In the first part, we lay the theoretical, methodological and technical foundations of the three-item analysis. The concept of triplet allows us to propose arguments on the relevance of consensus trees in cladistics. The three-item analysis method is then compared to the method of parsimony using theoretical and methodological arguments, and simulations based on evolutionary models. In a second part, we apply the theory and method to the reconstruction of the rudist history. The genus Ichthyosarcolites is reviewed, and statistical analyses are used to test the relevance of homology hypotheses based on shell shape. Hypotheses of homology and new characters based on myophores and pallial canals are tested on the Hippuritida. The new, resulting phylogeny is consistent with known geological occurrences of the group and further our understanding of rudist evolutionary history during the Cretaceous. The study of Cenomanian outcrops of the South Provence Basin (Var, France) allows us to make a link between the history of the diversification of rudists and their paleoecology

Les plates-formes carbonatées du Crétacé inférieur de la marge ouest-européenne de la Téthys (SE de la France et de l'Espagne) montrent quarante trois communautés à rudistes, définies par l'analyse ACP de onze caractères biologiques et sédimentologiques, et des taxons index. Il existe six types principaux de communautés plus ou moins pérennes au cours du temps. Leur dynamique identifie trois phases bionomiques successives encadrées par des évènements d'extinctions ; ce sont les groupements distaux qui enregistrent les plus forts taux de renouvellements taxonomiques. Ces changements résultent de modifications environnementales et biologiques (évolution). La proportion de carbonate accumulée par les rudistes, dans les sédiments, varie de 14 % (milieux proximaux) à 21 % (milieux distaux). Le potentiel bioconstructeur oscille de manière plus ou moins périodique et s'élève à l'Aptien supérieur-Albien, suite au développement des morphotypes " élévateurs " , i. E. Les Radiolitidae

L’intérêt scientifique porté depuis plusieurs décennies au développement des plateformes carbonatées tropicales s’explique par la complexité des facteurs de contrôle de la sédimentation, qui montre une influence de la tectonique, du climat, de l’eustatisme, de l’hydrodynamisme etc… Les plateformes carbonatées ne sont pas seulement des environnements enclins à accumuler des sédiments, mais sont aussi de prolifiques « usines » à carbonates qui produisent davantage que ce qu’elles peuvent stocker. Les sédiments en excès sont transférés vers le bassin profond. Ainsi, les transitions plateforme – bassin illustrent les interactions entre production carbonatée in-situ, transfert, et accumulation sédimentaire issue de la re-sédimentation. Dans le sud-ouest de l’Albanie, la série carbonatée du Crétacé Supérieur est composée de dépôts sédimentaire de plateforme et de bassin. Ces successions sont à présent intégrées dans le système chevauchant de la chaîne Dinarides - Hellénides, dont la mise en place est contemporaine d’une phase de déformation orogénique Plio-Holocène. La paléogéographie de la région péri-Adriatique au Crétacé Supérieur révèle une juxtaposition de méga-plateformes et de bassins adjacents dont le remplissage est en partie conditionné par la remobilisation gravitaire des sédiments de la bordure de plateforme. Les investigations sont menées sur cinq zones d’étude. Elles intègrent des descriptions faciologiques macro- et microscopiques pour chacune des huit successions étudiées. Les unités définies font l’objet d’une cartographie à l’échelle de la zone d’étude qui précise l’architecture stratigraphique du système. La datation des dépôts repose sur une étude biostratigraphique, elle est renforcée par les données chronostratigraphiques des isotopes du strontium. Sur la plateforme, les descriptions faciologiques sont appuyées par des méthodes complémentaires de pétrographie (cathodoluminescence, épifluorescence, microscopie électronique à balayage), de pétrophysique (porosimétrie à injection mercure) et de géochimie (isotopes stables du carbone et de l’oxygène) visant à révéler la dynamique de sédimentation et les propriétés réservoir de la succession.Les conditions de sédimentation sont précisées, i) sur la plateforme, dix faciès spécifiques sont identifiés, représentatifs de contidions de dépôt supra-, inter-, et subtidales. Ils s’intègrent dans des motifs d’empilement distinctifs (small-scale sequences) qui attestent le caractère cyclique de la sédimentation, contrôlé par des fluctuations haute-fréquence et basse amplitude du niveau marin relatif; ii) dans le bassin, quatorze faciès sont classés suivant le mécanisme de transport sédimentaire dominant. La répartition spatiale des dépôts permet d’identifier la provenance et les sources préférentielles du matériel calci-clastique. L’évolution tectono-sédimentaire plateforme – bassin au Crétacé Supérieur est déterminée par deux séquences: i) du Cénomanien au Turonien, la sédimentation de plateforme est caractérisée par l’aggradation plus de 700 mètres de faciès intertidaux organisés en séquences (small-scale sequences) émersives ou sub-émersives. Aucun transfert significatif n’est attesté dans le bassin adjacent, témoignant d’une relative stabilité du système évoluant dans un contexte subsident ; ii) l’intervalle Coniacien – Santonien marque l’installation d’une plateforme à rudistes favorable au transfert sédimentaire. Ce dernier se traduit par une progradation marquée des dépôts gravitaires dans le bassin pendant le Campanien. Cette dynamique de transfert est accentuée par la mise en place de slumps résultants du démantèlement tectonique de la bordure de plateforme au Campanien Supérieur et Maastrichtien
The evolution of tropical carbonate platforms depends on complex interacting factors influencing the sedimentation, such as tectonism, climate, eustacy, hydrodynamism etc… Due to this complexity, it has been of scientific interest for decades. Carbonate platforms are not only prone to accumulate sediments, but also represent prolific carbonates “factories” producing more than they can store on their tops. Excess sediments are shed basinward. Platform-to-basin transitions exemplify interactions between in-situ carbonate production, transfer and sedimentary accumulations resulting from re-sedimentation. In south-west Albania, the Upper Cretaceous carbonate series are made up of platform and basinal deposits. Sedimentary successions are presently integrated in the Dinarides-Hellenides fold-and thrust belt that originate from a Plio-Holocene phase of the Alpine Orogeny. The paleogeographic setting during the Late Cretaceous reveals a juxtaposition of mega-platforms and adjacent basins, partly filled with sediments derived from the shelf edge. Our scientific investigations focused on five study areas. Macro- and microfacies descriptions are provided for eight platform and basin successions. Sedimentary units are defined and mapped on each study area, supporting the stratigraphic reconstruction of the system. Dating is based on biostratigraphy and supported by strontium-isotope data. Regarding platform deposits, facies descriptions are seconded by complementary methods of petrography (cathodoluminescence, epifluorescence, scanning electron microscopy), petrophysics (mercury intrusion porosimetry), and geochemistry (stable carbon and oxygen isotopes), aiming to precise the sedimentation dynamics and reservoir properties of the succession. The sedimentation conditions are specified: i) within the platform, ten specific facies are identified, precising the depositional setting that comprise supra-, inter- and subtidal environments. These facies are integrated in distinctive stacking patterns (small-scale-sequences) pointing to a cyclic sedimentary dynamic controlled by high-frequency and low-amplitude sea level changes; ii) the basinal deposits comprise fourteen facies classified according to the dominant grain-support mechanism. Spatial distribution of the deposits allowed identifying the provenance and preferential sources of calciclatic sediments. The tectono-sedimentary evolution of the platform-to-basin system during the Late Cretaceous can be subdivided into two sequences: i) from the Cenomanian to the Turonian, the platform sedimentation is characterized by a substantial aggradation (700 meters) of intertidal small-scale sequences. No significant transfer was evidenced in the adjacent Ionian Basin, pointing to stable conditions in a subsiding context; ii) the Coniacian-Santonian interval evidences the establishment of a rudist platform massively shedding sediments basinward during the Campanian. A clear progradation of gravity-flow deposits is attested during this period. During the Upper Campanian and Maastrichtian, this transfer is accentuated by the setting of tectonically-triggered slumps resulting from the dismantling of the platform edge

Ce memoire traite de la biosedimentologie de la formation de la cadiere, var. Cette formation peut etre subdivisee en cinq unites lithostratigraphiques constituees principalement de couches de calcaire a rudistes. Toutefois, on observe des variations laterales des facies dont les relations sont precisees et synthetisees grace a une analyse sequentielle. On montre que les sequences elementaires s'inscrivent dans une sequence de comblement. L'analyse des microfacies sur le plan sedimentologique et paleoecologique permet d'envisager la reconstitution des paleoenvironnements et de leur evolution. Les phenomenes de dissolution et de dolomitisation observes suggerent l'existence d'emersions temporaires. Enfin on presente une analyse systematique des miliolina dans laquelle de nouvelles especes sont decrites

Para contribuir a poner en claro la taxonomía de los rudistas americanos se ha creado una base de datos llamada American 2000 y el catalogo de los rudistas de América. La base de datos consta de una parte con toda la bibliografía sobre rudistas americanos y está relacionada con otra parte sobre la sistemática de los rudistas de América. El catalogo de rudistas americanos constituye una guía rápida de géneros y especies de rudistas de América y deja al descubierto grupos problemáticos que necesitan una revisión.
Estas herramientas han servido como base para el estudio de un grupo de rudistas del Cretácico superior en México, en los estados de San Luis Potosí, Guerrero y Chiapas. Para este trabajo sistemático se ha trabajado con material fósil colectado en distintas campañas de campo en México desde el año 1998. Dicha fauna se encuentra en las formaciones El Abra, El Doctor (Turoniense o superior) y Cárdenas (Campaniense-Maastrichtiense) en el estado de San Luis Potosí, la Formación Cuautla en Guerrero (Turoniense) y en las formaciones Ocozocoautla y Angostura (Campaniense-Maastrichtiense) en el estado de Chiapas. Se han estudiado 13 yacimientos en San Luis Potosí de los cuales los yacimientos de Amoladeras y Cárdenas son los más ricos en ejemplares de rudistas. En Guerrero se han encontrado 3 yacimientos y en Chiapas 7.
Se han descrito 26 especies que corresponden a 16 géneros, pertenecientes a las familias Radiolitidae, Plagioptychide, Hippuritidae y Antillocaprinidae. Se describe la estructura de las láminas de la concha de Biradiolites rudissimus que no había sido descrita. Se describe el aparato miocardinal de Durania ojanchalensis, Tampsia floriformis, Thyrastylon adhaerens y Coralliochama gboehmi el cual no era conocido hasta el momento. Se revisa a Macgillavryia nicholasi y se coloca dentro del género Thyrastylon. Se describe a Eoradiolites liratus y a Durania arnaudi ampliamente conocidas en Europa, África y Asia, siendo los primeros registros para el continente americano. Se hace la descripción de un género nuevo perteneciente al grupo de radiolítidos con canales, para la formación señalada como El Abra, en el estado de San Luis Potosí. Se describe la estructura de los poros de la valva izquierda para Praebarrettia sparcilirata que no era conocida hasta el momento. Se describen dos especies ya conocidas en América del género Titanosarcolites, T. giganteus y T. macgillavryi y una especie nueva. Mitrocaprina tschoppi y Antillocaprina pugniformis hasta ahora sólo registradas para la región del Caribe y Biradiolites rudissimus y Praebarrettia sparcilirata sólo registradas para Chiapas, ahora se conocen para la Formación Cárdenas en San Luis Potosí. Durania curasavica encontrada hasta ahora en el Caribe y Chiapas, se da a conocer en yacimientos del estado de Guerrero. Vaccinites macgillavryi conocida en el Caribe y en Guerrero, se encuentra ahora en estratos atribuidos a la Formación El Abra, pero de edad Turoniense o superior. Gracias a este trabajo se ha ampliado el inventario de especies conocidas en la provincia caribeña para la parte central de México (Fm. Cárdenas). Se han identificado especies en San Luis Potosí de edad Turoniense o superior en calizas atribuidas a materiales del Cretácico medio de la Formación El Abra. Se espera que este trabajo contribuya a clarificar la estratigrafía de esta región. Además se pone especial énfasis en la variabilidad intraespecífica de algunas especies, como es el caso de Biradiolites rudissimus y Vaccinites macgillavryi y en el estudio de la estructura de las láminas de la concha en los radiolítidos, lo cual es fundamental para la atribución al nivel de género y especie.
To contribute clarify the american rudists taxonomy a database called American 2000 is created, along with the american rudists catalog. Database is made of two parts, a bibliographic one from all-american rudists, which it is related to a second part about systematics of american rudists as well. American rudists catalog works as a quick sight into the american rudists taxa and at the same time intends to show problematic groups pending to review.
These tools have been the base for an Upper Cretaceous rudists study in Mexico, which crops out in San Luis Potosi, Guerrero and Chiapas states. The paleontological material used for this study comes from a few field trips in Mexico since 1998. This fauna forms part of El Abra, El Doctor (Turonian and upper) and Cardenas (Campanian-Maastrichtian) Formations in San Luis Potosi, Cuautla Formation in Guerrero (Turonian), besides Ocozocoautla and Angostura Formations (Campanian-Maastrichtian) in Chiapas State. There are 13 outcrops in San Luis Potosi, the ones from Amoladeras and Cardenas are the richest in rudists specimens. For Guerrero there are 3 and 7 for Chiapas.
There have been described 26 species belonging to 16 genera, from Radiolitidae, Plagioptychidae, Hippuritidae and Antillocaprinidae families. It is described the shell laminae structure from Biradiolites rudissimus not known until today. It is described the myocardinal apparatus in Durania ojanchalensis, Tampsia floriformis, Thyrastylon adhaerens and Coralliochama gboehmi unknown until now. It is review Macgillavryia nicholasi and place into the genus Thyrastylon. There are described Eoradiolites liratus and Durania arnaudi widely known in Europe, Africa and Asia, been the first report of them in the american continent. It is made the description of a new genus that belongs to the canaliculated radiolitids group, which is assigned to El Abra Formation in San Luis Potosi state. It is described the pores structure of the left valve for Praebarrettia sparcilirata not known until now. There are described two well-known species from America who belong to the genera Titanosarcolites, T. giganteus and T. macgillavryi besides there is a new species. Mitrocaprina tschoppi and Antillocaprina pugniformis just founded in the caribbean region and Biradiolites rudissimus and Praebarrettia sparcilirata only known from Chiapas, now are assigned to Cardenas Formation in San Luis Potosi. Durania curasavica known from the Caribbean and Chiapas, shows up in outcrops in Guerrero state. Vaccinites macgillavryi founded in the Caribbean and Guerrero, now figures in strata assigned to El Abra Formation, but from Turonian age or upper. Thanks to this work the register of known species in the Caribbean province has been expanded for Central Mexico (Cardenas Fm.). There are species identified in San Luis Potosi of Turonian age or upper in limestones attributed to middle Cretaceous materials from El Abra Formation. It is expected that this study lead to clarify the stratigraphy of this region. Besides, it has been taken special attention on intraspecific variability of some species, like is the case of Biradiolites rudissimus and Vaccinites macgillavryi, and in the study of shell laminae structure in radiolitids, what is find to be basic in assigning genus and species.

La localidad surpirenaica de les Collades de Basturs presenta afloramientos extensos y bien expuestos de rocas Santonienses que muestran una sucesión de margas neríticas y calizas someras, localmente con calcarenitas arenosas y que terminan con margas de profundidad. Los cambios laterales de facies son evidentes. Los requiénidos, monopleuridos, caprotínidos, radiolítidos, hippurítidos y plagioptychidos son abundantes en esta sucesión, pero se han notado importantes diferencias en la composición de las asociaciones de rudistas, incluso en la morfología de una sola especie, entre las diferentes facies. Los radiolítidos, hippurítidos y plagioptychidos son los rudistas más abundantes y diversificados en la localidad, además de tener los caracteres morfológicos más complejos. Por esta razón, ellos merecían un profundo tratamiento de paleontología sistemática que incluyera una exhaustiva descripción de todas las características de su concha, su variabilidad intraespecífica y su revisión taxonómica. Las siguientes especies han resultado bien caracterizadas: Radiolites angeiodes Lamarck, R. squamosus d´Orbigny, R. vallispetrosae Astre, Biradiolites acuticostatus (d´Orbigny), B. angulosissimus Toucas, B. beaussetensis Toucas, B. canaliculatus d´Orbigny, B. carezi Toucas, Bournonia excavata (d´Orbigny), Praeradiolites plicatus (Lajard, Négrel y Toulouzan), P. toucasi (d´Orbigny), y Sphaerulites caderensis (Toucas) entre los radiolítidos, Hippurites matheroni Douvillé, H. microstylus Douvillé, H. praecessor Douvillé, H. socialis Douvillé, H. sublaevis Matheron, Hippuritella maestrei (Vidal), H. toucasi (d´Orbigny), Vaccinites beaussetensis Toucas, V. galloprovincialis (Matheron), V. giganteus major Toucas, y V. zurcheri (Douvillé) entre los hippurítidos, y Plagioptychus aguilloni (d´Orbigny) y P. toucasi Matheron entre los plagioptychidos. Como consecuencia de este estudio sistemático, la taxonomía de los rudistas del Santoniense inferior pirenaico ha sido fuertemente simplificada y aclarada. El registro y el análisis posterior de las apariciones de las especies de rudistas, y también las diferencias morfológicas en la concha de una misma especie en facies diferentes contribuye a entender la relación entre los parámetros paleoambientales y la composición faunística de las bioconstrucciones de rudistas en el Cretácico superior.
The south Pyrenean locality Collades de Basturs provides extensive and well exposed outcrops of Santonian rocks displaying a succession of shelf marls and shallow-water limestones, with sandy calcarenites locally, and ending with deep-water marls. Lateral changes of facies are evident. Requienid, monopleurid, caprotinid, radiolitid, hippuritid and plagioptychid rudists are abundant there, but important differences are noticed on the composition of the rudist associations, and even the morphology of single species, among the different facies. Radiolitids, hippuritids and plagioptychids are the most abundant and diverse rudists in the locality, besides having the more complex morphological characters. For that reason, they deserved a deep systematic palaeontology treatment including an exhaustive description of all their shell characters and their intraspecific variability, and their taxonomic revision. The following species resulted well characterized: Radiolites angeiodes Lamarck, R. squamosus d´Orbigny, R. vallispetrosae Astre, Biradiolites acuticostatus (d´Orbigny), B. angulosissimus Toucas, B. beaussetensis Toucas, B. canaliculatus d´Orbigny, B. carezi Toucas, Bournonia excavata (d´Orbigny), Praeradiolites plicatus (Lajard, Négrel y Toulouzan), P. toucasi (d´Orbigny), and Sphaerulites caderensis (Toucas) among the radiolitids, Hippurites matheroni Douvillé, H. microstylus Douvillé, H. praecessor Douvillé, H. socialis Douvillé, H. sublaevis Matheron, Hippuritella maestrei (Vidal), H. toucasi (d´Orbigny), Vaccinites beaussetensis Toucas, V. galloprovincialis (Matheron), V. giganteus major Toucas, and V. zurcheri (Douvillé) among the hippuritids, and Plagioptychus aguilloni (d´Orbigny) and P. toucasi Matheron among the plagiopychids. As a consequence of this systematic study, the taxonomy of the lower Santonian Pyrenean rudists became highly simplified and clarified. The record and subsequent analysis of the rudist species occurrences, and also of the different shell morphologies of the same species, in the different facies contributes to the understanding of the relationship between the palaeoenvironmental parameters and the faunal composition in the Late Cretaceous rudist bioconstructions.

The rudist bivalves were one of the many and varied groups of organisms to be extinguished at the end of the Cretaceous Period. They were a group of bivalves which evolved during Late Jurassic times to dominate the carbonate shelves on the margins of the Tethys Ocean during the Cretaceous Period. Through Late Cretaceous times their diversity climbed to a peak and then entered a period of rapid decline, resulting eventually in the complete extinction of the group. Theories as to the cause of that extinction should clearly be based upon a knowledge of the detailed pattern of the decline. Most important is the question of the timing of the extinction: How long did it take from the peak of diversity to the elimination of the entire group? Is there one main extinction event - or are there several - or is the pattern a gradual decline? In answering these questions this work adopts a new approach to dating end Cretaceous strata by using strontium isotope stratigraphy. The method works by measuring the 87 Sr/86Sr of palaeo-seawater preserved in marine carbonate, such as the thick low-Mg calcite layer of rudist shells. The 87Sr/86Sr of seawater was changing fairly rapidly through time in the latest Cretaceous. The pattern of change has been established in detail using samples from Boreal sequences of which the ages are known with respect to the belemnite stratigraphy. Using this as a standard graph, Tethyan rudist samples have been dated by a comparison of the Sr isotope ratio. The use of Sr isotope stratigraphy has enabled a time axis to be established, against which the ranges of rudist bivalves and of their facies have been ploued. From these data it can be clearly seen that the ranges of many of the established biostratigraphic markers are in error and that the stage boundaries, as defined by the belemnite and planktonic foraminiferal stratigraphies, are offseL When the pattern of rudist diversity is plotted against this time scale it can be seen that, at a specific level, the rudists were at their most diverse at the Campanian/Maastrichtian boundary. Their decline lasted until I almost the end of the Maastrichtian after which the only survivors are Tertiary forms. The decline is related to the disappearance of rudist facies with the end Cretaceous regression, though that graph is slightly displaced from that of rudist diversity. This shows that the rudist extinction is not merely due to non-exposure of terminal Maastrichtian strata.

The Cretaceous (Early Aptian) Shu'aiba Formation, Shaybah field, Saudi Arabia, is 60 km long by 12 km wide and 150 m thick, and is a giant carbonate reservoir. It formed on a regional carbonate ramp bordering an intrashelf basin. The succession consists of a composite sequence of seven high frequency sequences. Sequences 1 and 2 formed a deeper open platform of Palorbitolina-Lithocodium wackestone, with maximum flooding marked by planktic foram mudstone. Sequence 2 built relief over northern and southern blocks, separated by an intraplatform depression. They form the composite sequence TST. The remaining sequences developed a platform rimmed by rudist rudstone backed by rudist floatstone back-bank and lagoonal fine skeletal peloidal packstone; slope facies are fine skeletal fragmented packstone. Aggradational sequences 3 to 5 make up the composite sequence early highstand. Progradational sequences 6 and 7 are the composite sequence late highstand marking the deterioration of the Offneria rudist barrier and deposition of widespread lagoonal deposits, where accommodation may have been created by syn-depositional growth faulting that moved the northern block down. Shu'aiba deposition on the platform was terminated by long-term sea-level fall and karsting.

The succession is dominated by approximately 400 k.y., 4th order sequences and 100 k.y. parasequences driven by long term eccentricity and short term eccentricity respectively, similar to the Pacific guyots of this age. This suggests that early Cretaceous climate may have been cooler and had small ice sheets and was not an ice-free greenhouse world.
Master of Science

El estudio de las plataformas calcáreas del Mesozoico y de los organismos que han contribuido a su desarrollo ha recibido nuevas e importantes aportaciones como ejemplo de respuesta al supergreenhouse climate (clima de superinvernadero) que caracterizó gran parte del Cretácico.
El trabajo se ha centrado en el análisis de las asociaciones de rudistas (Bivalvia, Hippuritoidea) del intervalo Turoniense superior-Campaniense, Cretácico superior, en 12 secciones estratigráficas de plataforma calcárea que afloran en localidades de significado paleontológico y estratigráfico particular de los Apeninos centro-meridionales, Italia y la revisión de colecciones en 12 museos.
Se han estudiado cinco géneros de la Familia Radiolitidae: Biradiolites, Bournonia, Distefanella, Lapeirousella y Radiolites; y en particular nueve especies con especial significado para la estratigrafía del área considerada: Biradiolites angulosus (d'Orbigny, 1847), Biradiolites martelli (Parona, 1911), Bournonia excavata (d'Orbigny, 1842), Bournonia fascicularis (Pirona, 1869), Distefanella salmojraghii Parona, 1901, Distefanella montagnei Sli kovic, 1971, Lapeirousella samnitica (Parona, 1901), Radiolites dario (Catullo, 1834) y Radiolites trigeri (Coquand, 1859).
Se han reinterpretado los caracteres morfológicos de algunas de estas especies y también de algún género, proponiendo, en consecuencia, nuevas descripciones taxonómicas.
El análisis de la valva izquierda en los radiolítidos con valva derecha alargada, ha conducido a reconocer dos morfologías distintas, características de contextos sedimentarios diferentes (Tipo A y Tipo B). El análisis de la tasa de crecimiento de los radiolítidos de valva derecha aIargada y concha delgada y de su relación con la tasa de sedimentación ha conducido a estimar tasas realmente elevadas, por lo que estos radiolítidos se consideran indicadores de elevado acúmulo sedimentario.
Se han distinguido dos tipos de biofacies con radiolítidos de valva derecha alargada, Slender Radiolitid Biofacies (SRB) que se desarrollaron en distintas áreas y ambientes de la zona considerada a lo largo del Cretácico superior, caracterizadas por distintas asociaciones de especies (SRB Tipo A y SRB Tipo B). La distribución de las biofacies con radiolítidos alargados (SRB) en los Apeninos centro-meridionales es asimétrica y está en íntima relación con la compleja fisiografía de las plataformas calcáreas aisladas que se desarrollaron en el área mediterránea central del Tethys del Turoniense al Santoniense. Su distribución permite reconocer un modelo paleoecológico general en el que deben considerarse algunos parámetros atmosféricos y oceanográficos ligados al flujo de la Corriente Circumglobal del Tethys.
Finalmente, los mecanismos de biomineralización adoptados por los bivalvos actuales permiten suponer que la baja relación Mg/Ca y la asociación proteica específica, debe haber jugado un papel importante en la construcción de la concha de los radiolítidos, como lo hace en los bivalvos actuales.
The central Mediterranean area has been investigated by reconstructing the palaeoclimatologic context following the most recent data in literature. Data
asses that surface boundary conditions in late Cretaceous were much different from that of today: sea level much higher (100-200 m higher), medium temperature (higher 14 °C), higher sea water acidity and pCO2 more than 700 ppmv (today 380 ppmv). All these factors deeply modified the global circulation regime. The palaeobiologic answer had to be much different from that of today's biota: rudists with thick calcite shell as radiolitids were well suited to this panorama and represent a keystone in assessing palaeobiologic conditions in a warm climate of the late Cretaceous.
Radiolitid rudist bivalves are widely represented in carbonate successions cropping out in central and southern Italy. In order to analyse rudist assemblages, stratigraphic analysis has been performed in 12 successions from five distant areas.
In the Monti d'Ocre the succession is condensate, spanning from the Aptian to the Campanian, with three datum planes, mainly of platform margin setting. Rudist assemblages give a good biostratigraphic control with caprinids of the Aptian "Urgonian facies", lagoonal facies with Sauvagesia and other molluscs in the middle Cenomanian, Biradiolites angulosus horizons overlied by grain-supported high-energy Distefanella salmojraghii and Lapeirousella samnitica facies.
In the Monti Simbruini, limestones with prevalent mud-supported texture contain radiolitid assemblages composed of beds of elongate Biradiolites angulosus, Radiolites trigeri, Durania arnaudi of late Turonian-Coniacian age, overlaid by assemblages with elongate Radiolites dario and Bournonia excavata of Santonian age. The sedimentary setting is of inner platform. In the Matese Mountains, carbonates of middle Turonian-Campanian age crop out, this is an historical site where Distefanella was instituted. Bioclastic limestones with grain-supported texture bear Distefanella salmojraghii assemblages and other rudist-rich facies.
In the Majella Mountain, the physical scalloped platform margin of the Apulian platform crops out. Well preserved Distefanella assemblages with very elongate specimens (up to 40 cm) in bioclastic grain-supported limestone have been studied in situ and found in reprised blocks as olistolithes in the pelagic scaglia.
In Cilento area, radiolitids have been found in two distinct assemblages:
Radiolites trigeri, Durania arnaudi, Biradiolites martelli, Bournononia gardonica,
Biradiolites angulosus (CO Assemblage of late Turonian-Coniacian) and Radiolites dario, Bournonia fascicularis, Sauvagesia tenuicostata (SA assemblage of late Coniacian-Santonian age). Both associations are embedded in mud-supported limestone of inner platform setting and are composed of elongate specimens.
Specimens collected in outcrops and others studied in museum's collections allowed to update palaeontologic information on five genera and nine species and to re-describe genus Distefanella. The biomineralization stategy adopted by these extinct bivalves with thick calcite shells, could be analogous to that of living molluscs, eventually involving protein associations with aspein and caspartin.
During the Late Cretaceous, different sedimentary contexts show peculiar radiolitid assemblages; the rudist biofacies distribution is strongly influenced by the palaeogeographic setting and by the global palaeo-oceanic circulation pattern that, in the central Mediterranean area, was mainly east-to-west directed.
R E S U L T S
The study performed on rudist radiolitid assemblages of the late Turonian-Campanian interval, Late Cretaceous, in 12 stratigraphic sections sampled in the central-southern Apennines, Italy, and the revision of fossil collections in 12 museums, lead to some conclusions on the palaeontology of these bivalves. Nine species with particular significance for the stratigraphy of the considered area, belonging to five genera of the Family Radiolitidae have been studied: Biradiolites angulosus (d'Orbigny, 1847), Biradiolites martelli (Parona, 1911), Bournonia excavata (d'Orbigny, 1842), Bournonia fascicularis (Pirona, 1869), Distefanella salmojraghii Parona, 1901, Distefanella montagnei Sli kovic, 1971, Lapeirousella samnitica (Parona, 1901), Radiolites dario (Catullo, 1834) and Radiolites trigeri (Coquand, 1859).
The morphologic features of some of these species, and also of some genera, have been reinterpreted. New taxonomic attributions have been proposed.
- Bournonia fascicularis (Pirona, 1869). The species description has been completed as it was poorly known; it has been found in many Coniacian-Santonian successions of Italy. Its generic attribution has been justified.
- Biradiolites martelli (Parona, 1911). Two morphotypes have been distinguished: morphotype A with elongate costae and morphotype B with short costae. Its generic attribution has been justified. The revision work lead to consider that the species of genus Milovanovicia Pol ak, 1967 can be ascribed to B. martelli for the whole of its features, so that this genus is unnecessary.
- Distefanella Parona 1911. The type material has been revised, reinterpreting the diagnostic features of the genus. It has been ascertained synonymy among species originally ascribed. The study of the whole literature published after, and new collected material allowed to reduce the 25 known species to only two, Distefanella salmojraghii Parona, 1911 and Distefanella montagnei Sli ković, 1971, that are different for the development and grade of invagination of the radial bands.
- Its attribution to genus Lapeirousella Milovanović, has been definitively ascertained. The analysis of the left valve in radiolitids with elongate right valve, thin shell, and deeply anchored in the substrate, together with the study of the sediment where they are contained, lead to recognize two distinct morphologies, each typical of different sedimentary context, of inner platform/ramp and platform margin respectively.
- Type A, with left valve flat or smoothly concave, provided with a little developed myocardinal apparatus that is considered to be well adapted in environments with moderate to low energy.
- Type B, with left valve high, cupuliform, provided with a myocardinal apparatus that, with two teeth very large and myophores laterally well developed, forms a nearly tubular structure that, inserted in the right valve, gives good mechanic strength at the area near the commissure. It is considered well adapted to prevent the accumulation of sediment on the valve itself, moreover to be resistant in an environment under moderate to high energy.
The analysis of the growth rate of radiolitids with slender and thin shelled right valve, and their relation with the sedimentation rate, lead to approximate rates really high, up to >4 mm/yr, so that these radiolitids are considered as indicators of high sediment accumulation.
Two types of biofacies with slender radiolitids have been recognized, (Slender Radiolitid Biofacies, SRB) that developed in different zones and environments of the considered area in the late Cretaceous, characterized by different species assemblages:
- SRB Type A, in limestone with mainly mud-supported texture, frequently of algal-bacterial sedimentation, of inner platform and ramp in the Simbruini Mt., Ausoni Mts. and in Cilento. The carbonate productivity in this context is extremely high if comparing to actual models (up to 20 times higher).
In the late Turonian-Coniacian the fossiliferous assemblage is marked by: Biradiolites angulosus d'Orbigny, Biradiolites martelli (Parona) morphotype A, Bournonia excavata (d'Orbigny), Durania arnaudi (Choffat), Radiolites trigeri (Coquand) and Sauvagesia sp. In the Coniacian-Santonian by: Bournonia fascicularis (Pirona) and Radiolites dario (Catullo).
- SRB Type B, in limestone with texture mainly grain-supported, bioclastic, of platform margin in the Matese Mts. and in the Majella Mt. The carbonate productivity can be compared to that recorded in the actual most productive barrier reefs. In the late Turonian-Santonian the fossiliferous assemblage is marked by: Distefanella salmojraghii Parona and Lapeirousella samnitica (Parona).
It has been ascertained that the slender radiolitid biofacies distribution (SRB) in the central-southern Apennines is asymmetric:
- T- he SRB Type A crop out in the Simbruini Mts., Ausoni Mts. and in the Cilento area, localized in the western side of the Apenninic belt.
- The SRB Type B is well developed in the bioclastic successions that crop out in the Monti d'Ocre, Matese Mts. and in the Majella Mt., localized in the eastern side of the belt.
Both the SRB Type A and SRB Type B are intimately linked to the complex physiography of the isolate carbonate platforms that developed in the central Mediterranean area of the Tethys from the Turonian up to the Santonian. Its distribution allows to recognize a general palaeoecologic model where, to explain the asymmetry, some oceanographic and atmospheric parameters must be considered, linked to the Tethys Circumglobal Current flux that, in the Late Cretaceous, was from the East to the West in the latitude corresponding to the central Mediterranean area (between 15° and 25° of latitude).
The examination of the biomineralization mechanisms adopted by the living bivalves allow to hypothesize that the low Mg/Ca ratio and the specific protein assemblage have had a key role in the formation of the radiolitid shell, as it is in the living bivalves. Particularly, aspein and caspartin might have acted as amplifiers in calcite shell biomineralization process and as palaeobiologic response of these bivalves to the supergreenhouse climate context of the Cretaceous.

Ce travail concerne les formations du cretace superieur du massif du gargano et des murges (italie meridionale). L'etude stratigraphique, basee sur la faune de foraminiferes et de rudistes, permet de mettre en evidence plusieurs discontinuites dans la serie et une tendance a l'emersion marquee egalement par la formation de bauxite. Les depots sont caracteristiques de milieux de plateforme carbonatee et de talus. Les breches et depots bioclastiques du talus correspondent a des mises en place par ecoulements ou glissements gravitaires controles par des phenomenes tectoniques en relation avec la structuration de la marge. Les phenomenes diagenetiques sont egalement etudies

The study (MS, diploma thesis) is based on more than 1500 rudist samples from the Upper Cretaceous sediments of localities Písečný vrch and Na Stínadlech (near Teplice). Investigated samples come mainly from the collection of A. H. Fassel and were collected at the end of the 19th century, currently stored in the Regional museum in Teplice and National museum in Prague. The rudist shells were determined by generic and species levels, including five genera and eight species. The stratigraphic age of both localities has been a subject of discussion since the second half of the 19th century. In the recent decades, the opinion on the lower turonian age prevailed. However, five of the eight species present in the studied localities demonstrate the upper cenomanian age of the assemblages, making them probably the oldest known rudist-corals assemblages of its kind. The palaeoecological analysis and the ecological relationships proposal for the studied localities is based on the research in literature on palaeoecology and evolution of the rudists, also presented in the study. Key words: Bohemian Cretaceous Basin, Cenomanian - Turonian, rudists, corals, palaeoenvironment, Teplice rhyolite

O presente trabalho de projeto tem como objetivo criar uma rota de âmbito patrimonial, de modo a dar a conhecer a novos públicos, para além dos especializados, uma indústria que se desenvolve através da extração, transformação e do recurso natural - os calcários microcristalinos do maciço anelar sub-vulcânico de Sintra, região de Pero Pinheiro, que no concelho de Sintra, é um elemento intrínseco e identitário da zona geográfica em estudo da freguesia de Almargem do Bispo, Pero-Pinheiro e Montelavar. Ao longo de séculos, esta indústria, à escala de um território, vive entre o desenvolvimento da tecnologia e a memória das fábricas e pedreiras desativadas, que integram uma paisagem industrial única preenchida pelo valor social e afetivo de quem tem o conhecimento do "saber fazer".
The present project work aims to create a heritage route, in order to make known to new publics, in addition to the specialized ones, an industry that develops through the extraction, transformation and the natural resource - the microcrystalline limestones of the sub-volcanic of Sintra, Pero Pinheiro region, which in the municipality of Sintra is an intrinsic and identity element of the geographical area under study in the parish of Almargem do Bispo, Pero-Pinheiro and Montelavar. Over the centuries, this industry, at the scale of a territory, lives between the development of technology and the memory of deactivated factories and quarries, which integrate a unique industrial landscape filled with the social and affective value of those who have the knowledge of.

The Mural Limestone, located in the Mule Mountains to the northeast and southeast of Bisbee, Arizona provides an exceptional outcrop analog for time-equivalent productive reservoirs in the Albian Glen Rose patch-reef play of the Maverick Basin. The Mural Limestone is exposed in a number of folds and east-dipping fault blocks in the Grassy Hill and Paul Spur localities in the Mule Mountains and represents a remnant of a south-facing distally-steepened carbonate ramp that prograded into the Chihuahua Trough in Albian time. This study documents the detailed facies architecture and sequence stratigraphic setting of a multicyclic patch-reef and its associated ramp interior facies at the Paul Spur and Grassy Hill localities, respectively. Small mud-dominated coral-algal buildups (~5 m thick) and tabular biostromes (up to 1.5 m thick) consisting of rudist floatstones are common in the bedded ramp interior carbonates at the Grassy Hill locality in the Mule Mountains 10 km landward of the Paul Spur reef. Buildups in this area are flanked by weakly-cyclic and well-bedded skeletal mud- and grain-dominated packstones. At the Paul Spur locality, Mural facies consist of a 10-35 m thick patch-reef with four distinct reef communities: microbial-Microsolena framestone, algal-Actinastrea boundstone, branching coral-skeletal framestone and caprinid-requienid floatstone. Measured reef dimensions show a distinct windward-leeward margin with reef frame facies extending ~70 m from the margin and extensive leeward rudstone debris and grainstone shoal facies extending a distance of 870 m. Reef and backreef shoal facies exhibit low preserved porosity but petrographic analysis of backreef grainstones shows that primary porosity and permeability was present. These extensive reservoir-prone shoals may be a suitable reservoir target similar to flank rudstones and grainstones of the Maverick Basin reefs. Three aggradational to retrogradational cycles of reef growth are evident at the Paul Spur locality. Retrogradational stacking is consistent with that of time-equivalent Lower Glen Rose patch-reefs in the Maverick Basin of Texas, which suggests a eustatic driver for stratigraphic architecture along the Bisbee/Comanche shelf. Backstepping of reef frame facies in Cycle 3 is interpreted to be time-equivalent to patch-reef development at the Grassy Hill locality.
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Carbonate platforms contain a wealth of information regarding the changing biota, sea level, ocean-chemistry, and climate of the Cretaceous Period. The Comanche platform of the northern Gulf of Mexico represents a vast, long-lived carbonate system that extended from west Texas through the Florida panhandle. In central and south Texas, excellent outcrops and an extensive suite of subsurface data provide an opportunity to document the evolution of this system, from the shoreline to the shelf-margin and slope. This study examines the changing facies, platform morphologies, and shelf-margin architectures of the mixed carbonate-siliciclastic, middle-Hauterivian to lower-Campanian interval. Stratigraphic results are integrated with stable-isotope geochemistry to document the detrimental effects of oceanic anoxic events on the carbonate platform. Seven second-order, transgressive-regressive supersequences of 3-14 Myr duration are defined in south Texas using sequence stratigraphic analysis of shelf-interior facies successions. Second-order supersequences are subdivided into several third-order depositional sequences of 1-3 Myr duration. In these sequences, facies proportions and stratal geometries of the shelf-interior are found to be the result of changing platform morphology and temporal evolution from distally-steepened ramp to rimmed-shelf depositional profiles. Shelf-margin trajectories, stratigraphic architectures, and facies proportions are a function of long-term accommodation trends expressed in second-order supersequences. These characteristics are modified by lateral variability in the underlying structural/tectonic setting and localized syndepositional faulting. The stratigraphic equivalents of oceanic anoxic events 1a, 1b, 1d, 2, and 3 are documented in the Cretaceous section of south Texas. These oceanic anoxic events coincided with maximum flooding zones of supersequences and are linked to carbonate platform drowning events on four separate occasions. The occurrence of oceanic anoxic events is found to be a fundamental driver of carbonate platform morphology, faunal composition, and facies evolution in transgressive-regressive supersequences of the northern Gulf of Mexico.
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