31 research outputs found
Pliocene marine Bivalvia of Vale do Freixo (Pombal, Portugal) : updated taxonomic list and discussion
The exceptional Pliocene marine faunal assemblages of west central Portugal have been known since the late 19th century. They include highly diverse molluscan faunas whose study is far to be completed. Discovered nearly 40 years ago, Vale do Freixo (Carnide, Pombal) is perhaps the most outstanding fossil site. Neverthless, the bivalves remain relatively unknown. This study focuses on the taxonomy of this relevant group of marine Mollusca. The research, based on a detailed sampling of three fossiliferous beds from the Carnide Formation, yielded a list of 85 species belonging to 75 genera and 32 families. Forty-three species are new for the Carnide area and twenty-three are reported for the first time in the Portuguese Pliocene, increasing to 115 the number of known species in the Mondego Basin in the Beira Litoral
The biota of the Upper Cretaceous site of Lo Hueco (Cuenca, Spain)
The Late Cretaceous (Campanian-Maastrichtian) fossil site of Lo Hueco was recently discovered close to the village of Fuentes (Cuenca, Spain) during the cutting of a little hill for installation of the railway of the Madrid-Levante high-speed train. To date, it has yielded a rich collection of well-preserved Cretaceous macrofossils, including plants, invertebrates, and vertebrates. The recovered fossil assemblage is mainly composed of plants, molluscs (bivalves and gastropods), actinopterygians and teleosteans fishes, amphibians, panpleurodiran (bothremydids) and pancryptodiran turtles, squamate lizards, eusuchian crocodyliforms, rhabdodontid ornithopods, theropods (mainly dromaeosaurids), and titanosaur sauropods. This assemblage was deposited in a near-coast continental muddy floodplain crossed by distri-butary sandy channels, exposed intermittently to brackish or marine and freshwater flooding as well as to partial or total desiccation events
Upper Barremian−lower Aptian charophyte biostratigraphy from Arrifes section (Algarve Basin, Southern Portugal): correlation with dinoflagellate cyst biostratigraphy
The Arrifes section (Algarve Basin, Southern Portugal) has been studied from the viewpoint of charophyte biostratigraphy. The previous sedimentological studies in this section showed that it is built of the interbedding of continental and marine facies that contain both marine and continental palynomorphs (pollen, spores, and dinoflagellates), providing an excellent sedimentary context to perform direct correlations between marine and continental domains. In the present work, the identified charophyte biozones have been correlated with dinoflagellate biozones previously recognized in the Arrifes section, being the first time that these two biochronologies can be directly correlated. From the charophyte biostratigraphy viewpoint, two assemblages are distinguished. The older one is found between 65 and 135 m of the stratigraphic section, and it is composed of the species Echinochara lazarii, Atopochara trivolvis var. triquetra, A. trivolvis var. trivolvis, Clavator grovesii var. jiuquanensis, Clavator harrisii var. harrisii, C. harrisii var. reyi, and C. harrisii var. zavialensis. This assemblage belongs to the upper Barremian-lower Aptian Clavator grovesii var. jiuquanensis Eurasian biozone and also to the Ascidiella cruciata-Pseudoglobator paucibracteatus European biozone and it is described in beds with the dinoflagellate cyst Subtilisphaera scabrata (lower to lowermost upper Barremian) and Odontochitina operculata (from upper Barremian upwards). The younger charophyte assemblage is found between 135 and 155 m of the stratigraphic section, and it is composed of the species A. trivolvis var. trivolvis, Clavator grovesii var. corrugatus, Clavator harrisii var. harrisii, C. harrisii var. reyi, and C. harrisii var. zavialensis. This assemblage belongs to Clavator grovesii var. corrugatus biozone, previously assigned to upper Aptian (Clavator grovesii var. lusitanicus biozone). However, in the Arrifes section, this assemblage is found in beds assigned to the dinoflagellate cyst Odontochitina operculata (from upper Barremian-lower Aptian). The direct correlation of the base of the C. grovesii var. corrugatus biozone with the dinoflagellate cyst O. operculata, indicates that the base of the Clavator grovesii var. corrugatus biozone is in the upper lower Aptian, which is slightly older than was previously suggested, and it is extended until the middle Albian
New palaeontological data on the Upper Cretaceous of Pálmaces de Jadraque and Veguillas (Guadalajara, Spain)
Con el fin de actualizar y ampliar los trabajos paleontológicos previos sobre el Cretácico Superior del Norte de Guadalajara, se han estudiado dos columnas estratigráficas en las localidades de Pálmaces de Jadraque y Veguillas. Las facies analizadas representan la transgresión y el comienzo de la regresión del Cenomaniense superior-Turoniense inferior. El material paleontológico recogido se ha estudiado sistemáticamente, identificándose: Seis taxones de bivalvos, dos taxones de gasterópodos, dos taxones de cefalópodos y dos taxones de equinoideos.In order to update and expand the previous palaeontological studies about the Upper Cretaceous of the North of Guadalajara two stratigraphic sections have been studied near the villages of Pálmaces de Jadraque and Veguillas
(Figs. 1, 2). Studied facies correspond to three different formations (Arenas, arcillas y calizas de Santa María de
las Hoyas, Margas de Picofrentes and Dolomías de la Ciudad Encantada) that represent the transgression and the beginning of the regression of the upper Cenomanian-lower Turonian. The collected palaeontological material has
been studied systematically and thirteen taxa have been identified: six bivalves, two gastropods, two cephalopods and two echinoids. Besides, two different biotic associations have been identified. The first one corresponds to a relative shallow environment with a fauna of epifaunal bivalves and gastropods that are located in the Santa María de las Hoyas Formation. The second represents a deeper environment with infaunal bivalves, gastropods, ammonoids and echinoids, and is located in the Picofrentes Formation.Depto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEMinisterio de Ciencia e Innovación (MICINN)pu
The Cenomanian-Turonian of Tamajón (Guadalajara, Spain): geological context, fossil content and palaeoenvironmental interpretation
La sección del Cenomaniense-Turoniense de Tamajón, con un alto valor científico, educativo y divulgativo, incluye las formaciones Utrillas, Villa de Vés y Picofrentes, y la parte inferior de la Formación Ciudad Encantada. Contiene huellas de vertebrados (cocodrilomorfos, un posible dinosaurio terópodo y peces), otros icnofósiles (principalmente Thalassinoides), plantas vasculares, una considerable diversidad de invertebrados, incluyendo corales, briozoos, braquiópodos, bivalvos, gasterópodos, cefalópodos, equinodermos (equinoideos) y crustáceos decápodos, y algunos restos de peces y reptiles marinos, entre otros fósiles. El conjunto de la sección registra una transgresión marina y el inicio de una regresión, incluyendo el paso de un medio continental y de transición, a un entorno claramente marino con abundantes invertebrados, que finalmente fue afectado por un descenso eustático.The Cenomanian-Turonian section (Upper Cretaceous) of Tamajón (Guadalajara, Spain) combines high scientific, educational and outreach values. Their materials unconformably lie onto Triassic deposits in Buntsandstein facies, being included into the Utrillas, Villa de Vés and Picofrentes formations, and the lower part of the Ciudad Encantada Formation. The section contains beds showing several tracks (occasionally trackways) of numerous crocodyliforms, a possible theropod dinosaur and some fishes, and different ichnofossils (mainly bioturbations Thalassinoides) usually caused by invertebrates. It also yields some fragments of trunks and branches of vascular plants, a high diversity of invertebrates, including scleractinian corals, bryozoans, brachiopods, bivalves (a high variety, including ostreids and rudists), gastropods, cephalopods (mainly ammonoids), echinoderms (echinoids), and decapod crustaceans, together with osteichtian and chondrichthyan fishes, and marine reptiles, among many other remains. The whole section records a marked marine transgression and the beginning of a regression, showing the change from a terrestrial and transitional setting, with vascular plants and crocodyliforms (Utrillas and Villa de Vés formations), to a fully marine environment, extraordinary rich in molluscs and other invertebrates (Picofrentes Formation), which finally was affected by a notable eustatic fall (lower part of Ciudad Encantada Formation).Depto. de Geodinámica, Estratigrafía y PaleontologíaDepto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEMinisterio de Economía y Competitividad (MINECO)Diputación de GuadalajaraUniversidad Complutense de Madridpu
A remissão como forma de extinção das obrigações
A presente dissertação versa sobre uma das formas de extinção das obrigações além do cumprimento individualizadas pelo Código Civil português, a remissão, a qual consiste no contrato pelo qual credor e devedor acordam na extinção da dívida. O aspeto mais impressivo da remissão é a circunstância de o credor voluntariamente renunciar ao direito de crédito sem obter qualquer contrapartida. Por esse motivo, a remissão é uma forma de extinção das obrigações que não realiza o interesse do credor sendo a que mais se afasta do paradigmático cumprimento. Sem embargo desta sua natureza, que verdadeiramente individualiza a remissão face às demais formas de extinção das obrigações, a figura nunca despoletou o interesse da doutrina nem da jurisprudência nacionais. Quer essa circunstância seja associável à aparente simplicidade da figura, quer seja um resultado do reduzido número de litígios com ela relacionados, a verdade é que a remissão vive timidamente acantonada em obras gerais de Direito das obrigações e afastada dos esquemas estruturados de aplicação do Direito. No presente escrito, procura-se contribuir para o desenvolvimento da figura, aprofundando a sua noção, os seus efeitos, o regime jurídico que lhe é aplicável e as características essenciais do seu objeto.This master’s thesis addresses one of the manners, other than performance, by which obligations are discharged identified by the Portuguese Civil Code the remission of debt, which is the agreement pursuant to which creditor and debtor agree on the cancellation of the debt.
The most striking aspect of the remission of debt is the fact that the creditor voluntarily waives its right without any consideration in connection thereto. For this reason, remission of debt is a manner of discharge that does not fulfill the creditor's interest and is the form that is farthest from the paradigmatic performance. Despite this
nature, which truly differentiates the remission of debt from all other manners of discharge, the figure did not awaken the interest of national legal doctrine or jurisprudence. Whether this circumstance can be associated with its apparent simplicity of the figure or whether it is a result of the small number of disputes related to it, the fact is that remission of debt is cornered in law of obligations’ textbooks and kept away from
the structured schemes of application of law.
In this thesis, we seek to contribute to the development of the remission of debt, deepening its concept, its effects, the legal regime applicable to it and the essential features of its subject matter
Estratigrafia e paleobiologia do cenomaniano-turoniano: o significado do eixo da Nazaré-Leiria-Pombal.
Tese de doutoramento em Geologia (Estratigrafia e Paleontologia) apresentada à Fac. de Ciências e Tecnologia da Univ.de CoimbraA dissertação apresentada inclui o estudo estratigráfico da Formação Carbonatada, um extenso corpo sedimentar de natureza essencialmente calcária e de idade cretácica (andares Cenomaniano e Turoniano - cerca de 98 a 92 milhões de anos), que se distribui pelas regiões do Baixo Mondego e da Nazaré-Leiria-Ourém. Estas duas regiões estão separadas por um importante eixo de fracturação NE-SW (falha da Nazaré), cujo rejogo levou a que se diferenciassem vários domínios de sedimentação carbonatada marinha a Norte e a Sul. Assim, entre a Nazaré e Leiria desenvolveu-se, durante o Cenomaniano superior, um complexo de altos fundos com bioconstrucções de rudistas e/ou corais, passando a uma vasta área lagunar na região de Ourém. A Norte do eixo referido, estes domínios passavam a fácies carbonatadas e greso-carbonatadas com amonites, traduzindo um meio mais aberto às influências marinhas e limitado a oriente por planícies litorais e aluviais.
O estudo estratigráfico efectuado foi acompanhado por uma revisão sistemática das faunas de amonites e inoceramídeos portuguesas, seguido de uma análise biostratigráfica, conducente ao estabelecimento de um quadro biozonal.
Também os povoamentos macro-bentónicos das duas áreas foram estudados do ponto de vista paleobiológico e ecozonal (variações espaciais e temporais das numerosas associações fósseis reconhecidas, na sua maior parte compostas por corais, gastrópodes, bivalves, briozoários, equinídeos, serpulídeos e crustáceos decápodes).
Todos estes dados foram, por fim, conjugados com vista à elaboração de diversas cartas paleobiogeográficas, reconstituído a evolução espaço-temporal da região estudada durante este intervalo do Cretácico superior, caracterizado pela permanência do domínio marinho em grande parte do actual território português
First occurrence of Cardilia michelottii Deshayes, 1844 (Bivalvia, Cardiliidae) in the Iberian Pliocene
The family Cardilidae groups a small number of bivalve species from the superfamily Mactroidea, which have been scarcely found and have a known stratigraphic range from the middle Eocene to the present day. From these stand out Cardilia michelottii Deshayes, 1844, as an extinct valid species only previously knew from the Italian Peninsula, where it has been recorded from the Miocene of Emilia-Romagna, the Pliocene of Tuscany and Piedmont, and the Pleistocene of Lazio. The first finding of this species outside the Italian ranges is here reported from a single, but well-preserved left valve collected from the lower Piacenzian molluscan assemblage of Vale de Freixo fossil site (Pombal, West Portugal), in the Pliocene Mondego Basin. This allows to extend the known biogeographic range of this thermophilic species to the Iberian Peninsula, and also to reduce the geographical gap between the Neogene to present-day West African and Mediterranean occurrences of this morphologically very distinctive genus of warm shallow-water bivalve assemblages.publishersversionpublishe