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Les travaux faits sur le terrain et les interprétations cartographiques de ces dernières années, montrant la pertinence des observations de Paul Choffat au siècle dernier, permettent de préciser l'échelle stratigraphique et de mieux distinguer les phases de l'histoire tectonique de la structure de Serra de EI-Rei. En attendant la publication d'une cartographie très détaillée mettant en évidence le détail des déformations tectoniques, il faut souligner la dissymétrie des deux flancs de cette structure ainsi que le rôle de certaines failles transverses. Sur son flanc nord, la série liasique, allant des dolomies du Lias inférieur au Toarcien inférieur ou moyen, est recouverte stratigraphiquement et en légère discordance par le "Lusitanien" qui remanie à sa base des éléments du Toarcien inférieur ou moyen. Sur son flanc sud, dans la partie centrale, la série stratigraphique liasique est comparable à celle de l'autre flanc, mais les dépôts du Toarcien, plus complets, sont affectés au cours de la zone à Meneghinii par des perturbations synsédimentaires avec fossiles brisés et/ou remaniés et des réductions d'épaisseur. Plus à l'Est, le Toarcien est très réduit et (tectoniquement?) en contact avec le Dogger. Au Sud-Ouest en revanche, prés de Bolhos, la série toarcienne est plus complète et couronnée par l'Aalénien inférieur, mais tronquée par un contact oblique N-S, repris par la tectonique récente. Sur ce flanc, le Bajocien inférieur est représenté mais peu épais; il est suivi par le Bajocien supérieur, le Bathonien et le Callovien très développés qui sont recouverts par un "Lusitanien" épais, très différent de celui du flanc nord. Cette série du Jurassique moyen et supérieur a été décrite dans la thèse de Christiane Ruget (1963). La structure de Serra de EI-Rei constitue une sorte de raccord E-W entre les importantes structures (diapiriques ?) méridiennes de Caldas da Rainha au NE et de Bolhos au SW. II s'agit d'une structure de tectonique distensive, en demi-graben, d'âge jurassique, qui est responsable de la dissymétrie des séries lithostratigraphiques sur ses deux flancs; au Miocène, pendant la compression bétique, cette structure a subi une inversion en constriction. Un modèle de l'évolution sédimentaire du secteur est présenté.

The evolution of the Lusitanian Basin, localized on the western Iberian margin, is closely associated with the first opening phases of the North Atlantic. It persisted from the Late Triassic to the Early Cretaceous, more precisely until the end of the Early Aptian, and its evolution was conditioned by inherited structures from the variscan basement. The part played by the faults that establish its boundaries, as regards the geometric and kinematic evolution and the organization of the sedimentary bodies, is discussed here, as well as with respect to important faults transversal to the Basin. A basin evolution model is proposed consisting of four rifting episodes which show: i) periods of symmetrical (horst and graben organization) and asymmetrical (half graben organization) geometric evolution; ii) diachronous fracturing; iii) rotation of the main extensional direction; iv) rooting in the variscan basement of the main faults of the basin (predominantly thick skinned style). The analysis and regional comparison, particularly with the Algarve Basin, of the time intervals represented by important basin scale hiatuses near to the renovation of the rifting episodes, have led to assume the occurrence of early tectonic inversions (Callovian–Oxfordian and Tithonian–Berriasian). The latter, however, had a subsequent evolution distinct from the first: there is no subsidence renovation, which is discussed here, and it is related to a magmatic event. Although the Lusitanian Basin is located on a rift margin which is considered non-volcanic, the three magmatic cycles as defined by many authors, particularly the second (approx. 130 to 110 My ?), performed a fundamental part in the mobilization of the Hettangian evaporites, resulting in the main diapiric events of the Lusitanian Basin. The manner and time in which the basin definitely ends its evolution (Early Aptian) is discussed here. Comparisons are established with other west Iberian margin basins and with Newfoundland basins. A model of oceanization of this area of the North Atlantic is also presented, consisting of two events separated by approximately 10 My, and of distinct areas separated by the Nazaré fault. The elaboration of this synthesis was based on: - information contained in previously published papers (1990 – 2000); - field-work carried out over the last years, the results of which have not yet been published; - information gathered from the reinterpretation of geological mapping and geophysical (seismic and well logs) elements, and from generic literature concerning the Mesozoic of the west iberian margin.

A existência de um inventário nacional de património geológico é fundamental para se poderem implementar estratégias de geoconservação. Este trabalho apresenta a metodologia usada no desenvolvimento do mais completo inventário de geossítios. realizado até ao momento em Portugal, assim como os principais resultados obtidos. O inventário vai integrar o Sistema de Informação do Património Natural e o Cadastro Nacional dos Valores Naturais Classificados, ambos geridos pelo Instituto de Conservação da Natureza e da Biodiversidade.

A existência de um inventário nacional de património geológico é fundamental para se poderem implementar estratégias de geoconservação. Este trabalho apresenta a metodologia usada no desenvolvimento do mais completo inventário de geossítios, realizado até ao momento em Portugal, assim como os principais resultados obtidos. O inventário vai integrar o Sistema de Informação do Património Natural e o Cadastro Nacional dos Valores Naturais Classificados, ambos geridos pelo Instituto de Conservação da Natureza e da Biodiversidade., The existence of a national inventory of the geological heritage is of paramount importance for the implementation of a geoconservation strategy. This paper presents the methodological approach used to produce the most complete geosites inventory in Portugal, so far, and the obtained results. This inventory will be uploaded into the National Database of Natural Heritage managed by the Portuguese authority for nature conservation., Este trabalho é apoiado pela Fundação para a Ciência e a Tecnologia, através do financiamento plurianual do CGUP e do projecto de investigação “Identificação, caracterização e conservação do património geológico: uma estratégia de geoconservação para Portugal” (PTDC/CTE-GEX/64966/2006)., info:eu-repo/semantics/publishedVersion

A Cadeia da Arrábida é a estrutura morfotectónica orogénica, constituída por empilhamentos de cavalgamentos, mais ocidental de todo o orógeno alpino da área emersa da placa litosférica Eurásia. Atentando apenas nos relevos orogénicos alpinos da área emersa de Portugal, as suas estruturas e morfologia tornam-na no mais elegante exemplo de tectónica orogénica alpina em Portugal. A Serra de Sintra constitui um relevo associado à intrusão do Complexo Ígneo de Sintra de idade neo-cretácica e ao cavalgamento frontal de idade cenozóica, com vergência para Norte que se estende desde as proximidades do rio Tejo, passando pela base da vertente norte da Serra de Sintra, continuando mar adentro. Olhando para a continuação imersa da Margem Continental Portuguesa vê-se que estes relevos não estão isolados, mas antes fazem parte dum grupo de três outras estruturas compressivas que acomodaram o encurtamento orogénico resultante da colisão África-Eurásia ocidentais no segmento sudoeste ibérico, o Banco do Gorringe, os Montes de Avis e o Planalto de Marquês de Pombal. Todas estas estruturas se constituem como estruturas anticlinais, mais ou menos simples, a tecto dum cavalgamento com transporte para noroeste ou oeste-noroeste. Na face meridional de Portugal, mais próxima do limite de placas, as estruturas de deformação compressiva resultantes da orogenia alpina encontram-se representadas na Bacia do Algarve e, mais a sul, pelo Banco do Guadalquivir. Todas estas estruturas se formaram no âmbito da orogenia alpina, consequência dum contexto cinemático de aproximação das placas litosféricas Eurásia e África, cujas manifestações morfotectónicas e sedimentares se começaram a manifestar no Cretácico Superior após o Cenomaniano. A distribuição espacio-temporal da deformação orogénica no segmento mais ocidental do orógeno é heterogénea e extremamente complexa. Por exemplo, em Portugal – segmento autóctone do orógeno alpino - as principais estruturas compressivas alpinas mais antigas datam do Cretácico superior e na região de Lisboa-Sintra de idade paleogénica. Contudo as estruturas de maior envergadura morfológica são de idade miocénica (serra da Arrábida, Banco do Gorringe, Montes de Avis) e mesmo de reactivação mais recente (Falha e planalto do Marquês de Pombal, Falha da Ferradura e Banco de Guadalquivir. A mesma heterogeneidade espacio-temporal se verifica em segmentos alóctones como no orógeno Bético-Rifenho, cujo arco orogénico frontal se vem propagando para oeste desde o Cretácico superior, simultaneamente cavalgando para norte e para sul, as margens continentais do sul de Espanha e norte de África. Esta migração orogénica está simultaneamente associada a colapso orogénico e distensão nas áreas internas do orógeno (Mar de Alborán), o que tem constituído um dos paradoxos da deformação orogénica alpina mais desafiantes das últimas décadas e para cuja solução se têm proposto mecanismos de delaminação tectónica da base da litosfera ou retro-rolamento da placa subductada.

Cartografia Geológica Aplicada a Áreas Urbanas This paper presents a synthesis of the work related to the revision of sheets of the 1:50 000 geological map of Portugal for the production of a digital version, at different scales, for the Area of Lisbon. Our case study refers to the Mesozoic units. Besides a short introductory approach to previous works carried out by field geologists on the past, considerations about methodologies and difficulties related to the activity of surveying are discussed; in particular, what concerns the correlations between lithostratigraphic units derived from local differentiations and the need of normalization in the process of production of geological maps, at different scales. A brief geodynamic framework of the Lusitanian Basin where those units concern is presented, in order to contextualize the discussion.

Um estudo gravimétrico realizado recentemente, mostra que o maciço de Sintra é um lacólito, com espessura máxima preservada de rocha ígnea, na região central, de cerca de 1 km. Estudos de Análise da Susceptibilidade Magnética realizados na mesma ocasião em 56 sítios de amostragem no interior do maciço ígneo, põem em evidência, no que respeita à intrusão granítica, uma foliação magmática com orientação irregular e uma lineação magnética k1 com uma direcção dominante NNE-SSW, consistente com um modelo de intrusão definido por uma zona de alimentação magmática com orientação WNW-ESE, em conformidade com o alinhamento dos mínimos gravimétricos no mapa de anomalias de Bouguer construído. A intrusão gabro-sienítica carece de padrão geométrico de ASM, salvo no contacto com o granito, onde é paralela ao mesmo O valor global da susceptibilidade magnética das rochas ígneas do maciço de Sintra varia significativamente entre as fácies gabróicas (K: 72080 x 10-6 S.I.), que afloram na região mais a oeste do maciço, e as fácies sieníticas e graníticas envolventes (K: 39 x 10-6 S.I.). A intrusão do lacólito de Sintra ocorreu no Cretácico superior e foi controlada por dois conjuntos de falhas: um, de orientação NNW-SSE/90º, profundo, controlando a ascenção magmática inicial através da litosfera mais profunda e apenas localmente rompendo á superfície e, outro, de orientação WNW-ESE, controlando a instalação final do maciço. Durante o Terciário (muito provavelmente o Miocénico) o maciço de Sintra foi exumado e atingiu a sua altitude actual, devido á formação de um cavalgamento, vergente para norte, com uma direcção E-W aproximada, observável no contacto norte das rochas ígneas do maciço de Sintra com as rochas do encaixante sedimentar. Estima-se em 2 km a movimentação total no plano de cavalgamento. publishersversion published

The existence of satellite images ofthe West Iberian Margin allowed comparative study of images as a tool applied to structural geology. Interpretation of LANDSAT images of the Lusitanian Basin domain showed the existence of a not previously described WNW-ESE trending set oflineaments. These lineaments are persistent and only observable on small scale images (e.g. approx. 11200000 and 11500 000) with various radiometric characteristics. They are approximately 20 km long, trend l200±15° and cross cut any other families oflineaments. The fact that these lineaments are perpendicular to the Quaternary thrusts of the Lower Tagus Valley and also because they show no off-set across them, suggests that they resulted from intersection oflarge tensile fractures on the earth's surface. It is proposed in this work that these lineaments formed on a crustal flexure of tens ofkm long, associated with the Quaternary WNW-ESE oriented maximum compressive stress on the West Iberian Margin. The maximum compressive stress rotated anticlockwise from a NW -SE orientation to approximately WNW-ESE, from Late Miocene to Quaternary times (RIBEIRO et aI., 1996). Field inspection of the lineaments revealed zones of norm~1.J. faulting and cataclasis, which are coincident with the lineaments and affect sediments of upper Miocene up to Quaternary age. These deformation structures show localized extension perpendicular to the lineaments, i.e. perpendicular to the maximum compressive direction, after recent stress data along the West Portuguese Margin (CABRAL & RIBEIRO, 1989; RIBEIRO et at., 1996). Also, on a first approach, the geographical distribution of these lineaments correlates well with earthquake epicenters and areas of largest Quaternary Vertical Movements within the inverted Lusitanian Basin (CABRAL, 1995).

The marginal zones of the Maestrazgo Basin (Las Parras and Galve basins) and the Algarve Basin show a similar evolution during basin formation (mainly Jurassic and Early Cretaceous) and inversion (Oligocene-Early Miocene). Common features between the two basins are the control of sedimentation during extension by basement normal and transfer faults (NW-SE and NE-SW) and the complete inversion during the Tertiary accomodated by basement-involved E-W thrusts, preserving the extensional geometry with non-reactivated normal faults at the thrusts hanging-walls. Extensional structures in the Las Parras and Calve basins are consistent with a roughly N-S oriented extension (locally NE-SW and NW-SE, perpendicular to the main normal faults). Thrusts show an overall E-W direction compatible with a near N-S shortening between the Late Eocene and the Early Miocene. Extension in the Algarve Basin was accomodated by ENE-WSW to NE-SW late Variscan faults; NW-SE transfer faults dipping to the Northeast also accomodated some extension and divided the area into sub-basins. Inversion in the Algarve Basin pre-dated deposition ofthe Miocene sediments and was accomodated by S- to S-SE directed thrusts, which cross-cut the main extensional faults

The marginal zones of the Maestrazgo Basin (Las Parras and Galve basins) and the Algarve Basin show a similar evolution during basin formation (mainly Jurassic and Early Cretaceous) and inversion (Oligocene-Early Miocene). Common features between the two basins are the control of sedimentation during extension by basement normal and transfer faults (NW-SE and NE-SW) and the complete inversion during the Tertiary accomodated by basement-involved E-W thrusts, preserving the extensional geometry with non-reactivated normal faults at the thrusts hanging-walls. Extensional structures in the Las Parras and Calve basins are consistent with a roughly N-S oriented extension (locally NE-SW and NW-SE, perpendicular to the main normal faults). Thrusts show an overall E-W direction compatible with a near N-S shortening between the Late Eocene and the Early Miocene. Extension in the Algarve Basin was accomodated by ENE-WSW to NE-SW late Variscan faults; NW-SE transfer faults dipping to the Northeast also accomodated some extension and divided the area into sub-basins. Inversion in the Algarve Basin pre-dated deposition ofthe Miocene sediments and was accomodated by S- to S-SE directed thrusts, which cross-cut the main extensional faults

N.º4, p.263-267 The Arrábida chain - located in the southern segment of the Lusitanian basin - is a S-wards directed fold and thrust belt of Miocene age of deformation. ENE-WSW striking frontal ramps and associated folds are connected to sinistral NNE-SSW and N-S striking lateral ramps, that show left-lateral and SE-wards reverse movements. Both frontal and oblique ramps form imbricate duplexes. Constriction increases SE-wards due to the presence of a basin boundary fault (SetúbaI- Pinhal Novo fault) that acts as a buttress to the oblique thrust movement. Kilometre scale transpressive structures can be observed along the basin boundary fault. A map scale sheath fold like structure can be observed at the Viso anticline, which is a consequence of a strong anisotropy contrast of the Mesocenozoic strata.The Arrábida chain thrusts migrated backward, i.e. to the north, according to an overstep model. Detailed geometrical reconstruction and kinematic analysis of the structures of the eastern region of Arrábida (Formosinho, Vise and Serra de S. Luis anticlines) show that a thin-skinned tectonic model (Ribeiro, A. et aI., 1990) fits very well with the geometry of the structures of the Arrábida chain.

The development of an algorithm for the construction of auxiliary projection nets (conform, equivalent and orthographic), in the equatorial and polar versions, is presented. The algorithm for the drawing of the "IGAREA 220" counting net (ALYES & MENDES, 1972), is also presented. Those algorithms are the base of STEGRAPH program (vers. 2.0), for MS-DOS computers, which has other applications.

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Since the XIX century, Portuguese and foreign geologists have defined 47 new invertebrate taxa (foraminifera, ostracods, coelenterates, brachiopods, gastropods, ammonoids, echinoids), 2 new fossil plant taxa (charophyte and pteridophyte) and 1 ichnofossil, using toponymy from the Algarve; these taxa refer to 1 genera, 47 species and 2 varieties. Besides the Algarve toponym, the most used as specific name, twenty others have been used, mostly from western Algarve; these toponyms are associated to: – Miocene units, particularly from Ribeira de Cacela and Ferragudo; – Cretaceous units between Zavial and Marim; – Upper Jurassic units from Sagres, Carrapateira and Loulé and Middle Jurassic units from Sagres and Guilhim; – Triassic units from Vila do Bispo to Tavira; – Carboniferous units, particularly from the Aljezur-Bordeira-Carrapateira region. The earliest of these designations were attributed to seven gastropods from the Upper Miocene of Cacela (COSTA, 1866-1867). The majority of the named species are typical of the Algarve, but some have been collected, as well, in the Lusitanian Basin. Although extensively cited in the geological literature, some of these taxa either do not fulfill the ICZN rules, or fall into synonymy with previously established taxa, or should be formally considered as non valid names (nomem nudum and nomen oblitum). Only widespread bibliographical review, associated with the palaeontological revision of some of these groups and the correct interpretation of the ICZN articles, will allow confirming, or not, the doubts that have now arisen.

e-Terra - Revista Electrónica de Ciências da Terra ISSN 1645-0388, Volume 15 – nº 10 2010 É apresentado o panorama actual, nacional e internacional, sobre o Acesso Livre ao conhecimento científico através da Web. São apresentadas estatísticas que demonstram os benefícios e a utilidade desta nova forma de divulgação do conhecimento, não apenas pelo incremento das citações, mas também pela formação dos jovens investigadores e, mesmo do ponto de vista ético. São também apresentadas estatísticas sobre as publicações periódicas de Geologia em Portugal, sobre as quais se conclui também pela necessidade da constituição de um repositório bibliográfico digital.

RESUMO: Desde o século XIX foram definidas sete novas espécies de três invertebrados, dois microfósseis e de dois vegetais fósseis, utilizando o topónimo Tejo. Apesar de pouco citados na bibliografia geológica, eles cumprem, na generalidade, as regras do International Code of Zoological Nomenclature (ICZN) e do International Code of Botanical Nomenclature (ICBN), e são considerados, formalmente, como nomes válidos. ABSTRACT: Since the nineteenth century seven new species of three invertebrates, two microfossils and two fossil plants were defined using the toponym of the Tagus River. Although not much cited in the geological literature, the names of these taxa comply, in general, with the rules of the International Code of Zoological Nomenclature (ICZN) and the International Code of Botanical Nomenclature (ICBN) and must be formally considered as valid names. info:eu-repo/semantics/publishedVersion