Browsing by Author "Rosa, Diogo"
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- Carboniferous palynostratigraphy of the borehole SDJ1 from the Santa Susana region, Ossa Morena Zone, PortugalPublication . Pereira, Zélia; Lopes, Gilda; Fernandes, Paulo; Matos, João Xavier; Rosa, Diogo; Oliveira, José TomásThe borehole SDJ1, with a total depth of 404.5 meters, was drilled in 1991 by the Serviço de Fomento Mineiro to investigate an Electromagnetic TEM conductor (Oliveira & Matos 1991). This hole is located in the eastern sector of the Santa Susana/Moinho da Ordem coal mine (1927-1944), in the Jongeis mine sector. The borehole log indicates that it cuts lithologies of the Carboniferous Toca da Moura Complex (TMC) and the Santa Susana Formation (SSF).
- Contribuição para o estudo da estrutura da mina de Aljustrel (Faixa Piritosa Ibérica) com base em novos dados palinoestratigráficos do Complexo Vulcano-Sedimentar e da Fm. MértolaPublication . Matos, João Xavier; Pereira, Zélia; Fernandes, Paulo; Rosa, Diogo; Oliveira, José TomásA cartografia geológica de detalhe e a análise palinoestratigráfica de sedimentos do Complexo Vulcano-Sedimentar da Faixa Piritosa e da Fm. Mértola, na região da mina de Aljustrel, permite uma melhor compreensão da estrutura local. A Fm. Paraíso apresenta uma idade Tournaisiano sup. - Viseano inf. (biozonas CM e Pu). A Fm. Gavião tem uma idade semelhante, contendo associações de miosporos da biozona CM, do Tournaisiano sup. Propõe-se uma nova unidade sedimentar correspdente à base da Fm. Mértola, a Unidade Canal da BAI, de idade Viseano médio-sup. (biozona NM).
- Geologia Sul Portuguesa, com ênfase na estratigrafia, vulcanologia física, geoquímica e mineralizações da faixa piritosaPublication . Oliveira, José Tomás; Relvas, J.; Pereira, Zélia; Munhá, José; Rosa, Carlos; Rosa, Diogo; Fernandes, Paulo; Jorge, R. C. G. S.; Pinto, ÁlvaroO presente trabalho resulta da adaptação e actualização do artigo «O Complexo Vulcano--Sedimentar da Faixa Piritosa: Estratigrafia, Vulcanismo e Mineralizações Associadas no Contexto da Zona Sul Portuguesa» de autoria de Oliveira et al., inserido no Livro Geologia de Portugal no Contexto da Ibéria, editado por Rui Dias, Alexandre Araújo, Pedro Terrinha e Carlos Kulberg e publicado pela Universidade de Évora, em 2006, durante o VII Congresso Nacional de Geologia.
- A importância dos palinomorfos remobilizados no Complexo Vulcano-Sedimentar da Toca da Moura - Implicações para a evolução geodinâmica da Zona de Ossa Morena, PortugalPublication . Lopes, Gilda; Pereira, Zélia; Fernandes, Paulo; Wicander, Reed; Matos, João Xavier; Rosa, Diogo; Oliveira, José TomásO estudo palinostratigráfico da sondagem SDJ11 permitiu a recuperação de associações in situ de palinomorfos do Carbónico assim como associações de palinomorfos remobilizados do Câmbrico médio ao Devónico inferior e Câmbrico médio ao Tournaisiano.
- Provenance of the reworked Ordovician Palynomorphs in SDJ1 Borehole - Santa Susana Basin, Ossa Morena Zone, PortugalPublication . Lopes, Gilda; Pereira, Zélia; Fernandes, Paulo; Matos, João Xavier; Rosa, Diogo; Oliveira, José TomásThe detail palynological study of the exploration borehole SDJ1 located in the Santa Susana / Moinho da Ordem disused coal mine area (1927‐1944), western border of the Ossa Morena Zone (OMZ) in Portugal, is presented here. The borehole intersects lithologies of the Toca da Moura Complex (TMC) and the Santa Susana Formation (SSF), dated as mid late Viséan and Moscovian (Carboniferous), respectively, based on palynomorphs (Cunha in Andrade et al., 1991; Pereira et al., 2006; Machado, 2010; Pereira et al., 2011) and macroflora (Wagner & Sousa, 1983). Together with the miospore associations recovered, assemblages of exceptional well‐ preserved Lower Palaeozoic acritarchs, cryptospores and spores were identified, which are interpreted asreworked. From these, the major percentage is Ordovician acritarchs. The ages of the reworked palynomorphs suggest that considerable erosion of exposed Lower Palaeozoic OMZ basement occurred during early Carboniferous times. The exposure of these rocks may have occurred by the first phases of the Variscan Orogeny in the OMZ. In this work the acritarch assemblages recovered from the SDJ1 borehole are compared with the acritarch assemblage identified from the Phyllodocites Shales Formation (Cunha & Vanguestaine, 1988; Pereira et al, 2011) in Barrancos region. Due to the resemblance in the acritarchs assemblages of both places we suggest that the Early Ordovician Phyllodocites Shales and correlatives were one of the main sources of the reworked acritarchs (Piçarra et al., 2011).
- The geodynamic importance of the Late Cambrian to Late Devonian reworked palynomorphs from the borehole SDJ1, Santa Susana region, Ossa Morena Zone (OMZ), PortugalPublication . Lopes, Gilda; Pereira, Zélia; Fernandes, Paulo; Matos, João Xavier; Rosa, Diogo; Oliveira, José TomásThe detail study of the borehole SDJ1 from the Santa Susana coal basin western border of the OMZ, Portugal, proved that most of the volcano sedimentary lithologic sequence yielded palynomorphs of mid late Visean age (NM Biozone) i.e., they belong to the Toea da Moura Volcano Sedimentary Complex (TMC). The deepest few meters of the drill core have shales of mid Moscovian (Biozona SL) (see Pereira et ai., in this volume).Together with the miospore assemblages that provide the age of the SDJ1 strata, mid late Visean and Moscovian age, associations of exceptional well preserved Lower Palaeozoic acritarchs and spores were identified and interpreted as reworked into the Carboniferous ocks. Four ages of reworked associations were identified: 1 - Late Cambrian acritarchs: Aeanthodiaerodium ?petrovii, Cristallinium randomense, Eliasum sp., Timofeevia phosphoritica; 2 - Ordovician acritarchs: Navifusa punctata, Stelliferidium striatulum, Striatotheea rarirrugulata; 3 - Mid Late Silurian to Lower Devonian, spore taxa: Ambitisporites sp., Arehaeozonotriletes ehulus, Brochotriletes sp., Dietyotriletes subgranifer; Emphanisporites sp. and Synorisporites Jabeonis, cryptospores taxa aevolaneis sp., Tetrahedraletes medinensis and Quadritisporites variabilis, acritarch taxa such as Ouvernaysphaera aranaides, Micrhystridium stellatum, Multiplicisphaeridium ramusculosum; 4 - Late Devonian miospore taxa: Retispora lepidophyta and Rugospora f1exuosa and acritarch taxa Craterosphaeridium ?sprueegrovense, Gorgonisphaeridium ohioense, Stellinium eomptum, S. mieropolygonale, Vil/osaeapsula eolemanii, Pterospermella sp.. Detail examination of the reworked assemblages, still in progress, indicates that these are clearly dominated by Late Cambrian, Early Ordovician and Late Devonian acritarchs. In minor amount are Mid Silurian to Lower Devonian palynomorphs and the typical Middle Devonian species are very scarce. The TMC sediments are interpreted as had been deposited in an intra-arc basin in close association with the igneous rocks of the Beja Massif, a magmatic arc installed at the south border of the OMZ (Oliveira et al. 2006). The ages of the reworked palynomorphs suggest that considerable erosion of exposed Lower Palaeozoic OMZ basement occurred during Carboniferous times. The exposure of these rocks may have occurred during the first phases of the Variscan Orogeny in the OMZ. Within the OMZ the rock formations that may constitute the sources for the reworked palynomorphs are: the Early Ordovician Phyllodoeites Shales (Pigarra et aI., 2011); the Raiados and Nodulos Shales Fm. and the Terena Fm. of Mid ate Silurian to Early Devonian, age (Pereira et aL, 1999; Lopes et ai., 2009). The Late Devonian association could have come from the South Portuguese Zone, where late amennian palynomorphs are very well documented. Lastly, there are no units of proven late Cambrian age in the OMZ. The occurrence of reworked Late Cambrian palynomorphs in the Santa Susana region indicates that elsewhere in the OMZ, sedimentation of this age must have existed.
- The significance of reworked palynomorphs (middle Cambrian to Tournaisian) in the Visean Toca da Moura Complex (South Portugal). Implications for the geodynamic evolution of Ossa Morena ZonePublication . Lopes, Gilda; Pereira, Zélia; Fernandes, Paulo; Wicander, Reed; Matos, João Xavier; Rosa, Diogo; Oliveira, José TomásThe 404.5 m deep SDJ1 borehole is located in the Jongeis mining sector of the Santa Susana Basin (SSB), and has been palynostratigraphically studied. The SSB is a Carboniferous coal-bearing basin developed along the suture contact between the Ossa Morena Zone (OMZ) and the South Portuguese Zone (SPZ).