Spatial variability of seabird distribution associated with environmental factors: a case study of marine Important Bird Areas in the Azores     

Amorim  Patricia; Figueiredo  Miguel; Machete  Miguel; Morato  Telmo; Martins  Ana; Serrao Santos  Ricardo 《ICES Journal of Marine Science》2009,66(1):29-40

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The 1909 Benavente (Portugal) earthquake: search for the source   总被引：1，自引：0，他引：1  

J. Cabral  C. Moniz  J. Batlló  P. Figueiredo  J. Carvalho  L. Matias  P. Teves-Costa  R. Dias  N. Simão 《Natural Hazards》2013,69(2):1211-1227

The Lower Tagus River Valley has been affected by severe earthquakes comprising distant events, as in 1755, and local earthquakes, as in 1344, 1531, and 1909. The 1909 earthquake was located NE of Lisbon, near Benavente, causing serious damage and many losses. Mw 6.0 has been assessed for this earthquake and a reverse faulting focal mechanism solution has been calculated. Poor epicenter location, possible directivity and site effects, low fault slip rates, and the thick Cenozoic sedimentary cover make difficult correlation with regional structures. The focal mechanism indicates an ENE reverse fault as source, though it does not match any outcropping active structure suggesting that the event could have been produced by a blind thrust beneath the Cenozoic sedimentary fill. Hidden sources, inferred from seismic reflection data, are a possible NE structure linking the Vila Franca de Xira and the Azambuja faults, or the southern extension of the later. Evidence of surface rupturing is inhibited by the thick Holocene alluvial cover and the high fluvial sedimentation rate, though a slightly depressed area was identified in the Tagus alluvial plain W of Benavente which was investigated as possible geomorphic evidence of co-seismic surface deformation. A high-resolution seismic reflection profile was acquired across a 0.5 m high scarp at this site, and two trenches were opened across the scarp for paleoseismic research. Some deformation of dubious tectonic origin was found, requiring further studies.  相似文献   

The Rio Capim volcanic–plutonic–sedimentary belt,São Francisco Craton,Brazil: Geological,geochemical and isotopic evidence for oceanic arc accretion during Palaeoproterozoic continental collision     

E.P. Oliveira  Z.S. Souza  N.J. McNaughton  J.-M. Lafon  F.G. Costa  A.M. Figueiredo 《Gondwana Research》2011,19(3):735-750

The collision of oceanic arcs with continents is a common plate tectonic process in the Phanerozoic, but its recognition in the Precambrian is hampered by deformation and metamorphism. The Rio Capim volcanic–plutonic–sedimentary belt lies in sharp tectonic contact with Archaean rocks of the Uauá block in the northern part of the São Francisco craton. Field relationships and high-precision geochronology indicated that the Rio Capim basalts, gabbros, diorites, and dacites were emplaced approximately at 2148–2143 Ma, and later intruded by 2128 Ma-old diorite to tonalite plutons. All rocks were metamorphosed under amphibolite to granulite facies conditions mainly between 2080 Ma and 2070 Ma, but deformation may have lasted until about 2040 Ma as estimated from syn-deformation zircon and titanite grains. The association of basalt, andesite, dacite, and their plutonic counterparts, combined with their positive ε_Nd(t) values and incompatible trace element geochemical signatures similar to island arc magmas, support the proposition that the Rio Capim belt was a Palaeoproteorozoic intra-oceanic arc sequence that collided with a continent, of which the Mesoarchaean Uauá block is a remnant. The implications for the regional evolution and metallogenesis are also discussed.  相似文献   

Limestones under salt decay tests: assessment of pore network-dependent durability predictors     

Carlos Alves  Carlos Figueiredo  António Maurício  Maria Amália Sequeira Braga  Luís Aires-Barros 《Environmental Earth Sciences》2011,63(7-8):1511-1527

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Angular power spectrum of the fastica cosmic microwave background component from Background Emission Anisotropy Scanning Telescope data     

S. Donzelli  D. Maino  M. Bersanelli  J. Childers  N. Figueiredo  P. M. Lubin  P. R.  Meinhold  I. J. O'Dwyer  M. D. Seiffert  T. Villela  B. D. Wandelt  C. A. Wuensche 《Monthly notices of the Royal Astronomical Society》2006,369(1):441-448

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Special issue on oceanic seismic exploration--Introduction to the issue     

De Figueiredo  R. Gardner  G. 《Oceanic Engineering, IEEE Journal of》1984,9(1):1-2

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Special publications around the world mark the International Year of Planet Earth     

I. J. Graham  B. R. Figueiredo  L. Hidalgo Nunes 《Environmental Geology》2008,54(4):893-894

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Tectonic activation,source area stratigraphy and provenance changes in a rift basin: the Early Cretaceous Tucano Basin (NE‐Brazil)          下载免费PDF全文

Felipe T. Figueiredo  Renato P. Almeida  Bernardo T. Freitas  Andre Marconato  Simone C. Carrera  Bruno B. Turra 《Basin Research》2016,28(4):433-445

Changes in sandstone and conglomerate maturity in tectonically active basins can be considered either as the product of climatic change or of tectonic restructuring of the feeder drainage system. Besides these regional controls, changes in the configuration of local sources can expressively affect basin fill composition. The Early Cretaceous fluvial successions of the Tucano Basin, a rift basin in northeastern Brazil related to the South Atlantic opening, contain one such case of abrupt change in maturity, marked by the passage from pebbly sandstone and conglomerate rich in quartz and quartzite fragments (Neocomian to Barremian São Sebastião Formation) to more feldspathic pebbly sandstone and conglomerate bearing pebbles of varied composition (Aptian Marizal Formation). Systematic analysis of stratigraphic and spatial variation in palaeocurrents and composition of pebbles and cobbles from both units, integrated with the recognition of fluvial and alluvial fan deposits distribution, revealed an abrupt decrease in maturity during the passage from the São Sebastião Formation to the Marizal Formation. This change is explained by exhumation of basement rocks and erosional removal of originally widespread Silurian to Jurassic sandstone and conglomerate units which were a major source of reworked vein quartz and quartzite pebbles to the São Sebastião Formation. Basin border faults activation during the deposition of the Marizal Formation caused adjacent basement uplift above the local erosional base level at the basin borders, whereas during the São Sebastião Formation deposition, the basin border fault scarps probably exposed mineralogically mature sedimentary units. The proposed model has important implications for interpreting changes in sediment maturity in rift basin successions, as similar results are expected where activation of basin border faults occurs after the erosional removal of older sedimentary or volcanic units that controlled syn‐rift successions composition.  相似文献   

Platinum-Group Elements and Gold Determination in NiS Fire Assay Buttons by UV Laser Ablation ICP-MS     

Alexandre P.de S. Jorge  Jacinta Enzweiler  Elisa K. Shibuya  Jorge E.S. Sarkis  Ana Maria G. Figueiredo 《Geostandards and Geoanalytical Research》1998,22(1):47-55

The direct analysis of nickel sulfide fire assay buttons by UV laser ablation ICP-MS was used to determine the platinum-group elements and gold in the following reference materials: UMT-1, WPR-1, WMG-1, GPt-4, GPt-6 and CHR-Bkg. The instrument was calibrated with buttons prepared using quartz doped with the appropriate standard solutions. Analytical precision (RSD) was generally better than 10%, although occasional higher RSDs may infer local heterogeneities within nickel sulfide buttons. Good or excellent agreement was observed between analysed and reference material values except Rh in UMT-1 and WMG-1, which suffered an interference from copper. Detection limits calculated as 10 s quantitation limits were Au (1.7 ng g⁻¹), Pd (3.3 ng g⁻¹), Pt (8.3 ng g⁻¹), Os (1.3 ng g⁻¹), Rh (1 ng g⁻¹), Ru (5 ng g⁻¹) and Ir (0.7 ng g⁻¹).  相似文献   

Observations on the reproductive cycle of the black scabbardfish (Aphanopus carbo Lowe, 1839) in the NE Atlantic     

Figueiredo  I; Bordalo-Machado  P; Reis  S; Sena-Carvalho  D; Blasdale  T; Newton  A; Gordo  L.S 《ICES Journal of Marine Science》2003,60(4):774-779

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