Carlos Grangeia | University of Aveiro (original) (raw)

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Papers by Carlos Grangeia

Construction and Building Materials, 2014

VIII CNG 2010, Jun 25, 2010

Com o intuito de estudar a estrutura interna das dunas costeiras localizadas a sul da Nazaré, apl... more Com o intuito de estudar a estrutura interna das dunas costeiras localizadas a sul da Nazaré, aplicou-se o método GPR ao longo de um perfil transversal adquirido sobre as dunas estabilizadas ea duna frontal. No radargrama obtido é possível observar-se reflectores com diferentes amplitudes, continuidade, direcções e inclinações, cuja intercepção permitiu identificar quatro fases evolutivas principais neste complexo dunar, que se desenvolveu no tempo por progradação de leste para oeste.

Ao longo do tempo o património edificado deteriora-se devido a causas naturais ou antrópicas. A a... more Ao longo do tempo o património edificado deteriora-se devido a causas naturais ou antrópicas. A acção sísmica é um factor que pode provocar danos estruturais nas paredes das construções tradicionais, por vezes até imperceptíveis à vista desarmada. A Geofísica aplicada proporciona técnicas de elevada resolução que permitem detectar alvos de pequenas dimensões, como por exemplo fendas na estrutura interna de paredes. O georadar, técnica não invasiva, utiliza impulsos electromagnéticos de frequências ...

Abstract—The internal structure of costal dunes located south of Nazaré was analyzed using Ground... more Abstract—The internal structure of costal dunes located south of Nazaré was analyzed using Ground Penetrating Radar. These coastal dunes comprise stabilized dunes, located in the inner part of the dune field, and foredunes, both separated by a dry dune slack. The radargram analysis allowed the identification of five bounding surfaces that define six main aeolian sand units. The Units I, II, III and IV correspond to the progradation of foredunes seaward (NW), while Units V and VI represent the migration of a parabolic dune and a blowout, respectively, to southeast. A strong reflector separating Units I, II and III from Unit V is interpreted as a paleosoil, suggesting a break in aeolian sedimentation of unknown duration, but with sufficient time for soil development. The absent of the paleosoil over the Unit IV leave some doubts in relation to its relative age, although is indicative of the occurrence of an erosive event. Radar stratigraphic analysis provided a relative chronology of ...

GPR techniques are fast, non destructive and non invasive that allow high resolution shallow subs... more GPR techniques are fast, non destructive and non invasive that allow high resolution shallow subsoil investigations. Archaeological surveys can beneficiate from these techniques since they provide high resolution bidimensional and tridimensional results of the survey area which are not given by other geophysical techniques (magnetic and electrical resistivity). Here it is presented and discussed the application and the interpretation of field GPR data, that is two case studies. The first in a karsified landscape environment for cavity location in Anca (near Coimbra) and the other over roman remains in S. Martinho de Arvore (near Coimbra). 1. Introducao

The risks associated with mine tailings have different nature and, thus, only a multiple approach... more The risks associated with mine tailings have different nature and, thus, only a multiple approach can investigate and monitor comprehensively the characteristics and evolution of mine tailings impacts on the environment. Deposition at the Rio tailings (Panasqueira Mine) lasted about ninety years. Over one million cubic metres, of complex very fine to fine material, are deposited on a mountain side overlaying the Zezere river, increasing the risk of contamination of one of the most important hydrographic basins in central Portugal. Herein, a multidisciplinary study including geophysics, geochemistry and borehole information, organized in a GIS, is used to characterize the Rio tailings. The geophysical survey comprised ERT (Electrical Resistivity Tomography) and GPR (Ground Penetrating Radar) on the mud impoundment, as well as, on the slope of the tailings. The geochemical survey consisted on collecting water and tailings samples, iron coatings, arsenopyrite stockpile material and fer...

63rd EAGE Conference & Exhibition

64th EAGE Conference & Exhibition

9th EAGE/EEGS Meeting, 2003

Specific conductance is given in microsiemens per centimeter at 25 degrees Celsius (μS/cm at 25°C... more Specific conductance is given in microsiemens per centimeter at 25 degrees Celsius (μS/cm at 25°C). Concentrations of chemical constituents in water are given in either milligrams per liter (mg/L) or micrograms per liter (μg/L). Conversion Factors a future annual 325 acre-feet of discharge is derived from depletion of streamflow in the West Channel of the Uinta River. A similar result was observed in a predictive model simulating the same discharge rate but with the new well being pumped every other year.

Construction and Building Materials, 2014

VIII CNG 2010, Jun 25, 2010

Com o intuito de estudar a estrutura interna das dunas costeiras localizadas a sul da Nazaré, apl... more Com o intuito de estudar a estrutura interna das dunas costeiras localizadas a sul da Nazaré, aplicou-se o método GPR ao longo de um perfil transversal adquirido sobre as dunas estabilizadas ea duna frontal. No radargrama obtido é possível observar-se reflectores com diferentes amplitudes, continuidade, direcções e inclinações, cuja intercepção permitiu identificar quatro fases evolutivas principais neste complexo dunar, que se desenvolveu no tempo por progradação de leste para oeste.

Ao longo do tempo o património edificado deteriora-se devido a causas naturais ou antrópicas. A a... more Ao longo do tempo o património edificado deteriora-se devido a causas naturais ou antrópicas. A acção sísmica é um factor que pode provocar danos estruturais nas paredes das construções tradicionais, por vezes até imperceptíveis à vista desarmada. A Geofísica aplicada proporciona técnicas de elevada resolução que permitem detectar alvos de pequenas dimensões, como por exemplo fendas na estrutura interna de paredes. O georadar, técnica não invasiva, utiliza impulsos electromagnéticos de frequências ...

Abstract—The internal structure of costal dunes located south of Nazaré was analyzed using Ground... more Abstract—The internal structure of costal dunes located south of Nazaré was analyzed using Ground Penetrating Radar. These coastal dunes comprise stabilized dunes, located in the inner part of the dune field, and foredunes, both separated by a dry dune slack. The radargram analysis allowed the identification of five bounding surfaces that define six main aeolian sand units. The Units I, II, III and IV correspond to the progradation of foredunes seaward (NW), while Units V and VI represent the migration of a parabolic dune and a blowout, respectively, to southeast. A strong reflector separating Units I, II and III from Unit V is interpreted as a paleosoil, suggesting a break in aeolian sedimentation of unknown duration, but with sufficient time for soil development. The absent of the paleosoil over the Unit IV leave some doubts in relation to its relative age, although is indicative of the occurrence of an erosive event. Radar stratigraphic analysis provided a relative chronology of ...

GPR techniques are fast, non destructive and non invasive that allow high resolution shallow subs... more GPR techniques are fast, non destructive and non invasive that allow high resolution shallow subsoil investigations. Archaeological surveys can beneficiate from these techniques since they provide high resolution bidimensional and tridimensional results of the survey area which are not given by other geophysical techniques (magnetic and electrical resistivity). Here it is presented and discussed the application and the interpretation of field GPR data, that is two case studies. The first in a karsified landscape environment for cavity location in Anca (near Coimbra) and the other over roman remains in S. Martinho de Arvore (near Coimbra). 1. Introducao

The risks associated with mine tailings have different nature and, thus, only a multiple approach... more The risks associated with mine tailings have different nature and, thus, only a multiple approach can investigate and monitor comprehensively the characteristics and evolution of mine tailings impacts on the environment. Deposition at the Rio tailings (Panasqueira Mine) lasted about ninety years. Over one million cubic metres, of complex very fine to fine material, are deposited on a mountain side overlaying the Zezere river, increasing the risk of contamination of one of the most important hydrographic basins in central Portugal. Herein, a multidisciplinary study including geophysics, geochemistry and borehole information, organized in a GIS, is used to characterize the Rio tailings. The geophysical survey comprised ERT (Electrical Resistivity Tomography) and GPR (Ground Penetrating Radar) on the mud impoundment, as well as, on the slope of the tailings. The geochemical survey consisted on collecting water and tailings samples, iron coatings, arsenopyrite stockpile material and fer...

63rd EAGE Conference & Exhibition

64th EAGE Conference & Exhibition

9th EAGE/EEGS Meeting, 2003

Specific conductance is given in microsiemens per centimeter at 25 degrees Celsius (μS/cm at 25°C... more Specific conductance is given in microsiemens per centimeter at 25 degrees Celsius (μS/cm at 25°C). Concentrations of chemical constituents in water are given in either milligrams per liter (mg/L) or micrograms per liter (μg/L). Conversion Factors a future annual 325 acre-feet of discharge is derived from depletion of streamflow in the West Channel of the Uinta River. A similar result was observed in a predictive model simulating the same discharge rate but with the new well being pumped every other year.