Navegando por Assunto "Radar de penetração no solo"

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Acesso aberto (Open Access)
Análise de feições geológicas na região de Tartarugalzinho, Amapá, através de métodos geofísicos
(Universidade Federal do Pará, 2009) MARTINS, Saulo Siqueira; PINHEIRO, Roberto Vizeu Lima; http://lattes.cnpq.br/3251836412904734; LUIZ, José Gouvêa; http://lattes.cnpq.br/8676530374310847
Two geophysical methods were applied to detect geologic structures on the oriental edge of the Guianas Shield. The gravimetric method was applied mainly to find faulting on the basement, associated to shear belts that have orientation NW-SE. It was found faulting on the basement as well as an indication that the crust suffered a thinning in some region of the edge. The GPR electromagnetic method was applied to find geologic discontinuities on the sediments and to check if they are reflex of structural faults on the basement and/or reactivation of some of them. The GPR showed places where discontinues and some paleostructures can be observed. The study was also applied to understand how the basement discontinuities can influence on the formation of Tertiary sedimentary basins and on the formation of shallow paleostructures.
Acesso aberto (Open Access)
Estratigrafia da sucessão sedimentar Pós-Barreiras (Zona Bragantina, Pará) com base em radar de penetração no solo
(2001-08) ROSSETTI, Dilce de Fátima; GÓES, Ana Maria; SOUZA, Lena Simone Barata
Ground penetrating radar (GPR) is a geophysical method that consists in the emission of electromagnetic waves of high frequency (between 10-2500 Mhz). This equipment has been increasingly applied for mapping of physical properties and chemical compositions of rocks at shallow depth, as well as for stratigraphic and facies analysis. The application of this methodology in Brazil is still reduced to a few studies, mostly emphasizing soil stratigraphy and eolian paleoenvironments. However, previous studies undertaken in northern Brazil have demonstrated that, in combination with traditional studies using outcrop data, the GPR might be a powerful additional tool to help correlating sedimentary successions and reconstruct depositional environments throughout the Neogene in the Bragantina Zone. In this paper, we will document a pioneer investigation applying a SYR-2 GPR system (Geophysical Survey Systems Inc.) in the Praia do Atalaia area, Salinópolis, northern Brazil, which allowed us to characterize, for the first time, facies and stratigraphy of the deposits known informally as Pós-Barreiras Sediments (Pliocene and younger). The equipment was operated using a 200 Mhz monostatic antenna in continuous mode. The acquired sections were processed using the RADANWIN software in order to increase the reflection resolution and thus allow a refined interpretation of the sections. Based on this procedure, it was noticed that the studied sedimentary succession overlies unconformably the Miocene basement, represented by the Pirabas/Barreiras formations. Three stratigraphic units were also distinguished. The lowermost Unit 1 consists of an interval up to 6 m thick dominated by poorly-defined, low amplitude reflections, which intergrade with medium-scale, tangential oblique and hummocky reflections. This unit revealed to be discontinuous throughout the studied radar sections, occurring mainly where the Miocene basement is depressed. The middle Unit 2 is circa 9 m thick and mostly includes large-scale oblique reflections varying in style from parallel, tangential, sigmoidal to sigmoidal complex. The two latter ones might reach up to 7 m thick. A strong, high amplitude and laterally continuous reflection marks the top of Unit 2, forming a bounding surface having local depressions of up to 40 m in relief. The uppermost Unit 3 corresponds to an interval ranging from 3.5 to 9 m thick, which is dominated by hummocky reflections, followed by medium-scale oblique, parallel to sub-parallel and cut and fill reflections. The GPR data allows the interpretation that the Pós-Barreiras Sediments were unconformably deposited over the Miocene deposits, as revealed by the mapping of an erosional bounding surface at the base of Unit 1. In addition, the analysis of internal reflection configurations and reflection geometries led us to propose that the Pós-Barreiras Sediments is more variable in terms of facies than previously thought, including eolian deposits (coastal dunes), as well as beach ridge, tidal flat, channel and mangrove deposits. Furthermore, the mapping of the three stratigraphic units described above is important to unravel the complexity of sedimentation versus erosion during the latest Neogene in northern Brazil. The conclusions obtained from the GPR data lead to suggest a drop in relative sea level after the end of the Miocenelower Pliocene in the Bragantina Zone, which was followed by a transgression and deposition of Unit 1 along embayments and adjacent eolian dunes and/or beach ridges. Renewed phase of relative sea level drop took place, which led to erosion of the uppermost portions of Unit 1, forming a bounding surface that is locally cut by fluvial channel scouring. Large-scale eolian dunes laterally intergraded with tidal flat, filling the depressions formed by channel erosion during a subsequent transgressive phase. At least one more drop in relative sea level appears to have taken place in the study area, as revealed by the discontinuity surface between units 2 and 3, which is in turn mantled by modern sedimentation along mangroves, tidal channels and coastal dune environments.
Acesso aberto (Open Access)
Estudo da contaminação por hidrocarbonetos em postos de serviços de Abaetetuba-PA utilizando georadar
(Universidade Federal do Pará, 2007) ALMEIDA, Fabíola Magalhães de; LUIZ, José Gouvêa; http://lattes.cnpq.br/8676530374310847
The work presents the results of a geophysical survey using the Ground Penetrating Radar (GPR) method to detect possible zones of contamination caused by derivatives of hydrocarbons in service stations of the urban region of the city of Abaetetuba, in the state of Pará. The methodology was applied in service stations because they are the main potential source of soil and ground water contamination by fuel in the cities. Basic concepts about oil and contamination and its interaction with the ground are presented, together with the basic principles that allow the understanding of the GPR method as applied to the addressed problem. During the work, the depth to the water table was measured to construct an underground flow map. The geophysical interpretation was assisted by the knowledge of the local underground water flow that gives indication on the direction of contamination movement. The correlation of the GPR data with the underground flow and the information about the stations history allowed to classify them as suspected of producing contamination and possibly contaminated.
Acesso aberto (Open Access)
Estudo de pluma de contaminação por combustível com o método GPR e desenvolvimento de simulador geofísico para fins educativos
(Universidade Federal do Pará, 2009) REIS JÚNIOR, João Andrade dos; SILVA, Lúcia Maria da Costa e; http://lattes.cnpq.br/8612431024609774
The geophysical investigation of a possible hydrocarbon-contaminated site in Belém, Pará, state of Brazil, as well as the development of a geophysical simulator for education are described in this work. Thirteen profiles have been done with the electromagnetic geophysical method of Ground Penetrating Radar (GPR). The geophysical results together with the preexisting results from boreholes, Volatile Organics Compounds (VOC) and Benzene-Tolueno-Etil-benzene-Xileno (BTEX) had identified zones of low reflection of the electromagnetic signal (attenuated zones) in areas with dominantly sand, which could indicate the presence of contamination. The GPR profiles were repeated in the rainy period. This showed a reduction of the attenuation in zones in sand, which could indicate the leaching of the organic acids derived from the biodegradation of the hydrocarbons, as well as an increase in the attenuation in clay-rich zones, due the high porosity of the clay and also, possibly due to the increase of the biodegradation of the hydrocarbons that are restrained in the clay. The result of this investigation is the first case used in the geophysical simulator, an experiment that allows one to show the use of different geophysical methods. The simulator has two computational screens, one for simulation of the selected subsurface model (for example the hydrocarbon-contaminated site), and a screen above the first one that shows the geophysical results obtained for the subsurface model when an optics unit is moved along the model transect. The simulator uses analog modeling with the help of computational aids that are not yet reported in the literature; one can show different studies that were done in the past and which are now parts of dissertations and theses. The simulator can be moved to companies, schools, universities and government agencies, that make or can make use of Geophysics. Additionally, it can be taken to parks and schools, in order to contribute to the dissemination of Geophysics as a tool in the management of contaminated areas. Finally, the simulator will be useful for calling the attention of the population to different types of problems, as well as to instruct them about these problems and their solutions.
Acesso aberto (Open Access)
Geofísica aplicada à Arqueologia: investigação no Sítio Histórico Engenho Murutucu, em Belém, Pará
(Universidade Federal do Pará, 2007-08-21) MELO, Marina da Silveira e; LUIZ, José Gouvêa; http://lattes.cnpq.br/8676530374310847
This research sought through geophysical methodology the indication of possible locations of buried remains of occupation and foundations of the old construction of a slave quarter in the Engenho Murutucu, a historical site that has importance and relevance for the history of Pará. Following a magnetic map constructed with data from a previous research, 26 GPR profiles were carried out in the area using a 400 MHz antenna. The investigated depth in the GPR profiles was around 1,75 m. The analysis and correlation of the magnetic and GPR data allowed to reach the purpose of the research. The resulting geophysical indications will guide the future archaeological interventions in the site.
Acesso aberto (Open Access)
GPR aplicado à arqueologia nas áreas do porto da Cargill (Santarém/PA) e no Palacete Faciola (Belém/PA)
(Universidade Federal do Pará, 2012) SOUZA, Danusa Mayara de; LUIZ, José Gouvêa; http://lattes.cnpq.br/8676530374310847
This study was conducted in two areas. The first, located at the backyard of the Palacete Faciola, Belém/PA and, the second, named 4A, in the Archaeological Site PA-ST-42, located at the Port of Santarém/PA. The geophysical survey described in this work was undertaken in order to assist in archaeological prospecting, indicating places for future excavations in order to detect structures and/or artifacts buried on the sites. The radargrams acquired in both areas showed several anomalous features. Until the finish of this work any excavation had been undertaken in Palacete Faciola. In 4A area, however, two trenches were opened revealing various archaeological fragments.
Acesso aberto (Open Access)
Gradiometria magnética e GPR aplicados à arqueologia em sítio estuarino em Penalva - MA
(Universidade Federal do Pará, 2012-11-20) ROCHA, Herson Oliveira da; SILVA, Marcos Welby Correa; http://lattes.cnpq.br/3213216758254128
This research presents the results of the application of geophysical methods noninvasive, in order to indicate possible sites of deposition of materials in archaeological survey at a site located in the municipality of estuarine Penalva in the state of Maranhão. The methods used were Magnetometry and Ground Penetrating Radar (GPR). The magnetic measurements were used to indicate the locations for excavation. The GPR was used to confirm the anomalies generated by the magnetic method, providing fewer errors when the magnetic anomalies are not caused by archaeological features. Were 14 profiles performed GPR using an antenna 400 MHz and 1664 magnetic measurements using the magnetometer. During the archaeological survey conducted, based on the geophysical anomalies provided by the team led by archaeologists Deusdedit Carneiro Leite Filho and Luiz Fernando Tavares Marques made five excavations at the site, which allowed them to rescue several ceramic pieces. The results presented in this study allowed us to verify and evaluate the potential of geophysical prospecting method to assist in archaeological studies.
Acesso aberto (Open Access)
High resolution GPR applied to the “Capela Pombo”
(Universidade Federal do Pará, 2016-02-29) ESPEJO ZEBALLOS, Manuel Alejandro Junior; SILVA, Marcos Welby Correa; http://lattes.cnpq.br/3213216758254128
In this work was applied electromagnetic method (GPR), to identify surface layers in a speci c urban environment. The measurements were performed to map the surface layers and artifacts that make up the study area "Capela de Nosso Senhor dos Passos - a Capela Pombo" in the Barrio of Campina-Bel em. This chapel has a previous work that rescues the importance y architectural features that it has, together with the evidence recollected by the author Dominic Savio de Castro Oliveira, who noted the historical importance that has not only to be the last private chapel in the city of Belém, this author also acknowledges her design as an Italian architect's work possible Guissepi Jos e Antonio Landi. The pro les obtained after corresponding processing procedure, show that this probably presences of structures, rest of the previous building structure, which previously was in this space. The study aimed to identify anomalies. The study aimed to identify structural abnormalities, as well as possible characteristic burials of the time when it was actively used. The results of the GPR measurements were encouraging, since the method presented response of approximately 1.80 meters deep, one can identify anomalies control for the reasons as presented Chapel, and present possible anomalies related to structural foreign bodies.
Acesso aberto (Open Access)
Implantação do campo de testes da UFPA para medidas geofísicas
(Universidade Federal do Pará, 2013) ALVES, Jerry Williamis Lima; LUIZ, José Gouvêa; http://lattes.cnpq.br/8676530374310847
We describe the results obtained during the implementation of the Federal University of Pará test site for geophysical measurements. The work was done in three stages. In the first stage, preliminary studies were accomplished to know the physical background of the area. In the second, artifacts were buried to simulate geophysical anomalies in the measurements. In the third one, new measures were performed to detect anomalies caused by the buried artifacts. Only a part of the artifacts that are scheduled for burial was buried in the site. The buried artifacts are metal pipes, metal drums, and plastic drums. The measures implemented in the first and third stages involved the methods of Electrical Resistivity, Ground Penetrating Radar (GPR), Electromagnetic and Magnetic. The measurements performed in the third stage showed the presence of artifacts in the actual position where they were buried, which turns the area suitable to serve as a training site for geophysical experimental practices.
Acesso aberto (Open Access)
Investigação com os métodos GPR e magnético de urnas funerárias do Sítio Nossa Senhora do Perpétuo Socorro (Pará)
(Universidade Federal do Pará, 2012-09-21) SILVEIRA, Eric Sandro Ferreira da; SILVA, Lúcia Maria da Costa e; http://lattes.cnpq.br/8612431024609774
This paper presents the results of the application of geophysical methods in the selection of potential areas for archeological site at Nossa Senhora do Perpétuo Socorro in the state of Pará. The site has urns indigenous outcropping and sub-outcropping plenty of archaeological interest. The methods used were Magnetometry and Ground Penetrating Radar (GPR). The magnetic measurements were employed to indicate the most appropriate sites for excavation greatly reducing the potential areas. The GPR was used to confirm the anomalies detected by magnetic measurements and provide a better spatial assessment both horizontally and vertically, reducing the errors when they identify magnetic anomalies that are not caused by archaeological features. The study methodology was based on comparison of anomalies obtained from unknown areas which anomalies from areas where exists urns and roots, characterizing and grouping these anomalies.
Acesso aberto (Open Access)
Investigação geofísica ambiental e forense nos cemitérios do Benguí e do Tapanã (Belém - PA)
(Universidade Federal do Pará, 2009-04-06) NASCIMENTO, Waldemir Gonçalves; SILVA, Lúcia Maria da Costa e; http://lattes.cnpq.br/8612431024609774
The Geophysics is an useful tool in the study of the contamination of water caused by cemeteries, and in the forensic investigation as well as. The contamination caused by cemeteries is still a theme little studied. Besides, forensic Geophysics is almost unknown in Brazil. To study those two themes – cemeteries and forensic targets – two public cemeteries were chosen: the cemetery of Bengui, already disabled, and the cemetery of Tapanã. The geophysical investigation in the two cemeteries was accomplished with two electromagnetic methods: ground penetrating radar (GPR) and Slingram of low induction number (low induction number – LIN). In the cemetery of Bengui, the GPR method was tested for the detection of the ground-water level because in the implantation of a cemetery, the most important information is the depth of the aquifer. In the Cemetery of Tapanã, where the Controlled Test Site for Forensic Geophysics, Environmental and of Rescue, denominated FORAMB, was implanted, GPR and Slingram were used in monthly surveys in order to detect the ground-water level, monitoring the development of the contamination and, especially, to find forensic objectives (a corpse, a box simulating a tunnel and a box with iron metal pieces simulating weapons). The GPR method was shown effective in all of the studies, especially in the delineation of the forensic objectives. The Slingram didn’t supply useful information.
Acesso aberto (Open Access)
Investigação geofísica da contaminação por derivados de hidrocarbonetos nas redondezas do Posto Cristal (Belém-Pa)
(Universidade Federal do Pará, 2013) SILVA, Márcio Antonio dos Santos; SILVA, Lúcia Maria da Costa e; http://lattes.cnpq.br/8612431024609774
Acesso aberto (Open Access)
Investigação geofísica forense e antropológica com o método GPR no cemitério do Tapanã e no cemitério perdido de Mosqueiro (Belém, Pará)
(Universidade Federal do Pará, 2013-03-22) BRASIL, Diogenes Leão; SILVA, Lúcia Maria da Costa e; http://lattes.cnpq.br/8612431024609774
This work was accomplished with ground penetrating radar (GPR), a geophysical method used to investigate the shallow subsurface with high resolution in a non-destructive and noninvasive way. The survey was conducted in two locations in the metropolitan region of Belém, Pará State (Brazil), with 200 and 400 MHz antennas, both in the Tapanã cemetery: the first located in the test site for Controlled Testing of Forensic Geophysics, Environmental and Rescue (FORAMB) and the second one, in a burial zone with concrete cover. Surveys were also conducted in the northwest portion of Mosqueiro Island, across Marajó Bay, with a 400 MHz antenna, where reports of traces of a non-registered cemetery that would have been abandoned for about 80 years and could have been the final destination of cabanos, slaves and indians.These reports led researchers from the Federal University of Pará (UFPA) to visit the site in 1986 to test the veracity of the reports. At FORAMB the monitoring of the three targets that were buried there in 2007 was continued: a human body in a shallow grave 0.8 m deep, a tunnel simulated by a hollow wooden box placed 1 m deep and a box with metal, simulating weapons, deposited at 0.8 m depth. In the burial zone with concrete cover, the survey efforts focused on the effect of the concrete cover.The results obtained in the Tapanã cemetery show the usefulness of GPR in viewing targets under shallow soil cover and saturated clay, typical of the Amazon region, even when it is covered by a layer of concrete. These results reinforce the importance of pooling 2D and 3D data for interpretation of results; the GPR profiles over the concrete covering the bodies in various ages of burial, moreover, show significant variations of the responses, partly observed in other studies. The Mosqueiro results showed that ancient targets in climatic and geological conditions of the Amazon region, do not allow easy detection. It is possible that the remains of the decomposed bodies are not amenable to detection, but the discontinuity of the strata above the burial due to excavation, and the resulting concavity of the collapsed grave infill material may be diagnostic.
Acesso aberto (Open Access)
Investigações ambiental e forense com os métodos geofísicos radar de penetração do solo, polarização induzida e eletrorresistividade no Cemitério do Tapanã, Belém/Pará
(Universidade Federal do Pará, 2010-04-30) CATETE, Clístenes Pamplona; SILVA, Lúcia Maria da Costa e; http://lattes.cnpq.br/8612431024609774
The cemeteries are considered potential sources of underground water contamination. Since the use of geophysics in the mapping of the hydrostatic level (HL) has become a very important tool in the environmental monitoring, it makes possible to verify adequate or inadequate areas for burials in cemeteries. In the other hand, the localization of underground clandestine hollows and tunnels, can be of utility for the Forensic Science. In this work, geophysical methods were applied for mapping the HL in a cemetery and to find buried structures related to the Forensic Science. Ground Penetrating Radar (GPR) was used in the mapping of the HL in the whole Tapanã cemetery, while the resistivity and induced polarization (IP) methods were applied on a test site built in that cemetery for forensic, environmental and resgate related geophysical studies. The results with the GPR showed that the HL depth in the Tapanã cemetery varies from 7 m, at high topographic levels, to 1 m, at low topographic levels. The IP was sensible to the presence of a body buried in a shallow hollow as the clandestine hollows are and showed only fair results for a tunnel. The resistivity was effective for both the buried body and the tunnel, with better definition of the tunnel. The methods gave good results even within the weathering layer rich in clay that normally occurs in the Amazon region.
Acesso aberto (Open Access)
O método GPR aplicado à arqueologia no Sítio PA-ST-42: porto de Santarém, Pará
(Universidade Federal do Pará, 2014-03-06) FURTADO, Carla Patrícia Queiroz; SILVA, Marcos Welby Correa; http://lattes.cnpq.br/3213216758254128
Acesso aberto (Open Access)
O método GPR aplicado à localização de tubulações utilizadas no abastecimento de água na região urbana do município de Belém - Pará
(Universidade Federal do Pará, 2010) PINTO, Gerson Pompeu; SILVA, Marcos Welby Correa; http://lattes.cnpq.br/3213216758254128
This work was carried out to evaluate the feasibility of the method GPR (Ground Penetrating Radar) method to locate steel, cement-amianthus, PVC and cast iron pipes of several diameters, used by the Companhia de Saneamento do Pará (COSANPA) for water supply to the population of the urban area of Belém-Pará. To achieve this goal 14 profiles were performed at 6 distinct sites of Belém's urban area, in order to identify 13 targets, using the of 200 MHz and 400 MHz antenna, commonly used in this type of survey. The radargrams obtained with GPR allowed to identify almost all targets. surveyed. Only 3 of the 13 targets were not fully identified, leaving out only the targets of PVC of small gauge (50 mm and 75 mm). After the study, we concluded that the GPR method is very effective in this type of application and its use has great value in the location of the water supply network, what should greatly facilitate the work of expanding the network, as well as its maintenance.
Acesso aberto (Open Access)
Metodologia geofísica aplicada à pesquisa de salvamento arqueológico nos sítios Bittencourt, Jambuaçu e Jaburu, Estado do Pará
(Universidade Federal do Pará, 2006-05-02) ARAGÃO, Rigler da Costa; LUIZ, José Gouvêa; http://lattes.cnpq.br/8676530374310847
We present the results obtained in the application of geophysical methods to help the archaeological rescue of remains in the three following sites in Pará, northern of Brazil: Bittencourt, located in Abaetetuba; Jambuaçu, located in Moju; and Jaburu, located in Almeirim. Magnetometry, scintillometry and ground penetrating radar (GPR) were used in the study. Magnetic measurements were taken as the main tool to indicate places for excavation. GPR was used to confirm the anomalies detected with the magnetic method and provided a restriction to the magnetic anomalies caused by non-archaeological artifacts. Scintillometry was used as an attempt to map the archaeological black earth (ABE) or Terra Preta Arqueológica (TPA) soil through the detection of natural gamma ray emitted by the ground. The excavations carried out on the indications of magnetometry and GPR yielded the recovery of ceramics, faience, lithics, and iron artifacts. The scintillometric data showed that exist a good correlation between low radiation and large thickness of ABE (TPA). The used geophysical methodology proved to be efficient and quick with no destructive impact to the sites.
Acesso aberto (Open Access)
Metodologia geofísica aplicada ao estudo arqueológico dos sítios Bittencourt e Jambuaçu, Estado do Pará
(2010-06) ARAGÃO, Rigler da Costa; LUIZ, José Gouvêa; LOPES, Paulo Roberto do Canto
Magnetic, total count gamma radiation, and Ground Penetrating Radar (GPR) measurements were carried out on two archaeological sites located adjacent to the place where a miner duct will be buried. The aim of the measurements was to indicate the optimal áreas for archaeological excavation to find subsurface remains related to ancient communities that lived in the sites. Magnetic measurements showed anomalies that lead to the discovery of a large amount of ceramic fragments and other remains. Gamma radiation allowed discriminating argillaceous from sandy soil, an important result since sandy soil can be correlated to the archaeological layer, where remains are normally found. Ground penetrating radar confirmed the magnetic anomalies and showed several other anomalous features not related to the archaeological remains.
Acesso aberto (Open Access)
A viabilidade do método GPR para o mapeamento de camadas de bauxitas laterítica em Paragominas-PA e de goethita em Xambioá-TO
(Universidade Federal do Pará, 2011-08-31) DUARTE, Gildenilson Mendes; SILVA, Marcos Welby Correa; http://lattes.cnpq.br/3213216758254128
In this work we applied the GPR electromagnetic method mapping of layered deposits of minerals in two different environments. Measurements were made with the aim of mapping layers that form deposits of supergene origin of lateritic bauxite, and Goethite. The surveys for the mapping of layers of bauxites were conducted within the mine company Vale and also along the highway PA 256, in the municipality of Paragominas-PA. Resistivity tests were performed within the mine bauxite on a thick capping of clay in an attempt to correlate the variations of resistivity with the lithologic of the studied area, because the GPR measurements were not successful on this capping due the attenuation of the radar wave. The measures for mapping layers Goethite were carried inside a private property, located on the stretch between the towns of Xambioá and Vanderlândia, Tocantins state, near the Araguaia Belt. The study had as main objective to identify parameters such as depth and thickness of mineralized zones, which may aid in the work of exploitation of ores. The results of GPR measurements were very satisfactory, because the method presented a good response for both types of ores investigated, making it possible to characterize the layers and to verification its depths and thicknesses.