Produção Científica



Dissertação de Mestrado
03/11/2015

Paulo Eduardo Pasquini Marcondes. Relações experimentais entre tensão e propriedades de fratura em meios sintéticos anisotrópicos. 2012.
Paulo Eduardo Pasquini Marcondes. Relações experimentais entre tensão e propriedades de fratura em meios sintéticos anisotrópicos. 2012. Dissertação (Mestrado em Engenharia de Petróleo) - Universidade Estadual de Campinas, Petrobras. Orientador: Joerg Dietrich Wilhelm Schleicher.
Dissertação de Mestrado
03/11/2015

Francisco Ortega Gamboa. Processamento de Dados Sísmicos com Grandes Afastamentos: Dados Sintéticos e Linha Sísmica do Campo de Tenerife, Colômbia. 2012.
Francisco Ortega Gamboa. Processamento de Dados Sísmicos com Grandes Afastamentos: Dados Sintéticos e Linha Sísmica do Campo de Tenerife, Colômbia. 2012. Dissertação (Mestrado em Geofísica) - Universidade Federal da Bahia, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior. Orientador: Amin Bassrei.
Tese de Doutorado
03/11/2015

José Jadsom Sampaio de Figueiredo. Modelagem física de meios fraturados anisotrópicos e estudo da birrefringência sísmica em função dos parâmetros anisotrópicos.
José Jadsom Sampaio de Figueiredo. Modelagem física de meios fraturados anisotrópicos e estudo da birrefringência sísmica em função dos parâmetros anisotrópicos. 2012. Tese (Doutorado em Engenharia do Petróleo) - Universidade Estadual de Campinas, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior. Orientador: Joerg Dietrich Wilhelm Schleicher.
Tese de Doutorado
03/11/2015

Rodrigo Bloot. Modelagem e estudo analítico da equação da onda elástica em um meio VTI.
Rodrigo Bloot. Modelagem e estudo analítico da equação da onda elástica em um meio VTI. 2012. Tese (Doutorado em Matemática Aplicada) - Universidade Estadual de Campinas. Orientador: Joerg Dietrich Wilhelm Schleicher.
Tese de Doutorado
03/11/2015

Valdelírio da Silva e Silva. Modelagem bidimensional do método eletromagnético a multi-frequência - EMMF
Valdelírio da Silva e Silva. Modelagem bidimensional do método eletromagnético a multi-frequência - EMMF. 2012. Tese (Doutorado em Geofísica) - Universidade Federal do Pará. Co-Orientador: Carlos Alberto Dias.
Artigo em Revista
01/09/2015

Mapping Neogene and Quaternary sedimentary deposits in northeastern Brazil by integrating geophysics, remote sensing and geological field data
Neogene and late Quaternary sedimentary deposits corresponding respectively to the Barreiras Formation and Post-Barreiras Sediments are abundant along the Brazilian coast. Such deposits are valuable for reconstructing sea level fluctuations and recording tectonic reactivation along the passive margin of South America. Despite this relevance, much effort remains to be invested in discriminating these units
in their various areas of occurrence. The main objective of this work is to develop and test a new methodology for semi-automated mapping of Neogene and late Quaternary sedimentary deposits in northeastern Brazil integrating geophysical and remote sensing data. The central onshore Paraíba Basin was selected due to the recent availability of a detailed map based on the integration of surface and subsurface geological data. We used airborne gamma-ray spectrometry (i.e., potassium-K and thorium-Th concentration) and morphometric data (i.e., reliefedissection, slope and elevation) extracted from the digital elevation model (DEM) generated by the Shuttle Radar Topography Mission (SRTM). The procedures included: (a) data integration using geographic information systems (GIS); (b) exploratory statistical analyses, including the definition of parameters and thresholds for class discrimination for a set of sample plots; and (c) development and application of a decision-tree classification. Data validation was
based on: (i) statistical analysis of geochemical and airborne gamma-ray spectrometry data consisting of K and Th concentrations; and (ii) map validation with the support of a confusion matrix, overall accuracy, as well as quantity disagreement and allocation disagreement for accuracy assessment based on field points. The concentration of K successfully separated the sedimentary units of the basin from Precambrian basement rocks. The reliefedissection morphometric variable allowed the discrimination between the Barreiras Formation and the Post-Barreiras Sediments. In addition, two units of the latter (i.e., PB1 and PB2) previously mapped in the field were promptly separated based on Th concentration. A regression analysis indicated that the relationship between geophysical and geochemical values obtained for the PB1, PB2 and Barreiras Formation is significant (R-squared ¼ 0.91; p-value <0.05). Map validation
presented a high overall accuracy of 84%, with a coefficient of quantity disagreement of 12% and a coefficient
of allocation disagreement of 8%. These results indicate that the methodology applied in the
central onshore Paraíba Basin can be successfully used for mapping the Barreiras Formation and Post-
Barreiras Sediments in other areas of the Brazilian coast. The ability to rapidly and precisely map
these units using such methodology could reveal their geographic distribution along the northeastern
coast of Brazil.
Artigo em Revista
01/09/2015

Neotectonic reactivation of shear zones and implications for faulting style and geometry in the continental margin of NE Brazil
The eastern continental margin of South America comprises a series of rift basins developed during the breakup of Pangea in the Jurassic–Cretaceous. We integrated high resolution aeromagnetic, structural and stratigraphic data in order to evaluate the role of reactivation of ductile, Neoproterozoic shear zones in the deposition and deformation of post-rift sedimentary deposits in one of these basins, the Paraíba Basin in northeastern Brazil. This basin corresponds to the last part of the South American continent to be separated fromAfrica during the Pangea breakup. Sediment deposition in this basin occurred in the Albian–Maastrichtian, Eocene–Miocene, and in the late Quaternary. However, our investigation concentrates on the Miocene–Quaternary, which we consider the neotectonic period because it encompasses the last stress field. This consisted of an E–W-oriented compression and a N–S-oriented extension. The basement of the basin forms a slightly seaward-tilted ramp capped by a late Cretaceous to Quaternary sedimentary cover ~100–400 m thick. Aeromagnetic lineaments mark the major steeply-dipping, ductile E–W- to NE-striking shear zones in this basement. The ductile shear zones mainly reactivated as strike-slip, normal and oblique-slip faults, resulting in a series of Miocene–Quaternary depocenters
controlled by NE-, E–W-, and a few NW-striking faults. Faulting produced subsidence and uplift that are largely responsible for the present-day morphology of the valleys and tablelands in this margin. We conclude that Precambrian shear zone reactivation controlled geometry and orientation, aswell as deformation of sedimentary deposits, until the Neogene–Quaternary.
Artigo em Revista
01/09/2015

GPR investigation of karst guided by comparison with outcrop and unmanned aerial vehicle imagery
The increasing importance of carbonate rocks as aquifers, oil reservoirs, and for urban problems is demanding detailed characterization of karst systems, a demand that can be partially satisfied with GPR imaging. However,the goal of imaging and interpreting karstified carbonate rocks is notoriously difficult due to the complex nature of the geometry of the dissolution and the GPR intrinsic limitations. One way forward is the direct comparison of GPR images with similar outcropping rocks. A joint study involving a 200 MHz GPR survey, unmanned aerial vehicle imagery (UAV), and outcrop characterization is presented aiming to improve the interpretation of
sedimentary structures, fractures and karst structures in GPR images. The study area is a 500 m wide and 1000m long carbonate outcrop of the Jandaíra Formation in Potiguar basin, Brazil, where sedimentary, fracture,and karst features can be directly investigated in both vertical and horizontal plan views. The key elements to
interpret GPR images of karstified carbonate rocks are: (1) primary sedimentary structures appear in radargrams as unaltered imaged strata but care must be taken to interpret complex primary sedimentary features, such as those associated with bioturbation; (2) subvertical fractures might appear as consistent discontinuities in the imaged strata, forming complex structures such as negative flowers along strike–slip faults; (3) dissolution may create voids along subhorizontal layers, which appear in radargrams as relatively long amplitude shadow zones; and (4) dissolutionmay also create voids along subvertical fractures, appearing in radargrams as amplitude
shadow zones with relatively large vertical dimensions, which are bounded by fractures.
Artigo em Revista
23/07/2015

An identification problem related to the Biot system.
In this paper, we study the propagation of elastic waves in porous media governed by the Biot equations in the low frequency range. We prove the existence and uniqueness result both for the direct problem and the inverse one, which consists in identifying the unknown scalar function f(t) in the body density force f(t)
Artigo em Revista
23/07/2015

Prony Filtering of Seismic Data
Prony filtering is a method of seismic data processing which can be used to solve various geological and production tasks, involving an analysis of target horizons characteristics and a prediction of possible productive zones. This method is based on decomposing the observed seismic signals by exponentially damped cosines at short-time intervals. As a result, a discrete Prony spectrum including values of four parameters (amplitude, damping factor, frequency, phase) can be created. This decomposition occurs at many short-time intervals moving along an observed trace. The combined Prony spectrum of the trace can be used to create images of the trace through a selection of some values of the parameters. These images created for all traces of a seismic section provide an opportunity for locating zones of frequency-dependent anomalous scattering and absorption of seismic energy. Subsequently, the zones can be correlated with target seismic horizons. Analysis and interpretation of these zones may promote understanding of the target horizons features and help to connect these features with the presence of possible reservoirs.
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