Navegando por Autor "SANTOS, Walleson Gomes dos"

Agora exibindo 1 - 2 de 2

Acesso aberto (Open Access)
Arranjos coplanar e coaxial nas sondas de perfilagem de poço: ferramentas triaxiais em reservatórios laminados
(Universidade Federal do Pará, 2007) SANTOS, Walleson Gomes dos; RÉGIS, Cícero Roberto Teixeira; http://lattes.cnpq.br/7340569532034401; CARVALHO, Paulo Roberto de; http://lattes.cnpq.br/6761774273543163
The triaxial or multicomponent induction tool was recently developed to solve the problems of conventional induction logging measurements in anisotropic formations. In this work are presented the triaxial induction sonde answers in reservoirs with thinly laminated sand-shale sequences. Reservoirs as these present the known macrocospic anisotropy, therefore, the results will demonstrate to the existence of both horizontal and vertical resistivity. Due the triaxial induction sonde to present two pairs of coplanar coils, which in general provide the values of vertical resistivity, this work presents initially an analytical and qualitative study of the answers obtained for coplanar array where the transmitter is considered a dipole. Also will be presented the analytical solution where the transmitter coil is evaluated as a loop of finite dimension.
Acesso aberto (Open Access)
Modelagem 1D e 2,5D de dados do método CSEM marinho em meios com anisotropia transversal inclinada
(Universidade Federal do Pará, 2014-02-28) SANTOS, Walleson Gomes dos; RÉGIS, Cícero Roberto Teixeira; http://lattes.cnpq.br/7340569532034401
In this work I present the solution to the electromagnetic field generated by a horizontal electric dipole in transversally isotropic media with vertical (TIV) as well as inclined (TII) symmetry axis. In one-dimensional models the electromagnetic field was obtained with two distinct methods: (1) For the TIV case, I have written a semi-analytical solution to the Maxwell’s equations, by using a vector potential formulation; (2) For the TII case, the field was represented as the composition of primary and secondary fields, where primary fields are those found in an underlying isotropic layered medium, and the secondary field is calculated numerically via the finite element method in the spatial Fourier transform domain (kx, ky, z). This last methodology was also used to calculate the fields in two-dimensional structures, including inclined anisotropy in any region of the models. In this 2,5D case, I have applied the finite element method in the (x, ky, z) do main. Here I have used unstructured meshes to discretise the media, and parallel programming to solve the linear systems of equations. The responses were used to study the effects of electrical anisotropy in marine CSEM data.