Reservoir characterization is one of the most important problems in petroleum engineering. It involves forward reservoir modeling that predicts the fluid behavior in the reservoir and inverse problem that calibrates created reservoir models with given data. In this dissertation, we focus on two problems in the field of reservoir characterization: depth of investigation in heterogeneous reservoirs, and history matching and uncertainty quantification of channelized reservoirs. The concept of depth of investigation is fundamental to well test analysis. Much of the current well test analysis relies on analytical solutions based on homogeneous or layered reservoirs. However, such analytic solutions are severely limited for heterogeneous and fractured reservoirs, particularly for unconventional reservoirs with multistage hydraulic fractures. We first generalize the concept to heterogeneous reservoirs and provide an efficient tool to calculate drainage volume using fast marching methods and estimate pressure depletion based on geometric pressure approximation. The applicability of proposed method is illustrated using two applications in unconventional reservoirs including flow regime visualization and stimulated reservoir volume estimation. Due to high permeability contrast and non-Gaussianity of channelized permeability field, it is difficult to history match and quantify uncertainty of channelized reservoirs using traditional approaches. We treat facies boundaries as level set functions and solve the moving boundary problem (history matching) with the level set equation. In addition to level set methods, we also exploit the problem using pixel based approach. The reversible jump Markov Chain Monte Carlo approach is utilized to search the parameter space with flexible dimensions. Both proposed approaches are demonstrated with two and three dimensional examples.

Inversion and Depth Range of Dipole Electromagnetic Induction Measurements in Geophysics Fernando César Moura de Andrade Institute of Hydrogeology, Engineering Geology and Applied Geophysics Faculty of Science, Charles University Electromagnetic induction geophysical methods are, basically, composed by a transmitter which produces a magnetic field and a set of receivers which measure the primary magnetic field, from the transmitter, superimposed by secondary magnetic fields inducted in the subsurface. Equipment operating at, relatively, low frequencies and with short distances between the transmitter and the receivers are usually called conductivity meters and operate at low inductions numbers. The depth of investigation, in such kind of equipment, depends mainly on the transmitter-receiver distance, on the orientations of the magnetic dipoles and the height of the instrument from the ground, in order that a depth sounding can be done changing these parameters in a single measurement location. Making a series of these multi-configuration measurements, two-dimensional, or even three-dimensional surveys, can be performed and, subsequently, inverted in order to produce an image of the subsurface of the earth. Forward modelling and inversion of multi-configuration electromagnetic induction data can be made...

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-12-27T10:56:51Z No. of bitstreams: 2 Dissertação - Fernando Moreira Viana - 2016.pdf: 6105282 bytes, checksum: 6822f2ad13c8ed286d41535c02c26b87 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-12-27T10:57:33Z (GMT) No. of bitstreams: 2 Dissertação - Fernando Moreira Viana - 2016.pdf: 6105282 bytes, checksum: 6822f2ad13c8ed286d41535c02c26b87 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-12-27T10:57:33Z (GMT). No. of bitstreams: 2 Dissertação - Fernando Moreira Viana - 2016.pdf: 6105282 bytes, checksum: 6822f2ad13c8ed286d41535c02c26b87 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-11-29 / This work proposes a methodology for interpretation of soil resistivity measurements obtained using the arrangement of four electrodesWenner, Schlumberger and Schlumberger-Palmer. Displays can be compared apparent resistivity curves when the quantity used in the abscissa is the effective depth of investigation. This magnitude that depends on the geometry of the electrodes, namely the positioning of both current electrodes and the potential electrodes. The work also features in an innovative way, an algorithm for soil stratification from resistivity measurements obtained with the Schlumberger arrangement. The same is based on the method of complex images and propose a finite number of complex exponentials to represent the kernel function. Several simulations are performed, proving the efficiency and effectiveness of the proposed algorithm. / Este trabalho propõe uma metodologia para interpretação de medições de resistividade do solo obtidas utilizando os arranjos de quatro eletrodos de Wenner, Schlumberger e Schlumberger-Palmer. Mostra ser possível comparar curvas de resistividade aparente quando a grandeza utilizada no eixo das abscissas é a profundidade efetiva de investigação. Grandeza esta que depende da geometria dos eletrodos, ou seja, do posicionamento tanto dos eletrodos de corrente como dos eletrodos de potencial. O trabalho apresenta também, de forma inovadora, um algoritmo para estratificação do solo a partir de medições de resistividade obtidas com o arranjo de Schlumberger. O mesmo baseia-se no método das imagens complexas e na proposição de uma série finita de exponenciais complexas para representar a função kernel. Simulações diversas são realizadas, comprovando a eficiência e a eficácia do algoritmo proposto.