masterThesis
Um estudo de estratégias de inversão de dados sísmicos via inversão da forma de onda completa no domínio da frequência
Fecha
2019-12-27Registro en:
RÊGO, Raphael Carvalho de Lucena. Um estudo de estratégias de inversão de dados sísmicos via inversão da forma de onda completa no domínio da frequência. 2019. 54f. Dissertação (Mestrado em Ciência e Engenharia de Petróleo) - Centro de Ciências Exatas e da Terra, Universidade Federal do Rio Grande do Norte, Natal, 2019.
Autor
Rêgo, Raphael Carvalho de Lucena
Resumen
Full-Waveform Inversion is a powerful seismic imaging technique capable of recovering highresolution subsurface models from observed data. This inversion is a nonlinear problem
formulated as a local optimization problem that seeks to minimize the objective function in an
attempt to find values that fit the modeled and observed data. In order to minimize the
nonlinearity problem, a multiscale inversion approach is used to mitigate the sensitivity of the
problem to converging toward local minima. In this work, we studied the frequency domain
Full-Wave Inversion strategies (frequency and small frequency band inversion) with the
Marmousi model in the presence and absence of noise. Additionally, a hybrid regularization
based on Cauchy and Tikhonov constraints was proposed, in order to balance smoothness and
sparsity also in noise presence and absence situations. The tests showed a superiority in the use
of frequency band inversion. Moreover, for Marmousi, the proposed hybrid regularization was
able to satisfactorily invert the initial model and it is a good option for data inversions in the
absence of noisy components while Tikhonov was better adjusted considering the noise used
and the parameters of this work.