Banca de QUALIFICAÇÃO: DANIELLE CRISTINA COSTA DE SOUZA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : DANIELLE CRISTINA COSTA DE SOUZA
DATE: 12/05/2025
TIME: 14:00
LOCAL: Remota (Google Meet)
TITLE:

Time-frequency analysis with the q-Gaussian W transform in unconventional oil and gas reservoirs.

KEY WORDS:

Time-frequency analysis, Nonstationary time series, Non-Gaussian distributions, W transform, Tsallis entropy, unconventional reservoir.

PAGES: 135
BIG AREA: Ciências Exatas e da Terra
AREA: Física
SUMMARY:

Unconventional reservoirs exhibit complex geological structures and often present unfavorable petrophysical properties, such as high heterogeneity, low porosity, and permeability, which complicate the interpretation of seismic signals. Therefore, it is crucial to develop reliable methods that utilize seismic data directly for the detection and monitoring of hydrocarbons in these reservoirs. Time-frequency analysis is another tool that allows the visualization of the energy or amplitude distribution of a signal in the time and frequency domains, being essential for seismic data processing and interpretation. This technique is critical for both reservoir characterization and hydrocarbon detection. Reservoir characterization requires the estimation of physical properties over extensive subsurface regions, a process typically carried out through geophysical inversion. By incorporating dominant frequency information into its convolution kernel, the W transform improves time-frequency resolution compared to the well-established Stockwell transform. However, the W transform is constructed from a Gaussian window function, which may limit its use for time series that are not concentrated in the harmonic domain. We generalize the W transform by introducing a finite-variance q-Gaussian distribution derived from nonextensive statistical mechanics. The proposed q-Gaussian W transform features a free parameter q to control the locality of the window function. We verify the time-frequency characteristics of this new transform using two synthetic nonstationary signals and field seismic data as case studies. We demonstrate that this non-Gaussian kernel with nonzero kurtosis enhances the energy concentration of time-frequency spectra.

COMMITTEE MEMBERS:
Presidente - 1379465 - GILBERTO CORSO
Externa ao Programa - 2218779 - HELENICE VITAL - nullInterno - 2492756 - JOAO MEDEIROS DE ARAUJO