Tsvankin's work published in SEG's Geophysics

Ilya Tsvankin, a professor in the Geophysics Department and director of the Center for Wave Phenomena, published three papers with his students in the Special Section on Seismic Anisotropy in the July-August issue of the Society of Explorations Geophysicists journal Geophysics.

Tsvankin also served as one of the section editors and coauthored the introductory article of the summer issue.

The first paper is devoted to wavefield tomography, an accurate method for analyzing shale formations by building subsurface velocity models—especially useful in subsalt exploration in the Gulf of Mexico and other important hydrocarbon provinces. The paper was written in cooperation with Tariq Alkhalifah from the King Abdullah University of Science and Technology in Saudi Arabia, an affiliate faculty member in the Mines Geophysics Department.

With the goal of further characterizing oil and gas reservoirs, the second paper focuses on attenuation analysis of seismic waves, a method that allows researchers to uncover important information about the reservoir rocks such as the fluid type, saturation and fracture properties. Estimation of attenuation coefficients, however, remains a highly challenging problem—this paper develops an advanced method of attenuation analysis for heterogeneous, anisotropic media based on inverting the entire seismic trace (so-called waveform inversion).

The final paper looks into microseismicity, using geophysical waveform analysis to better understand microearthquakes generated during hydraulic stimulation of shale reservoirs. The researchers employ waveform inversion of borehole seismic data, demonstrating that waveforms of compressional and shear waves can provide accurate source locations of microseismic events along with the velocity model of the reservoir.

The papers included in the special section were presented at the 17^th International Workshop on Seismic Anisotropy (17IWSA) held at Horseshoe Bay, Texas, last year.