Research Projects

Ilya Tsvankin

University Distinguished Professor
Co-Leader, Center for Wave Phenomena

The main focus of my research group, the A(nisotropy)-Team, is on modeling, inversion, and imaging of seismic reflection and borehole data from anisotropic media. The current A-Team research portfolio emphasizes full-waveform inversion (FWI) for elastic anisotropic models, time-lapse monitoring of CO2 sequestration, and novel applications of machine-learning (ML) techniques. In addition to CWP sponsors, the team collaborates with the Reservoir Characterization Project (RCP) at Mines and several other academic groups, Los Alamos and Lawrence Berkeley National Laboratories, and Earth Science Analytics.

Among my current and recently completed research projects are:

• Time-lapse elastic full-waveform inversion (FWI) for transversely isotropic media with a vertical (VTI) and tilted (TTI) symmetry axis (with Y. Liu).
• High-resolution seismic monitoring of CO2 sequestration using time-lapse FWI of seismic data combined with neural networks (with Y. Liu and colleagues from the Los Alamos and Lawrence Berkeley National Labs).
• Facies-constrained elastic FWI for VTI and orthorhombic media [with S. Singh and E. Zabihi Naeini (Earth Science Analytics)].
• Supervised and semisupervised machine-learning algorithms for building 3D facies models using borehole data and for predicting facies distribution from migrated seismic sections [with S. Singh and E. Zabihi Naeini (Earth Science Analytics)].
• Sensitivity analysis of 3D elastic FWI for orthorhombic media with a horizontal symmetry plane (with S. Singh).
• Mimetic approach to anisotropic coupled-domain finite-difference (FD) modeling (with H. Sethi and J. Shragge).
• Application of mimetic FD propagators to FWI of offshore seismic data (with H. Sethi and J. Shragge).
• Extension of elastic FWI to tilted orthorhombic models and application of lithologic constraints to reduce the inversion nonuniqueness (with A. Kumar).
• 3D anisotropic FWI of seismic data for estimating reservoir attributes [with S. Singh, T. Alkhalifah (KAUST), E. Zabihi Naeini (Earth Science Analytics), and J. Cheng (Tongji University)].
• Microseismic event location and velocity analysis for VTI and orthorhombic models by FWI of downhole data (with O. Jarillo Michel).
• Wave-equation migration velocity analysis for VTI and TTI media [with V. Li, A. Guitton, and T. Alkhalifah (KAUST)].
• Compensation for anisotropic attenuation in reverse-time migration (RTM) and microseismic source imaging [with T. Bai and T. Zhu (Penn State)].
• Source-independent waveform inversion for VTI attenuation parameters (with T. Bai).
• Multicomponent stacking-velocity tomography for tilted orthorhombic media (with Q. Liu).
• Separation of diffractions and diffraction-based anisotropic parameter estimation (with Y. Arora).
• 3D acoustic waveform inversion of wide-azimuth data for orthorhombic models (with H. Wang).
• Sensitivity analysis and optimal parameterization of elastic FWI for VTI media (with N. Kamath).