My research interests focus on the realistic analysis and interpretation of field-based geophysical data using high performance computers. Analysis and interpretation of geophysical data in the framework of realistic geology is important to a variety of applications. For example, realistic subsurface properties are highly desirable for hydrocarbon and mineral exploration, or for civil engineering site investigations to ensure competent building foundations. During my graduate study at the University of Toronto and visiting fellowship at the Geological Survey of Canada, I focused on developing characterization and interpretation techniques capable of accounting for geological complexity that could not be handled efficiently with previous technology. For instance, I have developed methods to characterize heterogeneity and assess its impact on waves’ behavior and resource evaluation. I also developed a practical approach to efficiently map subsurface seismic velocity in complex geological environments such as permafrost and crystalline rocks. In my future research, I wish to maintain and develop cutting-edge geophysical techniques in characterizing and interpreting geology while preserving as much as possible the reality and complexity of the subsurface. More specifically, I plan to characterize the behavior of seismic waves in complex geology and to interpret geophysical data with exceptional accuracy.
My other research interests is travel time tomography. Fast sweeping method based adjoint travel time tomography has been implemented on Linux Cluster and is being tested on Mallik 3D and Burnt lake 3D seismic data sets. Joint inversion of both reflection time and transmission time is also covered by my software (to be named AdjointTomo). The high performance of AdjointTomo will be reported in my upcoming papers.
Waveform tomography is a straightforward extension from my travel time tomography experience. However, an efficient forward modeling engine is required. In travel time tomography, I used Fast Sweeping Method which can efficiently calculate the first arrivals. In waveform tomography, the efficient forward engine candidates are: Spectral Element Method (SEM: a high degree Finite Element method) and Discontinuous Galerkin Finite Element Method (DG-FEM, a combination of Finite Element Method and Finite Volume Method). Program codes implementing SEM in the public domain currently (by 2010) restricted to quadrilateral (2D) or hexahedral (3D) meshes. To mesh a complex structure using only these two types of elements is quite challenging. SEM using triangles or tetrahedral somehow loses its computational advantages. DG-FEM can be a better candidate to simulate seismic wave propagation in complex structures.