Hejun Zhu
SEG J. Clarence Karcher Award 2019
Hejun Zhu has published 10 articles in Geophysics, one in The Leading Edge, and other articles in international journals including Science and Nature. Zhu published 10 papers in 2018 alone, and he has been cited more than 600 times. His areas of interest include finding out how the earth works in a geologic, geodynamic, and tectonic sense, spanning the use of seismology in applied problems of earthquake hazard mitigation and resource exploration. His work is in fields as diverse as wavefield separation, beam migration with topography, least-squares migration, and regularization and uncertainty in full-waveform inversion. To quote one nominator: “… Hejun is one of the few scientists in our SEG community who is equally comfortable in the global seismology community.”
Biography Citation for the J. Clarence Karcher Award
by David Lumley
It is my great pleasure to give the award citation for Hejun Zhu, an assistant professor at the University of Texas at Dallas (UT Dallas). Hejun is receiving the prestigious SEG J. Clarence Karcher Award to recognize his significant contributions to the field of applied seismology as an outstanding early-career scientist. In my decades of academic and industry experience, Hejun certainly ranks in the top 1% of outstanding young scientists in the international SEG geophysics community.
A brief summary of Hejun’s remarkable achievements to date are as follows. He obtained a PhD in geophysics (2013) from Princeton University, supervised by Jeroen Tromp, followed by a position as the Jackson School Distinguished Postdoctoral Fellow in Geophysics, at the University of Texas at Austin (2013–15). In 2015, Hejun was appointed as an assistant professor at UT Dallas, where we are now colleagues together. Hejun has an impressive record of 28 peer-reviewed journal publications, including 11 in SEG’s top-ranked journal Geophysics, and 2 papers in the #1 ranked journals of Science and Nature Geoscience. Hejun has a combined 36-plus presentations and abstracts at SEG, American Geophysical Union (AGU), and other geophysical research meetings, and 38 invited talks at energy companies, universities, and national research labs. He has been research contributor to UT Austin and UT Dallas seismic industry research consortia valued at $300,000+ per year, and is a co-principal investigator of a new industry research consortium at UT Dallas with myself (Green Chair in Geophysics) and Sue Minkoff (Applied Mathematics). Hejun has been an SEG Active Member since 2016 (in addition to AGU and Society for Industrial and Applied Mathematics memberships), and is the faculty advisor for the SEG Student Chapter at UT Dallas. He has accomplished all of this in just five years since obtaining his PhD. Hejun’s list of achievements reads more like a well-established senior research scientist or full professor than those of a recent PhD graduate.
It is clear from the list of achievements above that Hejun has already made major contributions to the SEG community of applied geophysics during his young career. His research focuses on some of the most important topics of our time in applied seismology, including:
• exploration seismic imaging, including 3D finite-difference reverse time migration, least-squares migration, and incorporating the complex physics effects of elasticity, anisotropy, and Q attenuation; • full-waveform inversion, including practical improvements such as inverting the full Hessian operator, suppressing cycle-skipping, and including anisotropic viscoelastic wave propagation effects; • his research is being rigorously tested on industry-strength models (SEAM, Sigsbee etc.), and on real data sets provided by energy companies.
In addition to applied seismology, Hejun is one of the few scientists in our SEG community who is equally comfortable in the global seismology community. This is an exciting time of great cross-fertilization between the two communities in terms of dense receiver arrays, autonomous broadband nodes, wave-equation imaging and inversion methods, full-waveform inversion, continuous ambient noise recording and imaging, etc. Hejun is at the forefront of this cross-fertilization that will surely lead to major breakthroughs in both communities. His global seismology research interests include:
• ambient seismic noise imaging from continuously recording arrays for deep earth structure, also applicable to resource-scale overburden and reservoir imaging; • earthquake source mechanism and rupture processes, including both large magnitude earthquakes, and smaller magnitude microseismic events associated with induced seismicity, water injection, etc.; • seismic tomography for determining the earth’s deep structure, also applicable to surface and borehole geometry reflection and refraction seismic data; • numerical simulation methods of seismic wave propagation for large-scale 3D earth models, also applicable to SEAM-scale exploration and reservoir earth models.
Hejun and I recently combined funds and purchased the largest high-performance computational cluster on campus at UT Dallas for our research groups to work on all of the exciting seismic challenges listed above. In summary, Hejun is a truly outstanding early-career research scientist who already has made major contributions to the SEG community and undoubtedly will be a future leader in our field and a mentor to help teach and develop a new generation of exploration seismologists. The 2019 SEG J. Clarence Karcher Award is a very fitting recognition of his outstanding contributions.