image: Francisco José Sánchez-Sesma
Credit: Courtesy of Francisco José Sánchez-Sesma
SSA and the Earthquake Engineering Research Institute (EERI) are pleased to announce that Francisco José Sánchez-Sesma, professor at the Universidad Autónoma de Mexico (UNAM), is the 2026 recipient of the William B. Joyner Lecture Award.
Sánchez-Sesma will deliver the Joyner Lecture at the 2026 SSA Annual Meeting to be held 14-18 April 2026 in Pasadena, California and the 13th National Conference on Earthquake Engineering (13NCEE) to be held 13-17 July 2026 in Portland, Oregon.
His Joyner Lecture, "Seismic Wave Propagation in Complex Geological Domains: From Site Effects in Ground Motion to Diffuse Fields in Passive Seismology," will reflect on decades of research aimed at understanding and modeling seismic wave propagation in complex geological media and its manifestations in ground motion, from strong shaking during large earthquakes to weak ambient vibrations such as microtremors and seismic noise.
These efforts integrate the analysis of recorded data with analytical and numerical modeling, including geometric representations to capture the complexity of the resultant wavefield, said Sánchez-Sesma.
“These experiences highlight the value of integrating theoretical rigor, numerical modeling, and empirical observation to advance our understanding of seismic wave phenomena. As we move forward, the challenge—and opportunity—lies in extending these insights to the complex, multiscale problems of modern seismology through physics-based and data-driven approaches,” said Sánchez-Sesma. “This continued effort honors the Joyner vision of bridging the gap between seismologists and engineers in pursuit of an earthquake-resilient society.”
The lectureship is jointly awarded by EERI and SSA to those who have provided outstanding earth science contributions to the theory and practice of earthquake engineering or outstanding earthquake engineering contributions to the direction and focus of earth science research—together with demonstrated skills of communication at the interface of earthquake science and earthquake engineering.
The lecture honors the distinguished career of William B. Joyner at the U.S. Geological Survey and his abiding commitment to continuing communication and education at the interface between research findings of earthquake science and the practical realities of earthquake engineering.
Sánchez-Sesma’s contributions to theory and method throughout his career have made a significant impact on seismic hazard assessment in earthquake engineering, aided by his early background as a structural engineer. He is best known for his contributions to methods, such as the Indirect Boundary Element Method (IBEM), for studying seismic wave propagation, especially amplification of seismic waves by complex 3D surface geological structures.
His encounters with Bessel functions and with Quantitative Seismology, the influential 1980 book by Keiiti Aki and Paul Richards, “provided tools and a rigorous framework to understand reflection, transmission, and diffraction, concepts of waves that initially seemed almost magical, said Sánchez-Sesma. “Building on Green’s functions as fundamental solutions, we developed integral formulations to model wave propagation in irregular media” that became IBEM.
Sánchez-Sesma’s mastery of mathematical formulations, his development of new techniques of numerical simulations of wave propagation and techniques for data processing for seismic imaging were noted in his nomination for the Joyner award.
Beyond his numerous contributions to the global practice of seismology and earthquake engineering, Sánchez-Sesma has demonstrated significant science and engineering leadership throughout Latin America.
“A key motivation came after the devastating 1985 [Mw 8.1] Michoacán earthquake, which caused catastrophic damage in Mexico City,” he explained. “Under the guidance of Emilio Rosenblueth, Luis Esteva and others, we employed the reformulated Random Vibration Theory by David M. Boore to analyze ground motion. This effort directly informed the Mexico City new building code, which, for the first time, incorporated Fourier spectrum as a central design concept.”
The new building code has protected thousands of lives in subsequent events such as the Mw 7.1 2017 Puebla-Morelos earthquake.
The Carnegie Institution of New York appointed Sánchez-Sesma to serve from 2017 to 2019 as a member of the Working Group of the Inter Academy Partnership for the UN agenda 2030. He was the only member from the Latin American region.
Among his notable positions, Sánchez-Sesma served as president of the Mexican Society of Earthquake Engineering from 2001 to 2003 and was the president of the Mexican Academy of Engineering from 2004 to 2006.
He received his BSc in civil engineering in 1974 and his MSc (1975) and Ph.D. (1979) in structural engineering from UNAM.