Surface fault rupture during the 2023 Türkiye earthquakes: Implications for earthquake engineering research and practice

H. Benjamin Mason, PhD, PE

Research Civil Engineer, U.S. Geological Survey

Associate Professor, Oregon State University

February 20, 2024 | 1 p.m. | 140 Ketter Hall

On 6 February 2023, two damaging earthquakes – a MW 7.8 mainshock and a MW 7.5 aftershock – occurred in south-central Türkiye in the province of Kahramanmaraş. The MW 7.8 mainshock and MW 7.5 aftershock caused surface fault rupture along the East Anatolian and Narlı faults as well as the Çardak fault, respectively. Following a satellite-based fault rupture reconnaissance effort, I performed ten days of field work near the intersection of the East Anatolian and Narlı faults with collaborators. The field work consisted of line mapping of fault rupture not easily observed by satellite-based or drone-based surveys as well as fault displacement measurements. In this talk, I will give an overview of the surface fault rupture, provide details about the field aims, methods, and observations, compare the collected field data to predictions made by fault displacement models, reflect on how the collected field data show weaknesses in current fault displacement models and how the models can be improved, provide guidance for performing post-earthquake reconnaissance considering surface fault rupture, and talk about research and practical implications. In particular, I will focus on the implications for: 1) researchers and practitioners investigating lifelines crossing active faults, 2) researchers forwarding probabilistic fault displacement hazard analyses, and 3) earthquake geologists estimating fault displacement measurement uncertainty. Finally, I will talk about how the collected field data will shape my own near-term research vision.

Henry Benjamin (Ben) Mason is a research civil engineer at the U. S. Geological Survey’s Geologic Hazards Science Center in Golden, Colorado, an associate professor at Oregon State University’s College of Engineering, and a licensed professional engineer in the State of Colorado. Ben’s research interests center around soil-fluid-structure interaction, and the relevant sub-interactions, during natural hazards, and he uses analytical, numerical, and physical modeling techniques to pursue his research interests. He has also participated in six post-earthquake reconnaissance trips, which have shaped his research vision. Ben earned PhD and MS degrees in Civil and Environmental Engineering from the University of California at Berkeley and a BS in Civil Engineering from the Georgia Institute of Technology.