“Reading the trackways of tectonic faults” by 2023 W.W. Hutchison Medalist, Dr. Jamie Kirkpatrick

Abstract: When rocks slide past each other in tectonic faults they produce grooved and striated surfaces that create an archive of the movement, similar to bedrock striations that form under a glacier. In faults, these surfaces are called slickensides and the grooves are called slickenlines. They are trackways that record not only the direction of fault movements in the geologic past, but also record the deformation processes and conditions active on a fault plane during slip at depth in the crust. In this talk, I will explore how information can be extracted from the geometry of slickensides that allows us to investigate both fault strength and the physics of earthquake ruptures. I will present field observations of exposures of ancient, exhumed faults from the deserts of the western USA and modern plate boundaries including the subduction megathrust offshore of Costa Rica. This work reveals that there are aspects of the geometry of fault slickensides that are common to faults in all tectonic settings and rock types, and which control both the long-term strength of the faults as well as the characteristics of the earthquakes they host.

Dr. Jamie Kirkpatrick is a young structural geologist at McGill University who has made exceptional advances to our understanding of faults, fault rocks and earthquakes in recent years. His contributions are worthy of recognition by the GAC and the W.W. Hutchison Medal. Jamie is a courageous researcher who breaks new ground by tackling long-standing difficult problems in creative new ways. His recent work on the rheology of fault rocks, the geometry of fault surfaces, and criteria for recognizing ancient fault rocks in the rock record represents an enormous contribution with many practical applications. His research is rigorous with attention to detail. Jamie combines quantitative theoretical research with field studies in critical settings to produce results that can be applied directly to real rock.

The results of his research have direct implications for investigations as diverse as earthquake hazard mitigation, structural and tectonic field analysis, and exploration for orogenic gold deposits. Canadian Earth scientists in a variety of subdisciplines benefit from the advances made by Jamie’s research. He has a well-funded research program that has resulted in a large number of publications and conference presentations. He has taught and supervised student research at the doctoral, masters and undergraduate level, and knows how to share results and generate excitement about research with a diverse audience. Jamie is an international leader in the earthquake science community and is pioneering the application of field observation and structural geology techniques to problems in tectonics, faults and shear zones. His advancement of quantitative methods and instrumentation applied to classic problems of understanding stress and strain is impressive and his effectiveness as a communicator and educator is ensuring that the geoscientists of tomorrow are well-prepared to address pressing societal issues. Jamie is rapidly establishing himself as one of the bright young lights in the fields of earthquake science and structural geology.