Laura J. Pyrak-Nolte

Laura J. Pyrak-Nolte

PhD	Rock Mechanics
PhD university	University of California at Berkeley

Laura J. Pyrak-Nolte developed a fluid flow versus elastic stiffness function that is an important contribution, as it provides a fundamental relation between two important and often-measured properties.

The 2020 SEG Reginald Fessenden Award

by Charles Fairhurst

Laura J. Pyrak-Nolte developed a fluid flow versus elastic stiffness function that is an important contribution, as it provides a fundamental relation between two important and often-measured properties. This relation, coupled with knowledge of fracture surface properties, provides a promising approach for inferring fluid flow properties from seismic data in fractured rock. Pyrak-Nolte has made other important contributions to rock physics, including identification of precursory signatures to failure in geophysical signals.

Biography Citation for the 2020 SEG Reginald Fessenden Award

The function for which this Reginald Fessenden award is made to Laura Pyrak-Nolte is a major result of the dedicated research that Laura, together with her colleagues and students, led over the past three decades.

Laura is currently distinguished professor of physics and astronomy at Purdue University. She obtained her PhD in rock mechanics in 1988 from the University of California, Berkeley. Her adviser was the renowned (late) professor Neville Cook at the University of California, Berkeley.

The topic of her thesis “Seismic Visibility of Fractures” is now a field that she has developed into a potentially major component of rock mechanics/ engineering and in which she is now internationally pre- eminent. Her International Society for Rock Mechanics and Rock Engineering (ISRM) online lecture of March 2018, “Geophysical Characterization of Fractures,” (https://www.isrm.net/gca/index.php?id=1331) provides an excellent overview of Laura’s research over the last three decades. (Of the 30 lecturers invited by ISRM to date, Laura is the only woman.)

Laura is in demand as an expert adviser (e.g., to the U.S. Department of Energy’s Office of Basic Energy Sciences) and lecturer in the United States and internationally. Elected a fellow of the American Rock Mechanics Association in 2013, she served as ARMA president from 2017 to 2019 and is currently president of the International Society for Porous Media (InterPore) (2019–2021) ISRM was established in 1962 by Leopold Müller to draw international attention to the central importance of discontinuities, especially on the scale of engineering projects, on the deformation and failure of the rock. Müller had stressed his concern for years, but it was the collapse of the Malpasset Dam in France in December 1958 (423 deaths) and Italy’s Vaiont Dam disaster in October 1963 (1917 deaths) — where Müller was the geotechnical consultant — that helped precipitate his ISRM action. In both cases, these failures were the result of sliding along major joints as the fluid pressure in the joint increased during filling of the dam The fluid has a “buoyant” effect of reducing the effective normal stress (σn – p) [σn = normal stress; p = fluid pressure] at any point in the rock. Many major engineering activities associated with climate change, sustainability, infrastructure renewal, etc. involve this effect of fluid pressure in rock — geothermal energy, CO2 sequestration, waste isolation, dam foundations, rock slope stability, borehole extraction of mineral resources, aquifer management, and more.

Laura’s research is a valuable complement to other ongoing developments with respect to the behavior of discontinuities in rock, such as Discrete Fracture Network (DFN) and Synthetic Rock Mass (SRM) analysis. Advances in computer modeling procedures, such as message passing interface, or MPI, will also contribute. The U.S. Department of Energy has identified adaptive control of subsurface fractures, reactions, and flow as a Grand Challenge and has recently awarded $140 million to the University of Utah to develop the Frontier Observatory for Research in Geothermal Energy project over five years (2019–2024)

Thus, the stage appears set for the benefits of Laura’s research to be tested in practical application in the United States. This is likely to require a large team of colleagues — and significantly increased levels of federal research funding. In this way, Laura Pyrak-Nolte may be able to complete the goal of her decades of research — to improve engineering design, and safety, of projects in discontinuous rock.