Fault2SHA Learning Series – Coulomb Stress Transfer by Ross Stein

Earthquakes Converse by the Transfer of Stress

Ross S. Stein

Cofounder and CEO, Temblor, Inc., Adjunct Professor of Geophysics, Stanford University, Former Senior Scientist, U.S. Geological Survey

Monday 12th April 2021 15:00 Central European Time

I will argue that large earthquakes can promote and inhibit failure on nearby faults, and that the transfer of Coulomb stress plays a governing—but not exclusive—role in this interaction. Through a series of physical demonstrations and animations, I will use these concepts to explain the distribution of mainshocks, aftershocks and progressive earthquake sequences in a number of cases around the world.

In this talk, I will be conveying work of my spectacular collaborators, Geoffrey King, Shinji Toda, Jian Lin, Tom Parsons, Jim Dieterich, Keith Richards-Dinger, Aykut Barka, and Volkan Sevilgen, as this has always been a team effort, bringing together a range of insights and skills.

At heart, we find that the stress imparted by earthquakes does not simply turn seismicity on or off; rather, the background seismicity rate is enhanced by stress increases, and suppressed by stress decreases. This, we believe, best explains why seismicity in stress trigger zones is often patchy or discontinuous; why seismicity rate declines in stress shadows can be subtle or absent, and why some aftershock zones expand, migrate or densify over time, and why some aftershocks last for years and others persist for centuries.

While this model is a far cry from an earthquake prediction, it perhaps can take us on the road to the more useful and accurate earthquake forecasts that we all seek.

Image from Stein (2003)

Youtube link for those of you who missed the session (or if you want to watch again)

Fault2SHA Learning Series – Fault displacement hazard by Paolo Boncio

Fault displacement hazard – a geological perspective

Paolo Boncio

Associate Professor, DiSPUTer Department, Università degli Studi G. d’Annunzio Chieti e Pescara, Chieti, Italy

Monday 8th March 2021, 15:00 Central European Time

Fault displacement hazard (FDH) is a localized hazard due to rupture of the ground surface from slip along an earthquake fault (and fault creep). This might offset, tilt, warp and damage buildings and facilities sited across or in the vicinity of the fault trace. FDH is particularly relevant for distributed infrastructures (e.g., lifelines) and critical facilities (nuclear facilities, dams, etc.).

The seminar will focus on coseismic (not creep) FDH, in particular on 1) basic concepts, definitions, controlling factors, scale of the problem; 2) mitigation strategies based on zoning and avoidance, regulated by specific rules or guide lines; and 3) poorly known, developing methodologies based on probabilistic approaches, with examples from the globe and from Italy.

If you missed the seminar, you can watch on youtube:

https://www.youtube.com/watch?v=Qlpl8Znx8Ac

5th Fault2SHA Workshop

All Hands on Deck: Promoting Faults in Seismic Hazard Assessment

Thursday 12th November, Friday 13th November, Wednesday 2nd December

Online in the afternoons (times based on CET, Central European Time)

The third day Wednesday 2nd December 2020 will be an open discussion among participants bringing together the former experience and new initiatives from the first two days of the workshop with the aim of looking at what next for Fault2SHA.

How can we collaborate in the future bringing together our different expertise, experience and questions? What new laboratories can we form? How can the ExCom help with this? 

If you have not said already, please let us know whether you will be attending HERE

This session will NOT be available on YouTube

General info and the full programme HERE