The places that are not at risk from earthquakes are inhospitable.
Likely not the primary takeaway intended by Professor Richard Walker during his talk on earthquake hazards and risks in continental interiors, but it was definitely one I took away from this wide-ranging and instructive talk that included foundations of earthquake science and the challenge of increasing resilience in a space where prediction is still looking for its feet.
Professor Walker brought us with him on a tour of a number of historical earthquakes, their unremitting horror, and what we can take away from them for the future. What can be done to identify zones of hazard and how can this information reduce the risk?
A careful exploration of the earthquake record over an appropriately long time can be instructive in identifying where future hazards can strike. Why did an earthquake strike under Bam in Iran in 2003? Why is the town there? Why have areas with high tectonic activity stayed populated despite the uncertainty of disasters? What can we look out for in the present to understand earthquake risk?
These questions have come up frequently in recent earthquakes. Coming from Pakistan, these were bandied about following the 2005 Kashmir earthquake (magnitude 7.6, and a maximum Mercalli intensity of ‘Extreme’ at XI), with a death toll exceeding 70,000. Victim blaming for ‘choosing’ to live in dangerous locations? Professor Walker presented some excellent examples of how the existence of faults (boundaries between tectonic plates where earthquakes happen) and the underlying geology that creates and enhances the earthquake risk is also responsible for creating conditions conducive for human settlements. Faults can create hydrological environments that can allow for water extraction and application for residential and agricultural use. They can also leave behind indications in the landscape for future earthquakes. Little hills near and within human settlements are raised by active faults and can point to a history (and a future) of earthquakes.
So, settlements in earthquake-prone areas are there for a reason. But what can we do now for mitigating the risk and bouncing back to normal once they hit? Mitigation is hard in the best of times and places, but is much harder in some areas because of a lack of resources, political will, and because preparedness tends not to be terribly urgent and high priority. Research and implementation efforts exist that focus on understanding the hazards themselves, developing pathways to resilience and fostering networks of research exchange. But, a much longer and committed view and path is needed where attention is not diverted by other urgent and pressing needs. There are learnings from research, history, and earthquake and hazard cultures around the world that can be adapted and integrated for improved resilience. While human resilience goes a long way, it needs much help when facing disasters at a deep planetary scale.
The challenges are pressing, deeply uneven across humanity, and on a geologic deep time scale. But they are not insurmountable.
