A renewed search for earthquake precursors

The past 20 years have seen renewed interest in the detection of potential earthquake precursors from scientists at the University of Tokyo, Université Joseph Fourier, Berkeley, University of Hokkaido, Stanford, Australian National University, the US Geological Survey and the Carnegie Institution. Remarkably these studies haven’t been marked by overhyped press releases, but rather the gradual reporting of diverse earth behaviors that have putatively been observed prior to some large earthquakes.

This search is nothing new and countless earthquake precursors candidates have been proposed. Most of these have been resigned as post-hoc explanations…at best. But the search has continued because lurking behind all of these works is the idea that if the precursory observations were to robustly generalize this would move us forward along the path towards earthquake prediction. Over the past decade possible pre-earthquake correlative observations spanning the solid and fluid earth systems have included:

• Atmospheric pressure from storms (Liu et al., 2009)
• Ionospheric behavior (Heki, 2011; Heki and Enomoto, 2013)
• Transient crustal motion (Mavrommatis et al., 2015)
• River water chemistry (Ingebritsen and Manga, 2014)
• Earthquake rates (Bouchon et al., 2011)
• Earthquake faulting styles (Lister et al., 2018)
• Solid earth tides (Ide et al., 2016)
• Snowmelt (Montgomery-Brown et al., 2019)

In all of these cases, the sample sizes are small…really, really, really small…like 1-3 events. We can definitely do better than that and we need to. There’s now near continuous reporting of high-quality data at global scale…and tons of it. I’m not sure what’ll happen but it’s exciting to renewed interest in the must fundamental and important of all earthquake science problems.