Parkfield in California is no stranger to an earthquake – it sits on the
To do so, the team looked at seismic wave data leading up to the last, late quake back in 2004; thankfully, researchers have taken a keen interest in studying activity in the region since the 1980s.
It helped that, as the study authors write, the Parkfield region has “very simple geometry and behavior” and is known to be a transitional segment, sitting between a part of the fault where plates can move against each other (“creeping”) and a part where they can’t (“locked”).
Specifically, the team was looking for any patterns or clues in how the seismic waves caused by a quake lose energy as they travel through the Earth’s crust in this transitional region; this is called attenuation.
And they appear to have found one – in the six weeks leading up to the 2004 earthquake, the loss of energy in low-frequency seismic waves increased, while decreasing for high-frequency waves. Known as bifurcation, according to the authors, this likely reflects what’s going on underneath the surface just before an
But the real question is, will these measurements allow scientists to predict when the next earthquake will be? And could the same methods then be applied to other
If you’re hoping for an answer to those questions now, then we’re afraid you’re going to have to wait. The researchers won’t truly know if these measurements are a sign until the next earthquake happens.
You might not have to wait long though; study author Luca Malagnini told
That being said, Malagnini and colleagues write that they “cannot find signs about the Parkfield asperity having reached its critical state yet”, so at the very least, it’s probably more than six weeks away.
The study is published in
[H/T: