Experts at the Southern California Earthquake Center have released data on a growing seismic threat. These are supershear earthquakes, which occur when a fault in the earth's crust propagates faster than the speed of seismic waves, creating a double-whammy effect—first a sharp jolt from the shock wave, followed by powerful vibrations from the overtaking waves.
Professor Yehuda Ben-Zion, who led the research, emphasizes that about a third of the world's major strike-slip earthquakes fall into this category, yet their danger has been systematically underestimated.
The concentration of such faults in close proximity to California's metropolitan areas poses catastrophic risks to buildings and critical infrastructure designed to outdated standards. Current building codes were developed without taking into account the specific nature of supershear earthquakes, which direct destructive energy along the fault line rather than perpendicular to it.
Researchers urge immediate increased monitoring of active fault zones and extensive computer modeling. They predict that California will inevitably experience several earthquakes exceeding magnitude 7 in the coming decades, and the only defense against disaster will be proactive enforcement of building codes.