New research shows that a big earthquake can not only cause other quakes, but large ones, and on the opposite side of the Earth.
The findings, published today in Scientific Reports, are an important step toward improved short-term earthquake forecasting and risk assessment.
Scientists at Oregon State University looked at 44 years of seismic data and found clear evidence that temblors of magnitude 6.5 or larger trigger other quakes of magnitude 5.0 or larger.
It had been thought that aftershocks — smaller magnitude quakes that occur in the same region as the initial quake as the surrounding crust adjusts after the fault perturbation — were the only seismic activity an earthquake could lead to.
But the OSU analysis of seismic data from 1973 through 2016 — an analysis that excluded data from aftershock zones — provided the first discernible evidence that in the three days following one large quake, other earthquakes were more likely to occur.
