Seismic signals provided clues of a looming quake well before a destructive earthquake that struck Turkey this year, scientists have found. Photo: 123RF
Overseas research has found seismic signals provided clues of a looming quake well before a destructive earthquake that struck Turkey this year - and they may improve our ability to forecast future quakes.
"This is the first time that they've been able to observe that actual phenomena happening in the Earth crusts" - GNS Science seismologist Dr Matt Gerstenberger
Scientists found the unique signals were detected up to eight months before the 7.8 quake in February that caused widespread damage in southern Turkey and Syria, and claimed tens of thousands of lives.
Scientists simulating earthquakes in laboratories had previously observed that they were preceded by "predictable patterns of really tiny micro earthquakes", but such signals had never before been observed in the field, GNS Science seismologist Dr Matt Gerstenberger told Morning Report.
"This is the first time that they've been able to observe that actual phenomena happening in the Earth crusts."
Most seismically-active places around the world had seismic networks that were used to observe "the earthquakes that are happening all the time".
Scientists used the models created from those observations to provide long-term forecasts about where earthquakes were more likely to occur, Gerstenberger said, but they were less useful for short-term forecasting, with the exception of predicting things like aftershock sequences.
There was still a lot more to learn.
"It's one thing to know the big earthquake happened and look what happens prior to it, but it's a bit more difficult when they're happening in real time and to understand what's in the future."
But the new research would ultimately lead to improved seismic modelling, he said.
New Zealand's National Seismic Hazard Model (NSHM) used the same kind of "basic information" but on a "much coarser scale" than what had been observed in Turkey.
"As we have more observations like what they saw in Turkey then we'll be able to improve the models that we're currently using."