The California earthquakes silently rocked the US state between 2008 and 2017. Geologists at the California Institute of Technology (CALTECH) trawled through 10 years worth of seismic data to pinpoint the new tremors. The incredible earthquake discovery has expanded South California's catalog of known quakes from 180,000 to an astounding 1.8 million. Caltech's geologists published their findings on April 18 in the peer-reviewed journal Science.
Zachary Ross, the study's lead author, said: "It's not true that the small earthquakes were occurring."
The California earthquakes were numerous but relatively week – between magnitude 1.7 and -2.0.
According to the US Geological Survey (USGS), any tremor
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The earthquakes were so small, they
The earthquake across Southern California are much more frequent than previous thought.
Until now, an earthquake was estimated to eru
With the 1
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This, in turn, translates to about 495 earthquakes in Southern California every single day.
In order to detect the minor tremors, the geologists used a technique known as template matching.
Caltech explained in a statement: "To overcome the low signal-to-noise ratio, the team turned to a technique known as 'template matching', in which larger and more easily identifiable earthquakes are used as templates
"When a student chooses to record his or her own data, he or she is scanned by a local seismometer
Scientists are now positive the discoveries will help institutions like the USGS better prepare for and detect earthquakes.
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According to the USGS, California is the leading US state in terms of damage sustained by frequent earthquakes.
The geological agency said, "It's well known that California, the Pacific Northwest and Alaska have a lot of earthquakes, some of which are quite damaging.
"It's well known that California, the Pacific Northwest and Alaska have a lot of earthquakes, some of which are quite damaging.
" Some areas of the country are more at risk than othe rs, but, in fact, 42 of the 50 states could damaging ground shake from an earthquake in 50 years and 16 states have a relatively high likelihood of experiencing damaging ground shaking. "