The San Andreas Fault line is one of America’s most infamous and dangerous earthquake risk areas as movies have been made about the fault line and researchers have studied it extensively.
According to researchers from the University of Hawaii, GPS mapping of the fault line may give researchers a tip as to when the fault is ready to rupture.
The results were announced in Monday’s Nature Geoscience journal.
The fault, which runs along the Pacific coast in Northern California, through the Bay Area and into Southern California, has been the spot for many of America’s most devastating earthquakes. Infamous quakes that took place near the fault include the devastating 1906 Great San Francisco earthquake and the 1989 Loma Prieta quake that also devastated the Bay Area.
Looking at the vertical motion of the fault, scientists were able to key in on the movement of the earth while blocking out other environmental factors.
“While the San Andreas GPS data has been publicly available for more than a decade, the vertical component of the measurements had largely been ignored in tectonic investigations because of difficulties in interpreting the noisy data,” said lead researcher Samuel Howell. “Using this technique, we were able to break down the noisy signals to isolate a simple vertical motion pattern that curiously straddled the San Andreas fault.”
The researchers said they discovered 125 mile-wide “lobes” of uplift and subsidence, with a few millimeters of motion each year, straddling the fault. The researchers added that this GPS evidence confirmed their earlier prediction.
The GPS vertical motion measurements, researchers said, will allow scientists to better understand the structure and behavior of faults.