The detection of strange, unpredicted behavior deep below the surface near the San Andreas and San Jacinto faults suggests scientists have an incomplete understanding of the processes responsible for earthquakes in the region.
Over the past four decades, geoscientists have recorded thousands of small earthquakes in California's San Bernardino basin near the San Andreas and San Jacinto faults.
This previously undetected movement, dubbed "Deep creep," suggests things aren't happening beneath the San Andreas and San Jacinto faults in the ways we think they are.
Regions along these major faults are vulnerable to damaging earthquakes, the most recent being the 1989 Loma Prieta quake, which registered a magnitude 6.9, killed over 60 people, and caused upward of $6 billion in damages.
The San Andreas and San Jacinto faults are strike-slip faults, and their movement can be compared to two blocks sliding horizontally past one another.
So with no apparent creep going on below, scientists calculated the amount of load being placed onto the two primary faults by using data produced by the thousands of smaller quakes.
The findings of this study demonstrate that small earthquakes that occur adjacent to and between faults can have very different style of deformation than the large ground rupturing earthquakes produced along active faults.
https://gizmodo.com/something-unexpected-and-weird-is-happening-beneath-cal-1829177182
Over the past four decades, geoscientists have recorded thousands of small earthquakes in California's San Bernardino basin near the San Andreas and San Jacinto faults.
This previously undetected movement, dubbed "Deep creep," suggests things aren't happening beneath the San Andreas and San Jacinto faults in the ways we think they are.
Regions along these major faults are vulnerable to damaging earthquakes, the most recent being the 1989 Loma Prieta quake, which registered a magnitude 6.9, killed over 60 people, and caused upward of $6 billion in damages.
The San Andreas and San Jacinto faults are strike-slip faults, and their movement can be compared to two blocks sliding horizontally past one another.
So with no apparent creep going on below, scientists calculated the amount of load being placed onto the two primary faults by using data produced by the thousands of smaller quakes.
The findings of this study demonstrate that small earthquakes that occur adjacent to and between faults can have very different style of deformation than the large ground rupturing earthquakes produced along active faults.
https://gizmodo.com/something-unexpected-and-weird-is-happening-beneath-cal-1829177182
No comments:
Post a Comment