Johnson’s ‘San Andreas’ blockbuster might have done more than keep people awestruck in the face of supersized natural disasters.
Scientists across the U.S. are debating on the accuracy of the fiction scenario that kept people locked to their seats as they watched havoc engulf San Francisco in the aftermath of a catastrophic quake and tsunamis rolling out over the city.
While the San Andreas Fault does pose a real danger, geologists debunk the idea that it could provoke an earthquake the magnitude of that showcased in the movie.
However, things seem to be a little different when talking about the real danger of a tsunami occurring on the Californian coastline.
A new recently published study, authored by geologist Mark Legg draws the lines of the real-life threats hidden in the little-known seafloor faults of Southern California. According to the study, both Los Angeles and San Diego could be significantly affected by the giant crushing waves.
Mark Legg extensively discussed the seafloor faults of Southern California, as well as Northern Baja and how they might act to bring about quakes of 8.0 magnitude, prompting the seafloor to rise and create the much feared tsunamis.
Legg’s study is much welcome both because it scientifically explains what a real-life scenarios would imply and due to the fact that it dispels some of the fears sparked by the blockbuster.
Neither a tsunami nor a quake would ever reach the magnitudes presented in ‘San Andreas’, yet some attention should be invested in the California Continental Borderland. The under-sea faults present there, due to the subduction zone created between the Pacific and the North American tectonic plates are capable of enabling 8.0 magnitude quakes.
Legg’s research pooled data from a 2010 depth survey covering 2,800 miles in fault lines, emphasizing especially the Santa-Cruz Catalina Ridge Fault and the Ferrelo Fault. In these areas, the seafloor is susceptible to forces that create both horizontal movement and vertical compression. These can create the 8.0 magnitude quakes according to computer modelling.
Another area that deserves attention is the Cascadia subduction zone, bordered by Northern California, Washington and Oregon states. The results of computer models place these areas in a high-risk zone that would also be subjected to the impact of tsunamis.
When talking tsunamis, Legg argues that people should not imagine the magnitude of those hitting the coast of Japan in 2011. At most, a two meter wave would threaten San Diego and Los Angeles, without much damage being implied.
The real problem is that there are not many warning signs or warning systems in place at the moment. In these situations were realtime response should be the priority, there is little chance of issuing alarm signals in time.
From this perspective, the study argues for more funding dedicated to the careful analysis of California faults, be they underwater or land, and quicker response systems.
A more detailed account of what we could really be facing in case of activation of seafloor faults on the California coastline can be found in the Journal of Geophysical Research, where Mark Legg’s study was published.
Image Source: NBCnews