Geologists think that a big earthquake along the San Andreas Fault is long overdue. California should have had a major earthquake by now but nothing has happened. 

The fear for the “Big One”, an earthquake with a magnitude of 8 or greater, however, has reignited following the twin earthquakes that occurred in California this weekend. 

The 6.4 and 7.1 magnitudes quakes were the largest to occur in the state in two decades. The US Geological Survey (USGS) warned that more big earthquakes, more powerful than those that occurred in the past few days, could possibly happen. 

“(These quakes do) not make (the Big One) less likely,” local seismologist Lucy Jones said. “There is about a one in 20 chance that this location will be having an even bigger earthquake in the next few days, that we have not yet seen the biggest earthquake of the sequence.”

Amid the possibility of stronger earthquakes shaking California, some people started to fear of another dangerous event: an eruption of a supervolcano. After the two quakes that rocked California last week, there was a spike in internet searches for “Yellowstone volcano” and “Yellowstone caldera”. 

Fears loom that a strong earthquake like the Big One could trigger the eruption of the Yellowstone supervolcano. This event can bury large portions of land in harmful volcanic ash killing plants and animals, even endangering human lives. 

Yellowstone National Park Yellowstone National Park Photo: Reuters

Scientists, however, say these fears are unfounded. Writing on the Yellowstone Volcano Observatory website, scientist Mike Poland explained why the earthquakes in California will not cause the eruption of Yellowstone.

He said that the last time the Yellowstone erupted was 70,000 years ago and over thousands of years after the explosion, there may have been more than 7,000 strong earthquakes, but none led to the eruption of Yellowstone. 

Poland acknowledged that quakes may still have an impact on volcanoes, such as trigger microearthquakes, but these could not cause eruptions. 

“Earthquakes like those of the past week are unlikely to trigger volcanic eruptions, although they might trigger microearthquakes at some volcanoes,” Poland wrote. “Yellowstone has not erupted in 70,000 years, and that was a lava flow, not an explosive eruption. That means there might have been something like 7000 M7+ earthquakes in that time period. None caused Yellowstone to erupt.”