Why is the planet being struck by so many large earthquakes?

According to the USGS, the number of large magnitude earthquakes striking the planet doubled in 2014. The USGS is quite certain about the data but it is uncertain about the cause. 

April 2016 – GEOLOGY – Seismic tension continues to mount in the volatile region of the planet known as the Ring of Fire, where more than 90% of the world’s earthquakes occur, and more than 81% of the largest magnitude earthquakes occur. The extraordinary and precipitous rise in the number of large magnitude earthquakes is both astounding and alarming. On average, only about fifteen 7+ magnitude earthquakes strike the planet each year. We’ve had 2 such earthquake in less than 72 hours.

This has continued to baffle many of the world’s leading geologists, who still attest the rise in the number of large earthquakes is merely a random natural occurrence. For instance, the number of large earthquakes doubled in 2014. However, here’s what scientists had to say about it: “If you think there have been more earthquakes than usual this year, you’re right. A new study finds there were more than twice as many big earthquakes in the first quarter of 2014 as compared with the average since 1979.

“We have recently experienced a period that has had one of the highest rates of great earthquakes ever recorded,” said lead study author Tom Parsons, a research geophysicist with the U.S. Geological Survey (USGS) in Menlo Park, California. But even though the global earthquake rate is on the rise, the number of quakes can still be explained by random chance, said Parsons and co-author Eric Geist, also a USGS researcher. Their findings were published online June 21 in the journal Geophysical Research Letters. ¹

The average rate of big earthquakes — those larger than magnitude 7 — has been 10 per year since 1979, the study reports. That rate rose to 12.5 per year starting in 1992, and then jumped to 16.7 per year starting in 2010 — a 65 percent increase compared to the rate since 1979. This increase accelerated in the first three months of 2014 to more than double the average since 1979, the researchers went on to report.

Why is our planet having so many big earthquakes? It’s because big geological processes are driving the reactive seismic forces that create earthquakes along faults, trenches, and the planet’s many subduction zones. We don’t live on a perfect sphere. We live on a planet that more resembles a cracked egg. Cracked and badly fractured, partially due to its geology but mainly due to the intense heat rumbling within its interior (about 6,000 C and 10,800 F) and the geological dissipative features that try to regulate that heat and resulting kinetic energy. These geologic features include mantle plumes, faults, tectonic plates, submarine vents, and volcanic systems.  

In the last 24 hours, moderate earthquakes have struck regions in the far Pacific like Fiji and Tonga, while smaller earthquakes have rattled portions of Japan, Ecuador, Guatemala, El Salvador, Chile, Alaska, California, Indonesia, Puerto Rico and the Virgin Islands, the Adriatic Sea, the Strait of Gibraltar, the Hawaiian Islands, and Greece. Ecuador was struck with a 7.8 magnitude earthquake. Ecuador’s antipodal point is the Sumatra region of Indonesia – which was struck with 5.0,  4.8, and 4.5 magnitude earthquakes in the last 24 hours. You might say the entire planet is now reeling from earthquakes from one end to the other. Where will the next big earthquake strike or how long will this current seismic episode last is anybody’s guess? About the only thing we can be certain of is there will be many more such events and they will increase in both severity and intensity. –Alvin Conway, TEP

1. Live Science