For the last fifty years, researchers have suspected that important geological events on our planet occur in a cycle, but data to accurately support this were not available. However, with the rapid development of technology, geologists were able to show that the Earth actually had a pulsating geological pulse, although they could not determine why.
New York University and Carnegie Institution for Science researchers analyzed the ages of 89 major geological events that occurred over the past 260 million years, including marine and terrestrial mass extinctions, sea level fluctuations, and tectonic plate shifts, in the hope of uncovering a cyclical pattern.
As a result of this research, they managed to find a cycle. Using a mathematical technique called Fourier analysis, they discovered that the events were clustered at 10 different time points over a 260 million year span. This means that there is a “pulse” of major geological activity approximately every 27.5 million years.
“Many geologists believe that geological events occur randomly over time,” said Michael Rampino, lead author of the study. “But our study provides statistical evidence for a common cycle and shows that these geological events are not random but interrelated.”
The next step will be to figure out the cause of this cycle. The authors point to research suggesting that linked cycles of global tectonics and climate change may play a role. In a study published this month, two of the researchers examine this possibility in more detail, as well as a possible connection to astronomical cycles both in the Solar System and at broader astronomical levels.
“Whatever the origins of these cyclical events, our findings largely support the existence of periodic, coordinated, and intermittently cataclysmic geological records,” Rampino said. “This is different from the views of many geologists,” he says.
Fortunately, you don’t have to worry about the next big spike in the cycle. The last cluster of events occurred approximately 7 million years ago. So, Earth’s next major series of events is expected to be about 20 million years in the future.
The study was published in Geoscience Frontiers.