Analysis of 260 million years of major geological events has yielded recurring clusters separated by 27.5 million years , giving our planet a “pulse” – a 27.5 million-year cycle of geological activity.
“Many geologists believe that geological events are random over time. But our study provides statistical evidence for a common cycle, suggesting that these geological events are correlated and not random,” says Michael Rampino, geologist and professor of the New York University Department of Biology and leader of the study that publishes the journal Geoscience Frontiers.
Over the past five decades, researchers have proposed cycles of key geological events, including volcanic activity and mass extinctions on land and at sea, ranging from approximately 26 to 36 million years. But this analysis in the geological record was hampered by limitations in the age dating of geological events , which prevented scientists from conducting quantitative research.
Advancement in technology
Fortunately, significant improvements in radioisotope dating techniques and changes in the geological time scale have allowed new data on the timing of past events to be obtained much more reliable than previous ones.
Thus, using the latest available age dating data, the experts compiled up-to-date records of major geological events over the past 260 million years and conducted further analyzes. The team analyzed the ages of 89 well-dated major geological events, such as extinctions, both marine and terrestrial, major volcanic lava spills, events in which the oceans ran out of oxygen, sea level fluctuations, and changes or reorganization in plates. tectonics of the Earth, for example.
The researchers found that these global geological events generally cluster in 10 different time enclaves over the 260 million years, grouped into peaks or pulses about 27.5 million years apart.
When will the next pulse take place?
The most recent cluster of geologic events occurred about 7 million years ago, suggesting that the next pulse of geologic activity will be about 20 million years from now.
The authors postulate that these pulses may be a function of cycles of activity in the Earth’s interior : geophysical processes related to the dynamics of plate tectonics and climate. Although of course, they could also be setting the pace of these events similar cycles in the orbit of the Earth in space.
“Whatever the origin of these cyclical episodes, their occurrences support the case for a largely periodic, coordinated, intermittently catastrophic geological record, which is quite different from the views of most geologists,” Rampino notes.
Referencia: Michael R. Rampino et al. 2021. A pulse of the Earth: A 27.5-Myr underlying cycle in coordinated geological events over the last 260 Myr. Geoscience Frontiers 12 (6): 101245; doi: 10.1016/j.gsf.2021.101245
