A new study published in Geoscience Frontiers comes up with a surprising result.
From Science Daily.
FROM NEW YORK UNIVERSITY JUNE 20, 2021
Analysis of 260 million years of major geological events finds recurring clusters 27.5 million years apart.
Geological activity on Earth appears to follow a 27.5 million year cycle that gives the planet a “pulse,” according to a new study published in the journal Geoscience Frontiers.
“Many geologists believe that geological events are random over time. But our study provides statistical evidence of a common cycle, suggesting that these geological events are correlated, not random, ”said Michael Rampino, geologist and professor in the Department of Biology at New York University and lead author of the study.
Over the past five decades, researchers have suggested cycles of major geological events – including volcanic activity and mass extinctions on land and at sea – that range from about 26 to 36 million years ago. However, early work on these correlations in the geological records was hampered by limitations in the dating of geological events, which prevented scientists from conducting quantitative studies.
However, there have been significant improvements in radioisotopic dating techniques and changes in the geological timescale, resulting in new data on the timing of past events. Rampino and his colleagues compiled updated records of significant geological events over the past 260 million years using the latest available age-dating data and performed new analyzes.
NYU researchers found that global geological events are generally grouped at 10 different points in time over the 260 million years, grouped into peaks or pulses about 27.5 million years apart. Source: Rampino et al., Geoscience Frontiers
The team analyzed the age of 89 well-dated major geological events over the past 260 million years. These events include sea and land extinctions, large volcanic lava eruptions known as flood basalt eruptions, events when the oceans are depleted of oxygen, sea level fluctuations, and changes or rearrangements in the earth’s tectonic plates.
They found that these global geological events are generally grouped at 10 different points in time over the 260 million years, grouped into peaks or pulses spaced about 27.5 million years apart. The most recent accumulation of geological events was about 7 million years ago, suggesting that the next pulse of major geological activity is more than 20 million years in the future.
Here is a link to the original study
And the abstract.
abstract
We performed spectrum analyzes of the age of 89 well-dated major geological events over the past 260 million years from the recent geological literature. These events include times of marine and non-marine extinctions, major ocean anoxic events, continental flood basalt eruptions, sea level fluctuations, global pulses of intraplate magmatism, and times of changes in the rate of spread of the sea floor and plate reorganizations. The aggregate of all 89 events shows ten clusters in the last 260 Myr, arranged at an average interval of ~ 26.9 Myr, and Fourier analysis of the data reveals a spectral peak at 27.5 Myr with a confidence level of ≥ 96 %. A shorter period of ~ 8.9 Myr can also be important in modulating the timing of geological events. Our results suggest that global geological events are generally correlated and occur in pulses with an underlying cycle of ~ 27.5 Myr. These cyclical impulses of tectonics and climate change can be the result of geophysical processes related to the dynamics of plate tectonics and mantle plumes or, alternatively, they can be stimulated by astronomical cycles related to the movements of the earth in the solar system and in the galaxy.
Graphic summary
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