麻豆淫院

A new international study in Earth and Planetary Science Letters reveals that the boundaries between geological epochs and periods, even though randomly distributed, follow a hidden, hierarchical pattern. Co-authored by Prof. Andrej Spiridonov from Vilnius University (VU) Faculty of Chemistry and Geosciences, the research shows that these time boundaries cluster in a way that reflects Earth's system's deepest fluctuations. This finding could reshape how we understand our planet's past and its possible futures.

"Geological time scales may look like tidy timelines in textbooks, but their boundaries tell a much more chaotic story. Our findings show that what seemed like uneven noise is actually a key to understanding how our planet changes, and how far that change can go," says Prof. Spiridonov, geologist and paleontologist, and a co-author of the study.

A global team decoding planetary rhythms

The study was carried out by an international group of researchers: Prof. Shaun Lovejoy and Rhisiart Davies from McGill University (Canada), Assoc. Prof. Fabrice Lambert from the Pontifical Catholic University of Chile, Raphael Hebert from the Alfred Wegener Institute (Germany), and Prof. Spiridonov from VU (Lithuania).

Their research focused on the distribution of boundaries that define epochs, periods and eras in geological time. These include the official International Geochronological Chart as well as biozone-based time scales used temporal ranges of extinct species such as conodonts, graptolites and ammonoids. Across all of these timelines, from local to global, a striking pattern emerged: the time-unit boundaries are not evenly spaced.

Instead, the boundaries appear in clusters, separated by long intervals of relative quiet. This extreme unevenness was described using the concept of multifractals鈥攎athematical patterns that repeat at different scales.

"The intervals between key events in Earth's history, from mass extinctions to evolutionary explosions, are not scattered completely evenly. They follow a multifractal logic that reveals how variability cascades through time," explains Prof. Spiridonov.

How much time does it take to reveal Earth's true face?

This analysis allowed the researchers to estimate the "outer time scale" of Earth's system鈥攖he time span needed to reveal the full extent of its natural variability. That limit, they found, is approximately 500 million years or even longer.

"If we want to understand the full range of Earth's behaviors, whether periods of calm or sudden global upheaval, we need geological records that cover at least half a billion years. And ideally, a billion," notes Prof. Spiridonov.

According to the authors of the study, this insight helps explain why shorter timescales often fail to capture the extremes鈥攂oth stable and chaotic鈥攖hat define planetary evolution.

Events within events: hidden patterns behind the chaos

The study also introduces a new theoretical model to describe how these geological boundaries are distributed: the Compound Multifractal-Poisson Process. This model suggests geological events are nested within one another, forming a cascading pattern where clusters appear within clusters, all governed by a single statistical process.

"We now have mathematical evidence that Earth system changes are not just irregular. They are deeply structured and hierarchical. This has huge implications not only for understanding Earth's past but also for how we model future planetary change," concludes Prof. Spiridonov.