The truth from the 4.2 billion year old "treasure"

(NLDO) - Zircon crystals remaining from the Hadean eon have revealed the time when an event essential for life on Earth began.

In a study recently published in the journal PNAS , scientists studied nearly 1,000 zircons collected from the Jack Hills region of Australia, which holds important geological evidence of the Earth's "infancy."

The results showed that more than 35% of these zircons belonged to the S type, a crystal group that represents plate tectonic activity.

The "hot" Earth entered the Hadean eon - Photo AI: Anh Thu

Plate tectonics is the process by which tectonic plates - which can be roughly understood as pieces of the Earth's crust - shift, slide over each other, emerge from the mantle, or sink.

Although it causes catastrophic events - from continents merging and breaking apart to earthquakes and volcanoes - plate tectonics also plays an important role in stabilizing the climate and atmosphere, and maintaining the chemical balance of the planet.

Therefore, plate tectonics is one of the necessary conditions for the Earth to generate and preserve life.

Previously, it was thought that this process only began after or at the end of the Hadean eon, the "fireball" period of Earth, which lasted from Earth's conception until 3.8 billion years ago.

However, among the newly identified S-type zircons in Australia, there is a date of 4.2 billion years ago.

It is evidence of the beginning of tectonic activity.

During the Hadean eon, Earth possessed a watery atmosphere of ammonia and methane, which eventually condensed into a planet-covering ocean. During this period, Earth gradually cooled to form a solid outer shell.

The 4.2-billion-year-old zircon "treasures" show that at that time, the outer crust had not only formed but had also split into tectonic plates, initiating a shift that was crucial to the planet's evolution.

This shows that our planet went through a much more turbulent and rapidly evolving early period than previously thought.

The work was led by a team of authors from the Institute of Geology and Geophysics and the University of Earth and Planetary Sciences, both of the Chinese Academy of Sciences.

Source: https://nld.com.vn/su-that-tu-bau-vat-42-ti-nam-196240717114006392.htm