The world's oldest secrets revealed by 450-million-year-old diamonds

It turns out that diamonds are not just a material used by humans for adornment, but can also be quite useful for geologists. In fact, as a new study reveals, some diamonds can even uncover secrets about the evolution of the Earth.

Diamonds, the hardest natural mineral known, have survived and persisted through many events, including the creation and destruction of "supercontinents." According to the study reported by Chip, researchers analyzed diamonds that formed millions of years ago beneath the supercontinent Gondwana, which was buried deep beneath the Earth's surface.

These "super-deep" gems hold important clues about the formation, stabilization, and movement of the supercontinent on the planet, known as the "supercontinent cycle." Studying this cycle, which is driven by plate tectonics that push the crust beneath the Earth's surface, can normally be difficult.

Oceanic crust is very young, and old continental crust does not provide much insight into deep geological processes.

Study author Karen Smit stated, "Super-deep diamonds are extremely rare, and we now know that they can tell us a lot about the entire process of continental formation," adding: "We wanted to determine the history of these diamonds to understand how the oldest continents were formed."

Using a series of chemical analyses, including isotopic analysis, to identify and date small silicate and sulfide inclusions in the diamonds, the researchers found that they formed 650 to 450 million years ago, approximately 300 to 700 kilometers below the base of Gondwana. At that time, this supercontinent covered the South Pole.

SHEDDING LIGHT ON MILLIONS OF YEARS AGO

As they formed, the rocks they were in became buoyant and were transported to the base of the supercontinent along with mantle material from below, expanding it from underneath. And as Smit explained, the diamonds have had quite a long journey since then: "About 120 million years ago, Gondwana began to break apart to form today's oceans, such as the Atlantic. 90 million years ago, the diamonds, carrying small trapped remnants of the host rock, were brought to the Earth's surface by violent volcanic eruptions."

These eruptions occurred in the parts of Gondwana that we now know as Brazil and West Africa. The researchers suggest this indicates that the diamonds were "stuck" to the base and thus migrated with different parts of the supercontinent as it separated.

This study highlights the importance of research into clues about continental formation beneath the sparkling exterior of super-deep diamonds. As Smit noted, "We need this kind of research to understand how continents evolve and move. Without continents, there would be no life. This research provides us with insights into how continents formed and connects to how life evolved and what makes our planet Earth different from other planets."

The study was published in the journal Nature.

News Source: 12punto

Related News

Norwegian scientists reveal three factors that determine individual happiness

Scientists propose laser solution for road problem on the Moon

Temperatures in September surprised scientists: 'An extraordinary record'