KEY POINTS

  • A new study revealed that Earth's molten core is leaking
  • Iron isotopes are migrating to Earth's mantle
  • Scientists believe the core has been leaking for billions of years

A new study has revealed that the molten core of Earth might be leaking iron. According to the authors of the study, it is possible that the core has been leaking iron for billions of years now.

The new study was conducted by a team of scientists led by geology professor Charles Lesher of the University of California Davis. Their findings were presented in a new study published in the journal Nature Geosciences.

According to the scientists, a boundary exists between Earth’s rocky mantle and its molten core. Located at about 2,900 kilometers below the Earth’s surface, the temperature at this boundary drops by over a thousand degrees.

As noted by the scientists, the sudden drop in temperature at the boundary is causing heavy iron isotopes to leak out from the molten core. This occurs as the iron isotopes migrate toward cooler temperatures of the rocky mantle.

The scientists believe this could be the reason why the lowest levels of Earth’s mantle contain heavy iron isotopes.

“The D layer at the base of the Earth’s mantle exhibits anomalous seismic properties, which are attributed to heat loss from and chemical interaction with the underlying molten Fe-rich outer core,” the scientists wrote in the abstract of their study.

“Here we show that mass transfer due to temperature variations within the D” layer could lead to resolvable fractionation of iron isotopes,” they continued.

As noted by Lesher, their study could explain the anomaly commonly found in lava emissions and eruptions. While studying underground emissions, scientists often discover that they contain more heavy isotopes than chondrite meteorites, which are the ancient materials that came from the formative years of the Solar System.

According to Lesher and his colleagues, the presence of heavy iron isotopes in materials from the Earth’s mantle is a clear indication that the molten core is leaking. Since traces of heavy iron isotopes often outnumber chondrite meteorites in mantle rocks, the scientists believe this material has been leaking from the core for a long time.

“If true, the results suggest iron from the core has been leaking into the mantle for billions of years,” Lesher stated.

A portion of cliff collapses cutting off the ongoing flow of lava that had been spilling out of Kamokuna cliff since New Year's Eve. Lava free-falls into the sea from Kilauea Volcano in Hawaii on July 26,2002. Photo: REUTERS/Courtesy US Geological Survey Hawaiian Volcano Observatory