Earth's 2 Billion Year-Old Carbon Isotope Anomaly May Be a Local Event

A new study led by the California Institute of Technology has revealed that an important 2-billion-year-old chemical trace of the oxygenation process that paved the way for life on Earth may have resulted from local geological events rather than a global carbon crisis as thought.

In the international study, researchers analyzed rock samples extracted from the Zaonega Formation in the Karelia region of Russia, which is considered one of the oldest fossil oil fields in the world. Scientists examining gases trapped in the microscopic pores of rocks examined carbon isotope anomalies, which are shown in the literature as evidence of a massive planet-wide environmental transformation.

It was determined that the signal, which has been called the 'Shunga-Francevillian event' for many years and is thought to indicate that the Earth's carbon balance has deteriorated on a global scale, occurred in a limited marine sedimentary basin of several hundred square kilometers.

According to analysis; The incandescent magma seeping into the organic matter-laden sedimentary layer on the sea floor heated the area, causing the release of hydrocarbons such as methane and propane. As a result of the consumption of these gases rising towards the sea floor by methane-feeding microorganisms, biomass bearing traces of light carbon isotopes was formed and remained locked in rocks until today.

The lead author of the study, Dr. Nivedita Thiagarajan stated that chemical processes identical to those seen in modern oil and gas basins were detected in 2 billion-year-old sediments, and emphasized that the reference region in question does not represent a global disaster.

In the next stage, the international scientific delegation will examine the drilling cores extracted from the 'Francevillian Basin' in the African country of Gabon, where a similar isotopic structure is found; It has been reported that if the same local mechanism applies there, the evolution models of the early Earth will be rewritten.