Scientists are developing a new method for studying early life in old stones

Scientists have developed a new method to detect traces of primordial life in ancient rock formations using potassium.

The method relies on searching for high concentrations of potassium in old sedimentary rocks instead of traditional methods that look for carbon, sulfur or nitrogen, which can occur in old rocks through processes that are not related to the old life. .

"Our results show that microbial biofilms captured potassium from old seawater and facilitate its accumulation in clay minerals buried on the seabed," explained University of Alberta microbiologist and geochemist Kurt Konhauser, co-author of the study.

"This is critical because there is no abiotic mechanism that can be used to explain the potassium enrichment except for life itself."

The study examined clay particles from Francevillian formation in Gabon, on the west coast's central coastal Africa. The 2.1 billion-year formation hosts well-preserved microfossils in clay.

"In our quest to find evidence of the early life on Earth, we have been limited to looking for a number of signatures, all of which have proved to be ambiguous because, unfortunately, the signatures can be explained by both bacterial and abiotic processes. "Konhauser explained.

"Our results show that another signature potassium may be a more unique tram, as it could only have been created through the metabolism of living bacteria."

The research was led by Jérémie Aubineau and Abder El Albani from Poitiers University in France.

The study "Microbially Induced Potassium Enrichment in Paleoproterozoic Shales and Implications for Reverse Weathering on Early Earth" was published in Nature Communications .