Mineralogists from St Petersburg University find a possible source of prebiotic phosphorus on Disko Island

According to Oleg Vereshchagin, the corresponding author of the article, Associate Professor in the Department of Mineralogy at St Petersburg University, while studying the volcanic rocks of Disko Island, the scientists discovered phosphide-bearing mineral assemblages with native iron. Some of these minerals contain phosphorus in the negative form of oxidation. These compounds could be the sources of phosphorus necessary for the first living organisms (prebiotic phosphorus).

The findings of the research supported by a grant from the Russian Science Foundation are published in the scientific journal Geoscience Frontiers.

To date, the prevailing opinion in the scientific literature is that the source of prebiotic phosphorus was meteorites, since minerals containing phosphorus in the negative form of oxidation are practically not found on Earth. Joint research by the scientists from St Petersburg University and the Udmurt Federal Research Centre allowed a new look at this problem and showed that assemblages of such minerals of significant volume can be formed in terrestrial conditions.

Oxygen is one of the basic elements of the Earth’s crust. Almost all iron in the Earth’s crust is therefore found in the form of oxides (hematite and magnetite). The occurrence of native iron requires almost complete absence of oxygen in the mineral forming system, which is rarely achieved under terrestrial conditions. At the same time, the geochemical cycles of iron and phosphorus are closely linked. It is the highly reducing conditions and the abundance of iron that led to the formation of a significant number of minerals containing phosphorus in the negative form of oxidation.

Oleg Vereshchagin, the corresponding author of the article, Associate Professor in the Department of Mineralogy at St Petersburg University

Oleg Vereshchagin added that in studying the Disko Island volcanites, the scientists from St Petersburg University had access to a range of local instrumental techniques that had not previously been used on such objects. This made it possible to identify a number of rare and unusual minerals, establish patterns of their formation, and make assumptions about how the first organic molecules appeared. 

"In particular, we identified a number of minerals characteristic of meteorites, such as nickelphosphide, schreibersite, taenite, and anhydrous Fe-Na phosphates. Finally, we paid attention to phosphorus impurity in native iron and assumed that not only phosphides, but also iron could be a source of prebiotic phosphorus," said Oleg Vereshchagin.

Phosphorus is one of the key elements necessary for the origin and maintenance of life. One of the main concepts suggests that the source of soluble reactive phosphorus could be phosphides that contain it in the negative form of oxidation and are easily oxidised to chemically active phosphorus compounds.

Oleg Vereshchagin, Associate Professor in the Department of Mineralogy at St Petersburg University

"Nevertheless, phosphides are virtually unknown on present-day Earth because they form under highly reducing conditions. Native iron, which is the dominant component in the phosphide mineral association, could also be a source of phosphorus, as it is easily oxidised and may contain a sufficient amount of phosphorus," explained Oleg Vereshchagin, Associate Professor at St Petersburg University. 

The research of the scientists from St Petersburg University shows that native-iron bearing rocks could have been formed under the conditions of the early Earth, when near-surface basalts came into contact with a strong reducing agent (hydrocarbons, methane or hydrogen). 

In future, the scientists from St Petersburg University plan to study other native-iron bearing objects, paying particular attention to rare and unusual minerals. For example, the next plan is to study the famous native-iron bearing deposits of Siberia. 

The research is supported by the grant from the Russian Science Foundation (project No 23-77-10025). The study was carried out using the facilities of the St Petersburg University Research Park: the Resource Centre for Optical and Laser Materials Research; the Resource Centre for Microscopy and Microanalysis; the Resource Centre for Geo-Environmental Research and Modelling (GEOMODEL); and the Resource Centre for Nanofabrication of Photoactive Materials (Nanophotonics Centre).

St Petersburg University, the oldest university in Russia, was founded on 28 January (8 February) 1724. This is the day when Peter the Great issued a decree establishing the University and the Russian Academy of Sciences. Today, St Petersburg University is an internationally recognised centre for education, research and culture. In 2024, St Petersburg University celebrates its 300th anniversary. 

The plan of events during the celebration of the anniversary of the University was approved at the meeting of the Organising Committee for the celebration of St Petersburg University’s 300th anniversary. The meeting was chaired by Dmitry Chernyshenko, Deputy Prime Minister of the Russian Federation. Among the events are: the naming of a minor planet in honour of St Petersburg University; the issuance of bank cards with a special design; and the branding of the aircraft of the Rossiya Airlines to name just a few. To mark the 300th anniversary of St Petersburg University, a postage stamp depicting the Twelve Collegia building and the monument to Count Sergey Uvarov was issued. 

By the decision of the Governor of St Petersburg Alexander Beglov, 2024 is a year of the 300th anniversary of St Petersburg University in St Petersburg. On the day of the University’s 300th anniversary torches were lit on the Rostral Columns on the Spit of Vasilyevsky Island. St Petersburg University flags were raised on the Palace Bridge. The city public transport was decorated with the University’s symbols. New tourist maps will feature the locations of the University buildings, with thematic and historical materials about the University placed nearby. During St Petersburg’s City Day celebrations in May 2024, St Petersburg University will be a participating venue. The traditional ‘Scarlet Sails Festival’ will also be dedicated to the anniversaries of St Petersburg University and the Russian Academy of Sciences. Additionally, the University has launched a website dedicated to the upcoming holiday. The website contains information about outstanding University staff, students, and alumni; scientific achievements; and details of events held as part of the celebration of the 300th anniversary of the University.