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Stromatolites are the earliest geological evidence of the existence of life on Earth. It is believed that they appeared on the planet 3,48 billion years ago and for a long time were the only sources of carbonates in ecosystems. They also contributed to the saturation of the atmosphere with oxygen. science
As more and more organisms adapted to the oxygen atmosphere, the number of stromatolites began to decrease. They appeared in the geological annals only after mass extinctions or in difficult conditions.
Until recently, the only known modern analogue of marine ecosystems where Proterozoic stromatolites developed were the Exuma Islands in the Bahamas. But recently, scientists discovered new specimens on the island of Shaybara (north-eastern shelf of the Red Sea in Saudi Arabia).
Scientists were studying the structure of domes made of salt crust when they came across a deposit of stromatolites. Sheybara Island is located in the intertidal zone, where periods of wetting and drying regularly alternate, as well as extreme temperature changes from 8 to more than 48 degrees Celsius.
Scientists noted that the diameter of stromatolites is about 15 cm, so they are difficult to detect. They managed to identify several hundred similar formations.
It turned out to be almost impossible to date stromatolites, since they contain two different carbonate components. However, the discovery will make it possible to better understand the formation and growth of stromatolites. This will give scientists insight into early life and the evolution of Earth's oceans and may even help in the search for life on other planets, Geology reports.
