Very old stromatolites – evidence of very old life and waters at 3.7 billion years, LA-ICP-MS – SIMS

At Greenland, Earth’s oldest stromatolites were found (Nutman, 2016, Nature 537). Data from the U and Pb (geochronology) isotopes obtained by mass spectrometry indicated that the formation of these stromatolites occurred at 3.7 billion years ago and additional chemical analyzes show signatures consistent with a biological origin (microorganism). There is some controversy in the scientific community about the existence of these archean (>2.5 Ga) microorganisms, since few stromatolites contain fossilized microorganisms but information about the presence of water and the technique of dating by U-Pb geochronological method by means of mass spectrometry are extremely safe. (Keynote speaker: Allen P. Nutman).