ABOVE: One of the samples used in the study, showing crystals of calcite covered in small grains of pyrite
HENRIK DRAKE
The Earth’s crust, or at least the part of it under Scandinavia, is packed with clues of ancient microbial life, according to a study published today (June 3) in Communications Earth & Environment. Researchers analyzed mineral samples from more than 30 underground sites in Sweden and nearby countries and identified molecular and isotopic signatures of microbial activity stretching back at least 50 million years, adding further support to the idea that life has long survived deep beneath the surface of the Earth.
The paper “builds on quite a number of previous articles that describe various forms of evidence for ancient life in the subsurface,” particularly in this area of the world, says Sean McMahon, an astrobiologist at the University of Edinburgh who was not involved in the project but says ...
