secondary minerals along the river, but it has also posed new ones, such as the paradox of the unexpectedly high level of diverse complex eukaryotic microorganisms or the need to explain the detection of functional activities in non-permissive environmental conditions, all of which are of astrobiological interest. The discovery of Noachian iron lithological units on Mars, similar to those produced biologically in the Tinto basin, have given Rio Tinto the status of geochemical and mineralogical terrestrial analogue that can lead to a more detailed vision of the possible geomicrobiological processes that may have driven the generation of iron oxides and sulfates on Mars.
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