Jarosite formation by an AMD sulphide-oxidizing environmental enrichment: Implications for biomarkers on Mars

The formation of jarosite in acid mine drainage (AMD) accompanies microbial oxidation of reduced sulphidic minerals such as pyrite (FeS2) and pyrrhotite (Fe1−xS) found in mining waste materials. The discovery of jarosite at Meridiani Planum, Mars has been used to interpret past hydrologic conditions as episodically wet, acidic and evaporative based on evidence from jarosite formed abiotically or through microbial iron oxidation. To date, no …