The present report describes the stereochemistry of amino acids under extreme conditions of 156degreesC and greater than 140 atmospheres in a submarine volcanic hydrothermal subvent. The lack of evidence of abiotically synthesized amino acids such as omega-amino acid specimens and unexpected large enantiomeric excesses Of L-form amino acids support the existence of a vigorous subjacent microbial oasis, which extends the known terrestrial habitable zone.