Morphology as an indictor of biogenicity for 3.5-3.2 Ga Fossil stromatolites from the Pilbara Craton, Western Australia

Abstract

Stromatolites were recognised in 3.5-3.4Ga rocks from the Pilbara Craton 30 years ago (Walter et al. 1980; Lowe 1980), but their biogenicity has been cast in doubt by recent studies of abiogenic features with gross similarity to biogenic forms (Grotzinger and Rothman 1996; Garcia-Ruiz et al. 2003) and new interpretations of geological settings that differ from original models (see below). This paper reviews the geological setting of Pilbara fossils and assesses stromatolite biogenicity, showing the critical value of stromatolite morphology when used in combination with well documented geological context. © 2011 Springer Berlin Heidelberg.