Encyclopedia of Astrobiology

2011 Edition
| Editors: Muriel Gargaud, Ricardo Amils, José Cernicharo Quintanilla, Henderson James (Jim) CleavesII, William M. Irvine, Daniele L. Pinti, Michel Viso

Apex Chert, Microfossils

  • Daniele L. Pinti
  • Wladyslaw AltermannEmail author
Reference work entry
DOI: https://doi.org/10.1007/978-3-642-11274-4_1866


 Apex chert,  apex basalt, biomarkers, cyanobacteria,  microfossils


The Apex Chert is a bedded, microcrystalline silica (SiO2) deposit interlayered with pillow lavas and massive flows of the Apex Basalt Formation,  Pilbara Craton, Western Australia. The basalts were dated at 3,465–3,458 Ma. The origin of the chert is disputed and interpretations of primary silica deposition on the ocean floor or alternatively secondary, hydrothermal silicification (chertification) of clastic or carbonate sedimentary and volcano-sedimentary rocks rival one another. The putative microfossils of Apex Chert are carbonaceous filaments found in ca. 3,465 Ma old chert lenses at the so-called “Schopf locality,” Chinaman Creek near Marble Bar.


The name of the locality derives from that of the American paleontologist and paleobiologist, J. William (Bill) Schopf, who, at this site, reported 11 morphological taxa of prokaryotic, filamentous, and coccoidal microfossils embedded in chert...
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References and Further Reading

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© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  1. 1.GEOTOP & Department of Earth and Atmospheric sciencesUniversité du Québec à MontréalMontréalCanada
  2. 2.Department of GeologyUniversity of PretoriaPretoriaSouth Africa