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Possible Microfossils (Warrawoona Group, Towers Formation, Australia, approximately 3.3 - 3.5 Ga)Early in the twentieth century there were reports of Archean stromatolite-like structures that were similar to organic rich stromatolites from the base of the Cambrian (600 m.y.). It was not until the latter half of this century that fossilized Archean-age (3.9-2.5 Ga) life forms were found in the Fig Tree Formation of South Africa and the Towers Formation of Australia. Some of the ancient stromatolites contained streaks and clots of kerogen, pyrite grains, remnants of microbial cells, and filaments that represented various stages of preservation, while others appeared to lack fossils. A set of physical criteria was established for evaluating the biogenicity of these Archean discoveries: (1) rocks of unquestionable Archean age; (2) microfossils indigenous to Archean sediments; and (3) microfossils occurring in clasts that are syngenetic with deposition of the sedimentary unit. In the case of bedded cherts, the fossils should predate the cherts; (4) the microfossils are biogenic; and (5) replicate sampling of the fossil-iferous outcrop firmly demonstrates the provenance of these microfossils. Sample 002 from the Precambrian Paleobiology Research Group (PPRG) was examined. This stromatolitic carbonaceous chert contains microbial remains that meet the established criteria [10]. Using a scanning electron microscope (SEM), we have analyzed the morphologies and chemistry of these possible microbial remains.
Document ID
Acquisition Source
Johnson Space Center
Document Type
Morris, P. A.
(Houston Univ. TX United States)
Wentworth, S. J.
(Lockheed Martin Corp. Houston, TX United States)
Allen, C. C.
(Lockheed Martin Corp. Houston, TX United States)
McKay, D. S.
(NASA Johnson Space Center Houston, TX United States)
Date Acquired
August 19, 2013
Publication Date
January 1, 1998
Publication Information
Publication: Workshop on the Issue Martian Meteorites: Where do we Stand and Where are we Going?
Subject Category
Life Sciences (General)
Funding Number(s)
Distribution Limits
Work of the US Gov. Public Use Permitted.

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