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Evidence for Microfossils in Ancient Rocks and MeteoritesThe McKay et all. detection of chemical biomarkers and possible microfossils in an ancient meteorite from Mars (ALH84001) stimulated research in several areas of importance to the newly emerging field of Astrobiology. Their report resulted in a search for additional evidence of microfossils in ancient terrestrial rocks and meteorites. These studies of ancient rocks and meteorites were conducted independently (and later collaboratively) in the United States and Russia using the SEM, Environmental Scanning Electron Microscope (ESEM), and Field Emission Scanning Electron Microscope (FESEM). We have encountered in-situ in freshly broken carbonaceous chondrites a large number of complex microstructures that appear to be lithified microbial forms. The meteoritic microstructures have characteristics similar to the lithified remains of filamentous cyanobacteria and bacterial microfossils we have found in ancient phosphorites, ancient graphites and oil shales. Energy Dispersive Spectroscopy (EDS) and Link microprobe analysis shows the possible microfossils have a distribution of chemical elements characteristic of the meteorite rock matrix, although many exhibit a superimposed carbon enhancement. We have concluded that the mineralized bodies encountered embedded in the rock matrix of freshly fractured meteoritic surfaces can not be dismissed as recent surface contaminants. Many of the forms found in-situ in the Murchison, Efremovka, and Orgueil carbonaceous meteorites are strikingly similar to microfossils of coccoid bacteria, cyanobacteria and fungi such as we have found in the Cambrian phosphorites of Khubsugul, Mongolia and high carbon Phanerozoic and Precambrian rocks of the Siberian and Russian Platforms.
Document ID
19990098008
Acquisition Source
Marshall Space Flight Center
Document Type
Preprint (Draft being sent to journal)
Authors
Hoover, Richard B.
(NASA Marshall Space Flight Center Huntsville, AL United States)
Rozanov, A. Y.
(Academy of Sciences (USSR) Moscow, USSR)
Zhmur, S. I.
(Academy of Sciences (USSR) Moscow, USSR)
Gorlenko, V. M.
(Academy of Sciences (USSR) Moscow, USSR)
Date Acquired
August 19, 2013
Publication Date
January 1, 1998
Subject Category
Astrophysics
Meeting Information
Meeting: System
Location: Greenbelt, MD
Country: United States
Start Date: October 2, 1998
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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