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Biomedical subjects

E S Barghoorn

Publications and source records attributed to E S Barghoorn.

9 recordsLinked to original sources
PubMed1979

The Viking Mission: implications for life on Mars.

The results of the Viking Biology experiments are best explained by non-biological phenomena: The interaction of the reagents with the materials comprising the regolith. Conditions of water activity, temperature, availability of carbon sources and others in most regions of the planet are too extreme for survival and growth of any known Earth microorganisms. Although the possibility persists that some very unusual form of life is somewhere on that planet the evidence is best interpreted as negative. Even though there is no evidence for current life on Mars, whether or not life ever originated there is not known.

Carbon↗
PubMed1976

A gunflint-type microbiota from the Duck Creek dolomite, western Australia.

Two billion year old black chert lenses from the Duck Creek formation, northwestern Western Australia, contain abundant organically preserved microorganisms which are morphologically similar to fossils of approximately the same age from the Gunflint formation, Ontario. Entities include: a relatively small (5-15mum) coccoid taxon morphologically comparable to Huroniospora Barghoorn, a larger coccoid form comparable to an apparently planktonic alga from the Gunflint, Gunflintia Baghoorn, and Eoastrion Barghoorn (Metallogenium Perfil'ev). Gunflint-type assemblages had a wide geographic distribution in middle Precambrian times, and these assemblages may eventually prove useful as biostratigraphic indices.

Australia↗
PubMed1975

Paleopleurocapsa wopfnerii gen. et sp. nov.: A Late Precambrian alga and its modern counterpart.

Silicified dolomite of the approximately one billion year old Skillogalee Dolomite of the Adelaide Geosyncline, South Australia, contains organically preserved microfossils of a structurally complex, crustose pleurocapsalean cyanophyte, herein described as Paleopleurocapsa wopfnerii. Although actual cell contents have been degraded, lamellar sheath material faithfully preserves the morphology of the alga. Comparison with specimens of the modern genus Pleurocapsa Thuret demonstrates affinities at the family level and quite possibly even generic identity.

Journal Article↗
PubMed1974

Ambient pyrite in precambrian chert: new evidence and a theory.

Ambient pyrites of two distinct types were described from middle Precambrian rocks of the Lake Superior area. A new class of this phenomenon is here described from middle Precambrian chert from western Australia. The newly found ambient pyrites are quite minute and characteristically occur in groups forming a "starburst" pattern. All three types of ambient pyrite may be explained in terms of pressure solution initiated by gas evolution from organic material attached to the pyrite. Thermal degradation of the kerogen produces the gases which, due to the impermeability of the encompassing chert, build up the pressures necessary to initiate solution. Pyrite appendages bear a striking resemblance to micro-organisms and, thus, constitute the smallest pseudofossils known.

Journal Article↗
PubMed1970

Micropaleontological study of lunar material.

Samples of the lunar dust, rock chips, and thin sections of rocks from Tranquillity Base have been examined by use of white light and electron optics. In transmitted and in dark-and bright-field incident light and in the scanning electron beam the material reveals no indication of biological morphology. It is inferred that the lunar regolith has always been devoid of life. section preparations.

Astronomical Phenomena↗
PubMed1965

Electron microscopy of fossil bacteria two billion years old.

Occurrence of well-preserved rod-shaped and coccoid bacteria in the Precambrian Gunflint chert (1.9 x 10(9) years old) has been demonstrated by electron microscopy. This appears to be the oldest definite occurrence of bacteria in the fossil record. The organisms are morphologically comparable with certain modern iron bacteria.

Bacteria↗