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.Organismic and Evolutionary Biolog

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.Organismic and Evolutionary Biolog

Letter to H.B. Stenzel from Elso S. Barghoorn on 1950-06-07

Jackson School of Geoscience

Letter to Henryk B. Stenzel from Elso S. Barghoorn on 1950-05-10

Jackson School of Geoscience

DEGRADATION OF PLANT REMAINS IN ORGANIC SEDIMENTS

Volume: 14Start Page: 1End Page: 2

Travel and field notebooks,

Journal 9 (1967

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 (5-15 mu m) coccoid taxon morphologically comparable to Huroniospora Barghoorn, a larger coccoid form comparable to an apparently planktonic alga from the Gunflint, Gunftintia Barghoorn, 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.Organismic and Evolutionary Biolog

Travel and field notebooks,

Journal 17 (1973

Travel and field notebooks,

Journal 7 (1965-1966