Unraveling the three-dimensional morphology of Archean microbialites

摘要: Fenestrate microbialites from the 2521±3 Ma Gamohaan Formation, South Africa, are composed of calcite with traces kerogen that represent remains ancient microbial mats. To delineate 3-D geometry these microbialites, specimens were serial-sectioned; sequential slices polished in 120 μm increments and scanned to yield an image stack, which was rendered into a virtual model microbialites. The resulting representation allowed for visualization characterization growth geometries not visible 2-D surfaces. Several new insights structure emerged characterizing their including recognition two features, linear structures tubular structures. long, thin nature makes them difficult identify dimensions. However, three dimensions, they can be traced as ropes fossilized communities emerging more typical mat Overall, results demonstrate set features Formation only characterized by reconstructing full