Isotope and microelement systematics of Gallionella sp.-containing bacterial mats from the northwest of the East European Platform.

Microelement composition of Gallionella sp.-containing bacterial mats from the environs of St. Petersburg and isotope composition of organic carbon, strontium, and neodymium from these mats have been determined. Isotope and microelement systematics of iron oxides of bacterial origin characterize the geochemistry of aquafacies that contain ferrobacteria. Certain pre-Cambrian ferruginous quartzites have a similar composition; therefore, one may assume that bacterial oxidation of iron under continental conditions had occurred upon the formation of ironstone during the Precambrian.

Cyanobacteria(?) in iron banded formations of the Kursk magnetic anomaly.

Fossilized cyanobacteria(?) represented by trichomes enclosed in common sheaths were detected in early Proterozoic iron banded formations of the Kursk magnetic anomaly (limonite-martite ores of the Lebedinsky mine and iron banded formations of the Korobkovskoye deposit). These fossils morphologically similar to current representatives of the genus Microcoleus were buried in situ.