Figure 3: Whole rock chemistry.
From: Fossilized iron bacteria reveal a pathway to the biological origin of banded iron formation
(a) Behaviour of silica, haematite, Al2O3 and TiO2. (b) NASC normalized REE fractionation profiles. Minimum detection limit (MDL) varied from 0.01 to 0.1 p.p.m. (c) Behaviour of major elements. MDL ranged from 0.002 for Cr2O3 to 0.04 wt% for Fe2O3. Cr2O3 was consistently below the detection limit. (d) Trace elemental composition. MDL varied from 0.1 to 1 p.p.m., with the exception of Ni that had an MDL of 20 p.p.m. and was below the MDL. Bi, Sn and Se were below MDL (0.1, 1, 0.5, respectively). Unusually high As and Pb concentrations (>8,000 and 10,000 p.p.m., respectively) were identified in the jaspers in banded 4, respectively.
