Precambrian Banded Iron Formation.

Using modern ferruginous habitats to interpret Precambrian banded iron formation deposition

Early Earth processes are typically identified through the study of mineralogical, elemental and isotopic features in the rock record, including Precambrian banded iron formations (BIF). However, postdepositional processes often obscure the primary geochemical signals, making the use of BIF as proxies for paleo-seawater and the paleo-biosphere potentially imprecise. Thus, alternative approaches...

Iron isotopes constrain biologic and abiologic processes in banded iron formation genesis

The voluminous 2.5 Ga banded iron formations (BIFs) from the Hamersley Basin (Australia) and Transvaal Craton (South Africa) record an extensive period of Fe redox cycling. The major Fe-bearing minerals in the Hamersley–Transvaal BIFs, magnetite and siderite, did not form in Fe isotope equilibrium, but instead reflect distinct formation pathways. The near-zero average dFe values for magnetite r...

Fossilized iron bacteria reveal pathway to biological 2 origin of banded iron formation 3

banded iron - formations , Weld Range , Western Australia

There are two basic Fe-rich lithologies at Weld Range: (l) banded iron-formation containing minnesotaite, siderite, quarlz,magnetite, greenalite, stilpnomelane, pyrite, and chamosite with trace amounts of pyrrhotite, arsenopyrite, chalcopyrite, apatite, and rockbridgeite; Q) Fe-shale. which occurs as laminated 2-30cm-thick bands within banded iron-formation, containing chamosite, stilpnomelane,...

Sedimentary mechanisms of a modern banded iron formation on 2 Milos Island , Greece