Back تكوين الحديد الحزامي Arabic Formació de ferro bandat Catalan Páskovaná železná ruda Czech Båndet jernformation Danish Bändereisenerz German Banded iron formation English Formación de hierro bandeado Spanish Rautamuodostuma Finnish Formation ferrifère rubanée French Formasi besi berpita ID
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Banded iron formations (or BIFs) are a distinctive type of rock often found in Precambrian sedimentary rocks.
They consist of repeated thin layers of iron oxides, either magnetite (Fe3O4) or hematite (Fe2O3), alternating with bands of iron-poor shale and chert.
Some of the oldest known rock formations, formed over 3,700 million years ago (mya), include banded iron layers.[1] The banded layers are a common feature in sediments for much of the Earth's early history.[2][3]
- ↑ Minik T. Rosing et al. 1996. Earliest part of Earth's stratigraphic record: A reappraisal of the >3.7 Ga Isua (Greenland) supracrustal sequence. Geology 24 #1, 43-46
- ↑ Knoll, Andrew H. 2004. Life on a young planet: the first three billion years of evolution on Earth. Princeton, N.J. ISBN 0-691-12029-3
- ↑ Faces of Earth - Building the Planet. YouTube account of early Earth history. [1] American Geosciences Institute.