Furthermore, there is a banded iron formation present in the bluffs.

Huge deposits have been found in banded iron formations.

Here, up to 300 million years is represented by a single unit of banded iron formation and shale.

This 'mass rusting' led to the deposition of banded iron formations.

Greenalite occurs as a primary phase in banded iron formations.

Banded iron formations are known as taconite within North America.

Nearly pure hematite is present in some metamorphosed banded iron formations.

Contemporary local bacteria ended up forming banded iron formations and stromatolites.

The Precambrian deposits, which have a different origin, are generally known as banded iron formations.

Jaspilite is a banded iron formation rock that often has distinctive bands of jasper.

Banded iron formations form during this period.

Magnetite also occurs in many sedimentary rocks, including banded iron formations.

It is a large iron ore belt developed on banded iron formations and has had mining operations since 1954.

It occurs in banded iron formations as the asbestiform variety crocidolite (blue asbestos).

Banded Iron Formation - distinctive type of rock often found in primordial sedimentary rocks.

Stilpnomelane occurs associated with banded iron formations.

Abundance of banded iron formations (BIFs) peaked early this period.

For the first billion years, any free oxygen produced by these organisms combined with dissolved iron in the oceans to form banded iron formations.

Ancient microfossils have been found in the banded iron formations of the Gunflint Chert.

Banded iron formations occur exclusively in Precambrian rocks, and are commonly weakly to intensely metamorphosed.

The red pebbles or cobbles in the conglomerate are fragments of jasper or banded iron formation.

Ankerite occurs with siderite in metamorphosed ironstones and sedimentary banded iron formations.

Evidence for this lies in older rocks that contain massive banded iron formations, laid down as iron and oxygen first combined.

They often contain a mixture of banded iron formations and granular iron formations.

Oxygen causes deposit of iron as iron oxides in banded iron formations.