Sentence examples for iron formation from inspiring English sources

The origin of banded iron formation is not clearly understood.

"Most of it was laid down about three billion years ago, when this iron formation was sea bottom.

Banded iron formation units are typically 50 to 600 metres thick.

Two major types of iron-rich sedimentary rocks are recognized: (1) iron formation, or banded iron formation (BIF regionally extensive, locally thick sequences composed of alternating thin (millimetre to centimetre thick) layers of mainly crystalline-textured iron-rich minerals and chert and (2) ironstone noncherty, essentially clastic-textured, iron-rich minerals of local extent.

Many sedimentary petrologists consequently conclude that banded iron formation deposition is a uniquely Precambrian occurrence made possible by, and supporting the existence of, an earlier anaerobic Earth atmosphere (one lacking free oxygen) quite unlike that in existence today.

Sequence 1 reflects deposition of hematitic peritidal iron formation as deep as the upper shoreface.

In other words, much of the iron in iron formations may come pre-owned.

The study examines the iron formations of the Hamersley Basin, in western Australia.

The iron formations precipitated from seawater, but where did the dissolved iron come from in the first place?

The ancient iron formations share many characteristics with modern limestones, which suggests that they accumulated in a marine environment.

The most important iron-bearing minerals in iron formations are hematite, magnetite, and greenalite.