Online Store > Other MysteriesView Cart - My Account

176-Banded Iron Formation, Precambrian Age $10.00
Mystery includes rock, fossil, or mineral sample and Mystery questions with teaching instructions.

A piece of Banded Iron Formation from the Upper Peninsula of Michigan

To introduce Banded Iron Formation and the iron mining industry in Michigan
To study very old rocks and continents from the Proterozoic Geologic Era, two billion years ago
To introduce the concept of photosynthesis, microorganisms containing chloroplasts that can produce organic matter from carbon dioxide, water, and sunlight; and, give off oxygen as a waste product.
To present two models (nonbiological and biological) explaining the origin of Banded Iron Formation
To introduce the nonbiological model in which iron turns into rusty particles of iron oxide without the
influence of microorganisms; the iron is supplied by the interaction of hot sea water with magma erupting onto the ancient sea floor. Oxygen is dissolved in the sea water from an atmosphere rich in oxygen produced by terrestrial (on the land, rather than in the ocean) photosynthetic organisms.
To introduce the biological model in which iron from ocean water is turned into rusty sheaths of iron oxide around the cells of iron-oxidizing bacteria. The bacteria utilize oxygen produced by photosynthetic microorganisms that live in the ocean. Terrestrial photosynthesis is limited, so there is little or no oxygen in the atmosphere. The iron comes from weathering of rocks on the land surface, and magma erupting onto the sea floor. The iron-coated cells die and tons collect on the ocean floor.

Click to enlarge
Product Options


Ruth Deike
Rock Detective Geoscience Education
395 Deer Run Drive
Nellysford , VA 96080

Phone: 434-263-3737



© Copyright RealWeb Enterprises Ltd.
all rights reserved