there are different kinds of fossils petrified molds and casts carbon film trace preserved remains
Post on 02-Jan-2016
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There are different kinds of fossils
• Petrified• Molds and casts• Carbon film• Trace• Preserved remains
Petrified Fossils
• Forms when water that is rich in minerals seeps into spaces in cells and then over time evaporates out.
• When the water evaporates it leaves the minerals behind.
• The minerals turn harden and turn the organism to stone
Molds and casts
• A mold is a hollow area in sediment where an organism used to be
• A cast is a copy of the shape of the organism
Cast Fossil
Mold fossil
Mold Cast
Carbon Film
• The organism leaves an extremely thin coating of carbon on a rock
• Gases escape from the sediment and leave carbon behind
Trace Fossils
• Provides evidence of animal activity.• Example:– Footprint / Caves– Poop
Preserved Remains (body fossils)
• Some processes preserve the remains of organisms with little or no change– Tar pits– Amber– Freezing
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