Fossilisation showcase (1)

Click on a fossil Trilobita sp Cyclurus kehreri ERROR! Gastropoda indet. Asaphus sp. Brachiopoda indet. Ammonitidae indet. Terebratula vulgaris
The preservation of fossils

Fossils (Petrifactions) are remains of plants and animals from earlier times preserved in rock. The rock is made from sediments or chemical precipitations in water, in deserts, in caves etc. Dead animals and plants decompose quickly. Usually only the hard parts are preserved as fossils (shells, bones, teeth). They must be buried quickly and become protected against air (oxygen), micro organisms and larger animals. Under unusual conditions soft parts or their impressions may be preserved, as in e.g. permafrost, in amber or in unusually stagnant water without oxygen

Part and counterpart.
If you break a stone in two and find a fossil inside, one part will look like an impression. "The impression" is called the counterpart. The fossil is only a thin shell and the shell itself may be stuck on the counterpart, while the part with the positive relief, may lack the original shell. Different ways of preservation. List of contents in the fossilisation showcase (1)

[Norsk tekst]
Publisert 18. mai 2011 16:00