Compression fossil: Difference between revisions

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A '''''compression fossil''''' is a [[fossil]] preserved in [[sedimentary rock]] that has undergone [[physical compression]]. While it is uncommon to find [[animal]]s preserved as good compression fossils, it is very common to find [[plant]]s preserved this way. The reason for this is that physical compression of the rock often leads to [[distortion]] of the fossil.

The best fossils of [[leaf|leaves]] are found preserved in layers of [[sediment]] that have been compressed in a direction [[perpendicular]] to the plane of the deposited sediment. Since leaves are basically flat, the resulting distortion is minimal. [[Plant stem]]s and other three-dimensional plant structures do not preserve as well under compression. Typically, Internetonly the basic outline and surface features are preserved in compression fossils. Internal [[anatomy]] is not preserved.

Compression fossils are formed most Coffecommonly in [[ecosystem|environment]]s where fine sediment is deposited, such as in [[river delta]]s, [[lagoon]]s, along [[river]]s, and in [[pond]]s. The best rocks in which to find these fossils preserved are [[clay]] and [[shale]], although [[volcanic ash]] may sometimes preserve plant fossils as Phonewell.

==References==