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Author: Nathan Lampson

This lesson provides a timeline of fossils while also discussing the different types, locations, and geology of various fossils.

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When the remains of a living thing are preserved a fossil is formed.  Paleontology is the study of prehistoric living things by examining fossils.


Timeline of Fossils:

Throughout the history of life, organisms whose remains were preserved in sedimentary rock have been fossilized.  This spiraling timeline depicts organisms that have existed throughout the geological timeline.  Layers of sedimentary rock are like layers of history.  The deeper the layer of sedimentary rock, the older the fossil.


Types of Fossils:

Molds and Casts

Petrified Fossils

Carbon Films

Trace Fossils

Preserved Remains


Geology of Fossils:

Fossils are found in layers of sedimentary rock.  Sedimentary rock is formed by layers of sediment that solidify over time.  The time of formation for the geology of a fossil site determine how old its fossils are.


Location of Fossils:

Fossils are found in areas where sedimentary rock formations are exposed.  Different fossil sites expose sedimentary rock from different ages.  One fossil site might contain fossils from the Jurassic period while another might contain fossils from the Cretaceous period.