Download Fossil Class Notes

Fossils
Fossil – the remains, imprints, or traces of once-living organisms, usually preserved in rock, that
tell us when, where, and how those organisms lived.
Fossil Preservation: Necessary Conditions:
The body of a dead organism must be protected from scavengers and microorganisms. You
need:
● ____________________ (sediments from floods, landslides, etc.)
● ____________________ (bones, shells, or teeth)
●
____________________ Fossils typically do not withstand the heat and pressure
involved in forming igneous and metamorphic rocks. Limestone, Shale, Sandstone are
examples
In Virginia, fossils can be found in these physiographic provinces:
________________________
________________________
________________________
Virginia contains fossils from these eras:
________________________
________________________
________________________
Types of Fossils:
Petrified Fossils - Some or all of the original materials in the remains have been replaced by
minerals. Example: _____________________________
Carbonaceous Film - The tissues of most organisms are made of compounds that contain
carbon.
Molds and Casts –
● Mold – the void left by the decay of an organism.
● Cast – if other sediments fill the mold and solidify then you have a cast.
Original Remains – actual body parts are preserved: ice men, mammoths, tar pits
Trace Fossils - Fossilized tracks or other evidence of animal activity. Coprolites, Dino Tracks
Index fossil – species that existed on Earth for a relatively __________ period of time, were
________________, were ______________ geographically. Good for identifying ages of rocks.
Fossils also indicate the ______________________ of an area long ago.
Most Virginia fossils are of ________________________________.