Fossilization Flashcards
What are fossils?
Preserved remnants of organisms including TISSUE, BONES, TEETH, and SHELLS
IF IT PRESERVES IT CAN BECOME A FOSSIL IN TIME
How do you preserve a fossil?
IT NEEDS TO BE BURIED
What is considered a fossil?
Any fossil that is older than 10,000 years old
If it is younger, then it is considered recent and not yet a fossil
What parts of an animal are most likely going to be preserved? What might be lost?
Preserved : Tusks, Bones, Skulls
Not preserved: Fur, Flesh, and any soft internal anatomy
Why would hard parts be more likely to be preserved than soft parts?
Hard parts are made of minerals like bones and shells
What are the 3 common minerals in fossils that make preservation more likely?
CALCITE (3 Hardness)
QUARTZ (7 Hardness)
APATITE (5 Hardness)
What is mostly preserved with the mineral calcite?
Seashells
NEARLY ALL SEASHELLS FOUND IN THE OCEAN ARE MADE OF THE MINERAL CALCITE
What is mostly preserved with the mineral quartz?
Trees and wood
Petrified wood consists of primarily quartz that has replaced the original wood
What is apatite?
Mineral of bones and teeth, it is the calcium-based mineral that makes teeth and bone stronger
What are the 6 different ways in which a fossil may be preserved?
1) Unaltered Remains
2) Permineralization
3) Replacement
4) Cast
5) Carbonization
6) Trace Fossils
What are unaltered remains?
Fossils that have not changed much since the death of the organism
Can be due to being encased in amber or frozen in ice
What do the unaltered remains of shells look like?
Will be shiny and pearly as when the animal was alive
Still be considered unaltered even if the soft tissue has decayed
What is the process of permineralization?
When a fossil’s vacant space has been filled-in with minerals
NEW MINERALS COME IN BUT NOTHING IS REMOVED
EX. Fossilized bone or Petrified wood
What is important to note about the fossilization of calcite?
Any fossil made of the mineral calcite will dissolve in acidic rain water
What happens when a fossil dissolves?
It leaves behind a mold, which can be filled in one of two ways
What is the process of replacement?
If there is a mold of a fossil, new minerals will fill in this mold
IT PRESERVES THE FOSSIL’S FINE DETAIL
What is the difference between replacement and permineralization?
Replacement will completely remove anything original and leave behind new minerals
Permineralization will fill in VACANT SPACE of the fossil, adding minerals AS WELL AS KEEPING the original contents of the fossil (NOTHING ORIGINAL IS REMOVED
What is the process of cast?
Sediment like sand or mud fills in the mold of a fossil, the resulting fossil is called a cast
What is the different between replacement and cast?
Replacement is filling in the mold with MINERALS
Cast is filling in the mold with SEDIMENT
What is the process of Carbonization?
Fossil is preserved as a thin film of carbon on the surface of a rock
Carbon comes from the plant or animal
Why is there black film for the fossils of carbonization?
Carbonization preserves carbon remains of soft-bodied animals and plants, this is what makes up the black film
What are trace fossils?
What kind of things can be considered trace fossils?
Fossilized BEHAVIOR
Can consist of impressions, burrows, tubes, tunnels, fossilized poop, and track ways
How are trace fossils unique compared to the other fossilization methods?
They do not preserved the animal itself and can sometimes be ambiguous in their origin
BUTTT their behavior may be known, but not the maker
What are coporolites?
Deposits left behind by animals, ESSENTIALLY FOSSILIZED POOP
ALSO CONSIDERED TRACE FOSSILS
