Types of Fossils
Abundant, widespread and composed of a lot of different species and are used to date rock ages around the world.
What are some characteristics of Index Fossils and what are they used for?
The division that comes after eons, eras...
What are periods?
The Paleozoic Era received this nickname from the creatures that dominated it
What is the Age of Invertebrates?
65 million years ago, the planet and its life were devastated by this natural disaster
What is an asteroid impact?
The periods of the Cenozoic Era are uniquely divided into these smaller categories.
What are epochs?
This fossil dissolved out of the rock and left a hollow depression that shows the original shape and surface.
What is a mold?
A process in which an unstable atomic nucleus loses energy, useful for dating rocks.
What is radioactive decay?
The extinction event informally known as "The Great Dying," in which 90% of species were lost
What is the Permian-Triassic extinction?
Humid and tropical
What was the climate of the Mesozoic?
Scientists are concerned by this ongoing mass extinction
What is the Holocene extinction?
A fossil that contains none of a creature's remains, but rather indirect evidence of its existence
What is a trace fossil?
"Cold Oysters Seldom Develop Many Precious Pearls, Their Juices Congeal Too Quickly"
What is the mnemonic for remembering the periods order?
These two geologic eons are divided by the beginning of the Paleozoic Era
What is the Proterozoic and Phanerozoic?
Laurasia broke off of Pangaea between these periods
What are the Triassic and Jurassic?
Our current Canadian landscape was mostly shaped by this event during the Pleistocene epoch
What is the Ice Age?
A fossil of this type was replaced by minerals. A fossil of this other type remained the same throughout the fossilization process.
What is an altered and unaltered fossil?
This ratio of original:new substance indicates that it has gone through 2 half-lives of decay
What is a 1:3 ratio?
The Appalachian mountain range formed in this period
What is the Devonian?
An ocean that formed in the Cretaceous Period
What is the South Atlantic Ocean?
This plant appeared and spread in 35 Ma in the Epoch Oligocene, in the Period Paleogene.
When does grass and grasslands first appear?
A fossil with a thin film resembling a silhouette.
What is a carbonaceous film?
Evidence of this process in the surrounding rock indicates whether an igneous intrusion is younger
What is contact metamorphism?
The three mass extinctions of the Paleozoic Era
What are the Ordovician, late Devonian, and Permian-Triassic?
The cone-bearing plants that dominated the planet were eventually superceded by this modern type of plant
What are flowering plants?
In 2004, scientists agreed to split this former period into the Paleogene and Neogene
What is the Tertiary period?