Timescale
Number of eras in Earth's geological history
What is, 4
Three types of fossils
Largest mass extinction known to man
What is permian-triassic event
Strata
What is, layers or series of rock in the ground
Relative dating
What is, the process of determining the age of an object/event based on the objects/events surrounding it
What is, 4.6 billion
Where fossils are found
What is, oceans, desserts, underground (all over the world)
Primary cause of the permian-jurassic extinction
What is, asteroid strike approx. 10-15km wide
Law of Superposition
What is, assuming the oldest layer is at the bottom, the youngest layer is at the top
Geological Timescale
What is, the history of Earth divided into Eons, eras, periods, and epochs
Cenozoic era, also known as
What is, the "Age of Mammals"
The study of fossils
What is, paleontology
Most catastrophic mass extinction
What is, permian-triassic extinction ("Great Dying")
If layer C goes through layer's A and B, this is the oldest layer (A starts from bottom)
What is, A
Uniformitarianism
What is, the principle that the geological events that occur today have occurred since Earth was formed.
Current epoch of Earth's geological history
What is, holocene
Fossils may be preserved in this tree resin
What is, Amber
Causes of mass extinction
What is, rapid climate change, volcanic activity, earthquakes, asteroid strike, reduced oxygen levels in oceans, rising sea levels,
Where one rock layer contains pieces of rock from the layer next to it
What is, an Inclusion
Radioactive Decay
The timescale uses these as boundaries between periods/eras etc.
What is, major extinction or origin of species
Suggested when a scientist finds an ancient coral reef organism on top of a mountain
What is, evidence that the area was once covered in a body of water or an ocean
Responsible for extinction of approx. 60% of marine life
What is, Ordovician Extinction
Difference between absolute dating and relative dating
What is, relative dating establishes if something is older or younger Thant something else, in a sequence. Absolute dating provides specific ages of an event/object.
Half-Life
what is, the length of time it takes for one half of the original isotope to decay