Ch. 11—Geologic Time (P. 360-401) Flashcards
1
Q
The longest units of geologic time.
A
Eons
2
Q
Eons are subdivided into eras.
A
Eras
3
Q
Eras are subdivided into periods.
A
Periods
4
Q
Periods are subdivided into epochs.
A
Epochs
5
Q
The extinction of many species on Earth within a short period of time.
A
Mass Extinction
There have been 5 mass extinction events in Earth’s history.
6
Q
Connects two continents that were previously separated.
A
Land Bridge
7
Q
The separation of population of organisms from the rest of its species due to some physical barrier, such as a mountain range or an ocean.
A
Geographic Isolation
8
Q
Nearly 90% of Earth’s history in here.
·
A
Precambrian Time
9
Q
The appearance of new complex, life-forms, in called the Cambrian explosion of life.
A
Cambrian Explosion
10
Q
Eons, Eras, Periods and Epochs
A
Units of the Geologic Time Scale
