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What is the Geologic time
scale?
The geological time scale is a system of
chronological measurement that relates
stratigraphy of time, and other earth scientist to
describe the timing and relationships between
events that have occurred throughout earth's
history
Time divisions
● Eons: The first and largest division of
geologic time
● Eras: The second division of geologic time
and each era has at least two periods.
● Periods: The third division of geologic time.
● Epoch: finer subdivisions of periods specially
for the Cenozoic period.
Example of geologic time
Archean eon
● the eon of first life
● oldest known rocks
● oldest known microfossils (single celled
organism resemble bacteria)
● first known plant (Algae)
Reasons behind the names
The odd names that we get for these period are
made up by geologist that name the time period
after fossils found for that time
Who invented the geological time
scale?
Nicolaus steno, who described two basic
principles then william produced the geologic
map
Question 1
What is largest time in the time scale?
a.epoch
b.era
c.eons
d.periods
e.years
Question 2
Who invented the geologic time map?
a.Nicolaus steno
b. Albert Einstein
c. William smith
d. Galileo Galilei
e. Willebrord Snell
Question 3
Why do you think the Geological time scale
important?