Name___________________________
Date________________
Partner:__________________________
PS/ES Lab Per______
Mr. Landsman
LAB: Geologic Timeline
Background: The geologic time scale is depicted in the center section of your ESRT. It
is difficult, however, to express the important events in Earth’s history in a linear fashion
on a page of that size. Consequently, the ESRT compress the Precambrian (~4 billion yrs)
into an inch strip (bottom) and expand the Phanerozoic (~540 million years) to fill out the
page. This provides room to note the important events in geologic time, but may confuse
the student trying to understand the concept of linear geologic time. SO…you will create a
time line TO SCALE on a paper that lends itself well to depicting L O N G time
passage.
Objective: Students will attain a sense of geologic time from a linear representation.
Procedure:
1. Measure 10 cm from one end of the tape and draw a line across the tape. Write your
names in the 10 cm space
2. Label the line (on your name side) “NOW”. All measurements will be made from
this line.
3. Measuring from the “NOW” line, mark off 1 meter intervals. At each interval, make
a line across the tape and label the lines as increasing Billions of years. Ex: 1
billion, 2 billion etc
4. Measuring from the NOW line, plot the events listed in the table on the next page.
Plot lines on the tape. Label each line with the age and event from the table.
BIG QUESTION: How much time is represented by cm, mm, m ????
Conclusions:
1. Please share your personal experience as you became more enlightened in
understanding geologic time. What surprised you? What turned out the way you
expected? Does this scale conflict your previous understanding of Earth’s history?
Explain. Does the time line (based on scientific evidence and theory) conflict with
any personal beliefs regarding Earth’s history? Explain
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
2. Which two consecutive events from the table are separated by the longest duration of
time? About how many years separate the events?
________________________________________________________________________
_________________________________________________________________________
3. From your ESRT, determine the duration and timeline scale length of the following:
a) Archean Eon _______________
_________________
b) Proterozoic Eon______________
_________________
c) Paleozoic Era________________
_________________
d) Mesozoic Era________________
_________________
e) Cenozoic Era________________
_________________
4. During what percentage of Earth’s history did Dinosaurs roam the Earth
(ESRT).___________________________________________________
LAB: Geologic Timeline
Geologic Eons, Periods, Epochs
Number of
years ago
11 thousand
1.6 million
3.5 million
24 million
65 million
142 million
200 million
206 million
225 million
251 million
290 million
362 million
418 million
425 million
443 million
490 million
544 million
1.2 billion
3.5 billion
4.6 billion
Event
End of last ice age
Beginning of Pleistocene Epoch
Earliest evidence of humanoids
Earliest grasses
End of Mesozoic / Beginning of Cenozoic /
MASSIVE EXTINCTION
Beginning of Cretaceous
First mammal fossils
Beginning of Jurassic
First birds
End of Paleozoic / Beginning of Mesozoic /
MASSIVE EXTINCTION
Beginning of Permian
Beginning of Carboniferous / End of Devonian /
MASSIVE EXTINCTION
Beginning of Devonian / End of Silurian
Earliest life on land
Beginning of Silurian / End of Ordovician /
MASSIVE EXTINCTION
Beginning of Ordovician / End of Cambrian
End of Precambrian
First animal fossils (marine)
Oldest rocks (in original form)
Origin of Earth