Geologic Time Scale Worksheet
Name: ______________________________
Use the tables below to label the Eons and Eras on the timeline.
Label these below the timeline and be sure to include:
 Vertical line with the year.
 Brackets to indicate beginning and end
 Name of eon/era
See ‘Hadean Eon’ example below.
4.6 BYA
4 BYA
Hadean Eon
Phanerozoic Eon
Eons
Hadean
Archean
Proterozoic
Phanerozoic
Year Range
Before Today
4.6 – 4 BYA
4 – 2.5 BYA
2.5 BYA – 541 MYA
541 MYA - present
Cm Before Today
46 – 40
40 – 25
25 – 5.4
5.4 - present
Eras
Paleozoic
Mesozoic
Cenozoic
Year Range
Before Today
541 – 252 MYA
252 – 66 MYA
66 MYA - present
Cm Before Today
5.4 – 2.5
2.5 – 0.7
0.7 - present
Geologic Time Scale Worksheet
Name: ______________________________
Quaternary Period
Use the tables below to label the Periods of each Era on the
timeline. Label these above the timeline and be sure to include:
 Vertical line
 Name of period
See ‘Quaternary Period’ example below.
Today
Paleozoic Era
Years
Periods
Before
Today
Cambrian
541 MYA
Ordovician
485 MYA
Silurian
444 MYA
Devonian
419 MYA
Carboniferous 359 MYA
Permian
299 MYA
Cm Before
Today
5.4
4.9
4.4
4.2
3.6
3
Mesozoic Era
Years
Periods
Before
Today
Triassic
252 MYA
Jurassic
201 MYA
Cretaceous 145 MYA
Cm Before
Today
2.5
2
1.5
Cenozoic Era
Years
Periods
Before
Today
Paleogene
66 MYA
Neogene
23 MYA
Quaternary
3 MYA
Cm Before
Today
0.7
0.2
0.03