Detailed description on the chronology of the earth. reported are the very good source of information

1. Jason John V. Tabujara BSEdGS IV
STA
RT

2. WHAT IS A GEOLOGIC
TIME SCALE?
System of chronologic
measurement relating
to stratigraphy to time
that is used by
geologist and other
earth scientists

3. INTRODUCTION TO
CONCEPT:
The period is the basic unit of geological
time in which a single type of rock system
is formed. Two or more periods comprise
a geological Era. Two or more Eras form
an Eon, the largest division of geologic
time. Some periods are divided into
epochs.
The major periods in the geologic history
of the Earth are (mya=million years ago):

4. INTRODUCTION TO
CONCEPT:
Eon
Era
Period
Epoch
Period
Era Period

5. Hadean, Archean and
Proterozoic Eons

6. PRECAMBRIAN
Hadean Eon
4.6 to 3.9 billion
years ago
“Rockless Eon" -
The solidifying of
the Earth's
continental and
oceanic crusts.
Archeozoic Eon
(Archean)
3.9 to 2.5 billion
years ago
"Ancient Life"
The first life forms
evolve
Proterozoic Eon
2.5 billion years
ago to 540 mya
*multi-celled, animals
appear, including
sponges.
*Single
supercontinent called
Rodinia.
*First multicellular
life: colonial algae
and soft-bodied
invertebrates appear.

7. Paleozoic Era

8. PHANEROZOIC EON
Paleozoic Era:
The Paleozoic is bracketed by two of the
most important events in the history of
animal life.
1. Multicellular animals went dramatic
diversity explosion
2. Largest Mass extinction of mostly
90% of marine organisms

9. PALEOZOIC ERA
Cambrian Period
"The Age of Trilobites"
540 to 500 mya

10. PALEOZOIC ERA
Ordovician Period
505 to 438 mya

11. PALEOZOIC ERA
Silurian Period
438 to 408 mya

12. PALEOZOIC ERA
Devonian Period
"The Age of Fishes"
408 to 360 mya

13. PALEOZOIC ERA
Carboniferous
Mississippian Period
360 to 325 mya

14. PALEOZOIC ERA
Carboniferous
Pennyslvanian Period
325 to 280 mya

15. PALEOZOIC ERA
Permian Period
"The Age of Amphibians"
280 to 248 mya

16. Mesozoic Era

17. PHANEROZOIC EON
Mesozoic Era:
Many of the Old life forms had just gone
extinct in the Permian Extinction, the
world’s largest mass extinction.
Depleted state was followed by an
explosion of new life forms such as
dinosaurs, mammals, birds and
flowering plants

18. MESOZOIC ERA
Triassic Period
248 to 208 mya

20. MESOZOIC ERA
Jurassic Period
208 to 146 mya

22. MESOZOIC ERA
Cretaceous Period
146 to 65 mya

24. Cenozoic Era

25. PHANEROZOIC EON
Cenozoic Era:
The most recent Era of the three major
subdivisions of animal history.
Also called as the Age of Mammals
65.5 million years ago to present