SES 4UI: Geologic Time Activity
Name: _________________________________
Date: ________________________________
1 sheet of 11” x 17” paper, 2 sheets of 8’ x 11” paper, Ruler, Calculator, description of
Geological Eras and Periods, Pencil crayons
Materials:
Name of
Geological Eon
Name of
Geological Era
Time Period
(million years ago)
Length on Time Line
(1cm = 100 million years)
Phanerozoic
Cenozoic
Mesozoic
Paleozoic
65 to present
248 to 65
0.65 cm
1.83 cm
4600 to 3800
8.00 cm
Proterozoic
Archaean
Hadean
Procedure A: Geological Eons and Eras from the Hadean to the Present
1)
2)
3)
4)
5)
6)
Tape the 8 x 11 sheet to the end of the 11 x 17 sheet. Orient your new 11 x 25
11 x 17
sheet as seen at right.
sheet
Draw a 46 cm line along the left hand side of the page (see the diagram at
right). The line should be 4 - 5 cm thick (the “line” should be hollow so that
information can be added inside.
Each cm on the line represents 100 million years. Subdivide the line to show
8 x 11
the relative length of each geological time period from the Cenozoic (at the top)
sheet
to the Hadean (at the bottom).
Use the worksheet up above to show all of your calculations (complete the
unshaded section of the chart). Use the data from the worksheet to subdivide
your line accurately.
Label each section of your time line with the correct time period. Use coloured pencils to
shade each section of the line.
With the remaining space on the right hand side of the page – write descriptive sentences
to explain major geological, evolutionary and biological events that occurred at each era or
eon (example – the oldest fossils, the formation of an oxygen atmosphere). Sometimes
major events occur at the transition between eras (example – major extinction event or
meteorite strike). DO NOT GO INTO GREAT DETAIL ON EVENTS OCCURING IN THE
PHANEROZOIC ERA AS THEY WILL BE INCLUDED IN THE NEXT TIME LINE.
Procedure B: Geological Eras and Periods from the Cambrian to the Present
(Phanerozoic).
1)
2)
3)
On the reverse side of your sheet, draw a 54.3 cm line along the left hand side of the page
that is 4 - 5 cm thick.
Each cm on the line represents 10 million years. Subdivide the line to show the relative
length of each geological period from the Quaternary (at the top) to the Cambrian (at the
bottom).
Use the worksheet below to show all of your calculations (complete the unshaded section
of the chart). Use the data from the worksheet to subdivide your line accurately.
4)
5)
Label each section of your time line with the correct time period. Use coloured pencils to
shade each section of the line.
With the remaining space on the right hand side of the page – write descriptive sentences
to explain:
a) major geological events – perhaps a discussion of the arrangements, names and
positions of continents (ex. The break-up of Pangaea), or the cosmological cause of a
major extinction (a meteorite impact)
b) evolutionary and biological events - (example – appearance of mammals, extinction
of species).
c) atmospheric or hydrospheric (oceanic) events – there is not as much change in the
Phanerozoic
* Sometimes major events occur at the transitions between periods (example – dinosaur
extinction event)
Name of
Geological Eon
Name of
Geological Era
Name of
Geological Period
Time Period
(million years ago)
Length on Time
Line (1cm = 10
million years)
Length on Geological
Clock
Phanerozoic
Cenozoic
Quaternary
1.8 to present
0.18 cm
1.8/191.7 = 0.009 h or
1.8/3.2 = 0.56 min
Tertiary
Cretaceous
Jurassic
Triassic
Permian
Carboniferous
Devonian
Silurian
Ordovician
Cambrian
65 to 1.8
144 to 65
6.32 cm
7.90 cm
Mesozoic
Paleozoic


Your mark will be based on the amount of detail, the accuracy and the neatness of your
time line. (Remember to include titles and your name)
geological time is further subdivided into epochs and ages (but we will focus on the
major events that occurred in each period or era.
OPTION: Procedure C: Create a Geological clock. (Actually create two!)
1 sheet of 11” x 17” paper, 2 sheets of 8’ x 11” paper, Protractor, Calculator, description
of Geological Eras and Periods, Pencil crayons
Materials:
Since a circle has 360°, a single degree equals (4.6 billion years ÷ 360) approximately 12.8 million
years. A 1-hour segment (or 15° segment on the clock) represents 4.6 billion years ÷ 24 = 191.7
million years.
Name of
Geological Eon
Name of
Geological Era
Time Period
(million years ago)
Phanerozoic
Cenozoic
65 to present
Mesozoic
Paleozoic
248 to 65
Proterozoic
Archaean
Hadean
4600 to 3800
Length on Geological Clock in
degrees on a circle (pie graph)
(1° = 12.8 million years)
Length on Geological Clock in hours
on a 24-hour clock
(1 hour =
191.7 million years) (1 minute = 3.2
million years)
65/191.7 = 0.34 hours or
65/3.2 = 20.3 minutes
800/12.8 = 4.17 hours or
4 hours 10.2 minutes
800/191.7 = 4.17 hours
or 4 hours 10.2 minutes
Name of
Geological
Era
Name of
Geological
Period
Time Period
Length on Geological Clock in
(million years ago) degrees on a circle (pie graph)
(1° = 12.8 million years)
Length on Geological Clock in
hours on a 12-hour clock
(1 hour = 191.7 million years)
(1 minute = 3.2 million years)
Cenozoic
Quaternary
1.8 to present
0.18 cm
1.8/191.7 = 0.009 h or
1.8/3.2 = 0.56 min
Tertiary
Cretaceous
Jurassic
Triassic
Permian
Carboniferous
Devonian
Silurian
Ordovician
Cambrian
65 to 1.8
144 to 65
6.32 cm
7.90 cm
Mesozoic
Paleozoic
Procedure C: Geological Time Clock
1)
2)
3)
4)
On the bottom of this sheet there are two unlabelled clock faces.
You have two clock faces. One represents a.m. and the other represents p.m.
Each hour on the clock represents 191.7 million years, each minute – 3.2 million years.
Show the length of each time period (eon, era or period) on the clocks. Some eons or eras will
extend from one clock to the other.
5) Shade each era in a different colour (No descriptions are required)
The Geological Time Scale
Phanerozoic Eon
(543 mya to present)
Cenozoic Era
(65 mya to today)
Quaternary (1.8 mya to today)
Holocene (10,000 years to today)
Pleistocene (1.8 mya to 10,000 yrs)
Tertiary (65 to 1.8 mya)
Pliocene (5.3 to 1.8 mya)
Miocene (23.8 to 5.3 mya)
Oligocene (33.7 to 23.8 mya)
Eocene (54.8 to 33.7 mya)
Paleocene (65 to 54.8 mya)
Mesozoic Era
(248 to 65 mya)
Cretaceous (144 to 65 mya)
Jurassic (206 to 144 mya)
Triassic (248 to 206 mya)
Paleozoic Era
(543 to 248 mya)
Permian (290 to 248 mya)
Carboniferous (354 to 290 mya)
Pennsylvanian (323 to 290 mya)
Mississippian (354 to 323 mya)
Devonian (417 to 354 mya)
Silurian (443 to 417 mya)
Ordovician (490 to 443 mya)
Cambrian (543 to 490 mya)
Tommotian (530 to 527 mya)
Precambrian Time
(4,500 to 543 mya)
Proterozoic Era
(2500 to 543 mya)
Neoproterozoic (900 to 543 mya)
Vendian (650 to 543 mya)
Mesoproterozoic (1600 to 900 mya)
Paleoproterozoic (2500 to 1600 mya)
Archaean
(3800 to 2500 mya)
Hadean
(4500 to 3800 mya)
Hadean Era
This era begins with the formation of the Solar System and Earth, outgassing of first atmosphere and oceans, bombardment by left-over
planetessimals and debris. The name says it all; a hellish period lasting some 760 million years, when the Earth was subject to frequent
bombardment by comets, asteroids, and other planetary debris. At one point, early in this era the moon was formed when a Mars-sized body
struck the original Earth, pulverizing both. Yet incredibly, the first primitive life emerged even at this early stage. This was an era
characterized by extensive volcanism and formation of first continents. By the end of the Hadean, the Earth had an atmosphere
(unbreathable to most organisms today), and oceans filled with prokaryote life evolution
Archean Era
Lasting more than twice as long as the Phanerozoic eon, the Archean was a time when diverse microbial life flourished in the primordial
oceans, and the continental shields developed from volcanic activity. The reducing (anaerobic) atmosphere enabled archea (anaerobic
microbes) to develop, and plate tectonics followed a regime of continental drift different to that of the Proterozoic and later. During this era,
one type of organism, the Cyanobacteria (blue-green algae) produced oxygen as a metabolic by-product; the eventual build-up of this highly
reactive gas was to eventually prove fatal to many life-forms, and converted the atmosphere from.
Proterozoic Era
The Proterozoic, which lasted even longer than the Archean Era, saw the atmosphere changes from reducing to
oxygenated, driving the original anaerobic inhabitants of the Earth into a few restricted anoxic refuges and enabling the
rise of aerobic life (both prokaryote and the more complex eukaryotic cell, which requires the high octane boost that
oxygen enables.) Stromatolites (colonial cyanobacteria), which had appeared during the Archean, were common. The
modern regime of continental drift began, and saw the formation of supercontinent of Rodinia, and several extensive ice
ages. Late in the Proterozoic a runaway icehouse effect meant that the preceding warm conditions were replaced by a
"Snowball Earth" with ice several kilometers deep covering the globe. Warming conditions saw the short-lived Edicarian biota and finally
the appearance of first metazoa.
Paleozoic Era
Early in the 300 million year history of the Paleozoic, atmospheric oxygen reached its present levels, generating the ozone
shield that screens out ultraviolet radiation and allows complex life to live in the shallows and finally on land. This era
witnessed the age of invertebrates, of fish, of tetrapods, and (during the Permian) reptiles. From the Silurian on, life
emerged from the sea to colonize the land, and in the later Paleozoic pteridophyte and later gymnospermous plants
flourished. The generally mild to tropical conditions with their warm shallow seas were interspersed with Ordovician and
Permo-Carboniferous ice ages. Towards the end of the Paleozoic the continents clustered into the supercontinent of
Pangea, and increasingly aridity meant the end of the great Carboniferous swamps and their unique flora and fauna. The Paleozoic was
brought to an end by the end Permian mass-extinction, perhaps the most severe extinction the planet has seen.
Mesozoic Era
Lasting little more than half the duration of the Paleozoic, this was a spectacular time. The generalized archosaurian
reptiles of the Triassic gave way to the dinosaurs, a terrestrial megafauna the like of which the Earth has not seen
before or since. While dinosaurs dominated the land, diverse sea-reptiles ruled the oceans, and invertebrates,
especially ammonites, were extremely diverse. Pterosaurs and later birds took to the sky. Mammals however
remained small and insignificant. Climatic conditions remained warm and tropical worldwide. The supercontinent
of Pangea broke up into Laurasia and Gondwana, with different dinosaurian faunas evolving on each. During this
era modern forms of corals, insects, new fishes and finally flowering plants evolved. At the end of the Cretaceous
period the dinosaurs and many other animals abruptly died out, quite likely the result of an asteroid impact and associated extensive
volcanism (acid rain)
Cenozoic Era
With the extinction of the dinosaurs and the end of the Mesozoic, the mammals swiftly inherit the Earth. Archaic
mammals co-existed with birds and modern reptiles and invertebrates. The current continents emerged, and the
initial tropical conditions were replaced by a colder drier climate, possibly caused by the Himalayan uplift. The
appearance of grass meant the rise of grazing mammals, and the cooler drier world allowed modern mammalian
groups to evolve, along with other lineages now extinct and a few archaic hold-overs. Among the newcomers were
the anthropoid apes that culminated in the australopithecine hominids of Africa. Decreasing temperatures and a
polar landmass of Antarctica resulted in a new Ice Age. Most recently, in the blink of an eye geologically speaking,
this era saw the rise of Man (Homo erectus, Neanderthal and Cro Magnon) and use of stone tools and fire, the extinction of Megafauna, and
civilization and human activities that have transformed the globe, but at a cost of great environmental destruction.
Paleozoic Era
543 to 248 Million Years Ago
The Paleozoic is bracketed by two of the most important events in the history of
animal life. At its beginning, multicelled
animals underwent a dramatic "explosion"
in diversity, and almost all living animal
phyla appeared within a few millions of
years. At the other end of the Paleozoic, the
largest mass extinction in history wiped out
approximately 90% of all marine animal
species. The causes of both these events are
still not fully understood and the subject of
much research and controversy. Roughly
halfway in between, animals, fungi, and
plants alike colonized the land, the insects
took to the air, and the limestone shown in
this picture was deposited near Burlington,
Missouri.
The Paleozoic took up over half of the Phanerozoic, approximately 300 million years. During the Paleozoic
there were six major continental land masses; each of these consisted of different parts of the modern
continents. For instance, at the beginning of the Paleozoic, today's western coast of North America ran east-west
along the equator, while Africa was at the South Pole. These Paleozoic continents experienced tremendous
mountain building along their margins, and numerous incursions and retreats of shallow seas across their
interiors. Large limestone outcrops, like the one shown above, are evidence of these periodic incursions of
continental seas.
Many Paleozoic rocks are economically important. For example, much of the limestone quarried for building
and industrial purposes, as well as the coal deposits of western Europe and the eastern United States, were
formed during the Paleozoic.
The Permian
290 to 248 Million Years Ago
The Permian period lasted from 290 to 248 million years ago and was the last period of the Paleozoic Era. The
distinction between the Paleozoic and the Mesozoic is made at the end of the Permian in recognition of the
largest mass extinction recorded in the history of life on Earth. It affected many groups of organisms in many
different environments, but it affected marine communities the most by far, causing the extinction of most of
the marine invertebrates of the time. Some groups survived the Permian mass extinction in greatly diminished
numbers, but they never again reached the ecological dominance they once had, clearing the way for another
group of sea life. On land, a relatively smaller extinction of diapsids and synapsids cleared the way for other
forms to dominate, and led to what has been called the "Age of Dinosaurs". Also, the great forests of fern-like
plants shifted to gymnosperms, plants with their offspring enclosed within seeds. Modern conifers, the most
familiar gymnosperms of today, first appear in the fossil record of the Permian. In all, the Permian was the last
of the time for some organisms and a pivotal point for others, and life on earth was never the same again.
The global geography of the Permian included massive areas of land and water. By the beginning of the
Permian, the motion of the Earth's crustal plates had brought much of the total land together, fused in a
supercontinent known as Pangea. Many of the continents of today in somewhat intact form met in Pangea (only
Asia was broken up at the time), which stretched from the northern to the southern pole. Most of the rest of the
surface area of the Earth was occupied by a corresponding single ocean, known as Panthalassa, with a smaller
sea to the east of Pangea known as Tethys.
Models indicate that the interior regions of this vast continent were probably dry, with great seasonal fluctuations, because
of the lack of the moderating effect of nearby bodies of water, and that only portions received rainfall throughout the year.
The ocean itself still has little known about it. There are indications that the climate of the Earth shifted at this time, and
that glaciation decreased, as the interiors of continents became drier.
The Carboniferous
354 to 290 Million Years Ago
The Carboniferous Period occurred from about 354 to 290 million years ago during the late Paleozoic Era. The
term "Carboniferous" comes from England, in reference to the rich deposits of coal that occur there. These
deposits of coal occur throughout northern Europe, Asia, and midwestern and eastern North America. The term
"Carboniferous" is used throughout the world to describe this period, although this period has been separated
into the Mississippian (Lower Carboniferous) and the Pennsylvanian (Upper Carboniferous) in the United
States. This system was adopted to distinguish the coal-bearing layers of the Pennsylvanian from the mostly
limestone Mississippian, and is a result of differing stratigraphy on the different continents.
Carboniferous Forest : The Carboniferous Period is famous for its vast coal swamps, such as the one depicted here. Such swamps
produced the coal from which the term "Carboniferous", or "carbon-bearing" comes.
In addition to having the ideal conditions for the beginnings ofcoal, several major biological, geological, and
climatic events occurred during this time. One of the greatest evolutionary innovations of the Carboniferous was
the amniote egg, which allowed for the further exploitation of the land by certain tetrapods. The amniote egg
allowed the ancestors of birds, mammals, and reptiles to reproduce on land by preventing the desiccation of the
embryo inside. There was also a trend towards mild temperatures during theCarboniferous, as evidenced by the
decrease in lycopods and large insects and an increase in the number of tree ferns.
Geologically, the Late Carboniferous collision of Laurussia (present-day Europe and North America) into
Godwanaland (present-day Africa and South America) produced the Appalachian mountain belt of eastern
North America and the Hercynian Mountains in the United Kingdom. A further collision of Siberia and eastern
Europe created the Ural Mountains.
The stratigraphy of the Lower Carboniferous can be easily distinguished from that of the Upper Carboniferous. The
environment of the Lower Carboniferous in North America was heavily marine, when seas covered parts of the
continents. As a result, most of the mineral found in Lower Carboniferous is limestone, which are composed of the
remains of crinoids, lime-encrusted green algae, or calcium carbonate shaped by waves. The North American Upper
Carboniferous environment was alternately terrestrialand marine, with the transgression and regression of the seas caused
by glaciation. These environmental conditions, with the vast amount of plant material provided by the extensive coal
forests, allowed for the production of coal. Plant material did not decay when the seas covered them and pressure and heat
eventually built up over the millions of years to transform the plant material to coal.
The Silurian
443 to 417 Million Years Ago
The Silurian (443 to 417 million years ago) was a time when the Earth underwent considerable changes that had
important repercussions for the environment and life within it. The Silurian witnessed a relative stabilization of
the earth's general climate, ending the previous pattern of erratic climatic fluctuations. One result of these
changes was the melting of large glacial formations. This contributed to a substantial rise in the levels of the
major seas.
Coral reefs made their first appearance during this time, and the Silurian was also a remarkable time in the
evolution of fishes. Not only does this time period mark the wide and rapid spread of jawless fish, but also the
highly significant appearances of both the first known freshwater fish as well as the first fish with jaws. It is
also at this time that our first good evidence of life on land is preserved, including relatives of spiders and
centipedes, and also the earliest fossils of vascular plants.
The Ordovician
490 to 443 Million Years Ago
The Ordovician period began approximately 510 million years ago, with the end of the Cambrian, and ended
around 445 million years ago, with the beginning of the Silurian. At this time, the area north of the tropics was
almost entirely ocean, and most of the world's land was collected into the southern super-continent Gondwana.
Throughout the Ordovician, Gondwana shifted towards the South Pole and much of it was submerged
underwater.
The Ordovician is best known for the presence of its diverse marine invertebrates, including graptolites,
trilobites, brachiopods, and the conodonts (early vertebrates). A typical marine community consisted of these
animals, plus red and green algae, primitive fish, cephalopods, corals, crinoids, and gastropods. More recently,
there has been found evidence of tetrahedral spores that are similar to those of primitive land plants, suggesting
that plants invaded the land at this time.
From the Early to Middle Ordovician, the earth experienced a milder climate in which the weather was warm
and the atmosphere contained a lot of moisture. However, when Gondwana finally settled on the South Pole
during the Late Ordovician, massive glaciers formed causing shallow seas to drain and sea levels to drop. This
likely caused the mass extinctions that characterize the end of the Ordovician, in which 60% of all marine
invertebrate genera and 25% of all families went extinct.
The Cambrian Period
543 to 490 Million Years Ago
The Cambrian Period marks an important point in the history of life on earth; it is the time when most of the
major groups of animals first appear in the fossil record. This event is sometimes called the "Cambrian
Explosion", because of the relatively short time over which this diversity of forms appears. It was once thought
that the Cambrian rocks contained the first and oldest fossil animals, but these are now to be found in the earlier
Vendian strata.
Geologic Time Activity Rubric
1
2
3
4
5
6
7
8
Inquiry Skills
Procedure A: The Time Line shows both Geological Eons and Era
Procedure B: The Time Line shows the breakdown of the
Phanerozoic Eon into its Eras and Periods
The thickness of each time division has been calculated correctly
and is measured properly on the time line.
Overall Inquiry Skills Mark
Communication Skills
The time line is effectively labeled and coloured. The overall
presentation value of the timeline is very effective.
Procedure A: A concise description of each time division is
included. This description highlights the important geological,
biological and atmospheric events of each time division.
Procedure B: A concise description of each time division is
included. This description highlights the important geological,
biological and atmospheric events of each time division.
Effective communication skills are used (scientific language, clear
grammar and diction, proper spelling and punctuation)
The student summarizes events in his/her own language.
Overall Communication Skills Mark
I or R
level 1
I or R
level 1
level 2
level 3
level 4
level 3
level 4
level 3
level 4
level 3
level 4
level
level 2
level
Geologic Time Activity Rubric
1
2
3
4
5
6
7
8
Inquiry Skills
Procedure A: The Time Line shows both Geological Eons and Era
Procedure B: The Time Line shows the breakdown of the
Phanerozoic Eon into its Eras and Periods
The thickness of each time division has been calculated correctly
and is measured properly on the time line.
Overall Inquiry Skills Mark
Communication Skills
The time line is effectively labeled and coloured. The overall
presentation value of the timeline is very effective.
Procedure A: A concise description of each time division is
included. This description highlights the important geological,
biological and atmospheric events of each time division.
Procedure B: A concise description of each time division is
included. This description highlights the important geological,
biological and atmospheric events of each time division.
Effective communication skills are used (scientific language, clear
grammar and diction, proper spelling and punctuation)
The student summarizes events in his/her own language.
Overall Communication Skills Mark
I or R
level 1
I or R
level 1
level 2
level
level 2
level