What Did Pangaea Look like?
Summary
TLDRThis script explores the ancient supercontinent Pangaea, hypothesizing its geography around 100-90 million years ago. It discusses the formation of mountain ranges like the Central Pangaean Range and the impact of oceans on climate and ecology. The video also delves into the ancient ocean currents and their effects on rainfall, leading to a reconstruction of the land cover with forests, deserts, and savannas. The summary concludes with the acknowledgment of the limitations of the reconstruction and the need for further collaborative research.
Takeaways
- 🧩 Alfred Wegener noticed that the continents fit together like a puzzle, leading to his theory of continental drift.
- 📚 Wegener published 'The Origin of Continents and Oceans' in 1915, introducing the concept of a supercontinent he called 'Pangaea'.
- 🌐 Pangaea existed for about 160 million years, forming around 335 million years ago and breaking apart about 175 million years ago.
- 🏞 The script attempts to estimate the geography of Pangaea around 100 to 90 million years ago, during the Triassic-Jurassic extinction event.
- 🏞️ Major mountain ranges like the Himalayas had not yet formed during Pangaea's existence, with older ranges such as the Appalachians and Scottish Highlands being prominent.
- ⛰️ The central Pangaea mountain range was formed by the convergence of older mountain ranges across the supercontinent.
- 🌊 The Panthalassa Ocean surrounded most of Pangaea, with the Tethys Sea being a significant water body within it.
- 🌡️ Carbon dioxide levels were significantly higher 200 million years ago, resulting in a warmer global climate with no glaciers at the poles.
- 🌳 The environment of Pangaea was likely a mix of forests in wet areas and deserts in dry areas, with savannas as transitional zones.
- 🌍 Ocean currents and wind patterns would have influenced the climate and ecology of Pangaea, with warm currents fostering forests and cold currents creating deserts.
- 🗺️ The video script concludes with a hypothetical map of Pangaea's geography based on the discussed factors, acknowledging the need for further research and collaboration.
Q & A
What did Alfred Wegener notice about the continents in the early 20th century?
-Alfred Wegener noticed that the eastern coast of South America and the western coast of Africa fit together nicely, almost like two pieces of a puzzle, suggesting the concept of continental drift.
What did Wegener call the supercontinent in his 1915 book?
-Wegener called the supercontinent 'Urkontinent' in German in his 1915 book 'The Origin of the Continents and Oceans'.
What term did Wegener coin for the supercontinent in the 1920 edition of his book?
-In the 1920 edition of his book, Wegener coined the term 'Pangaea' from the Greek words 'pan' meaning all and 'Gaia' meaning earth.
What is the significance of the Central Pangaean Range in the context of Pangaea?
-The Central Pangaean Range refers to a single continuous mountain range that would have existed across the supercontinent Pangaea, formed by the Appalachian Mountains, the Little Atlas Mountains, and the Scottish Highlands.
How did the breakup of Pangaea contribute to the formation of today's major mountain ranges?
-The breakup of Pangaea led to the formation of many of today's major mountain ranges as the continents moved apart and collided, causing uplift and the creation of mountains like the Himalayas.
What was the Panthalassa Ocean and how did it relate to the world's climate during Pangaea's existence?
-The Panthalassa Ocean was the ocean that encompassed most of the world during Pangaea's existence. Its size and the ocean currents influenced the climate and ecology of the supercontinent, affecting rainfall and creating arid and humid regions.
How did the ocean currents during Pangaea's time potentially impact the climate?
-Ocean currents during Pangaea's time would have influenced the climate by affecting rainfall patterns. Warm water currents would have increased evaporation and rainfall near the coasts, while cold currents would have resulted in less evaporation and drier climates inland.
What was the Virgin Orogeny and its impact on the mountain ranges of Pangaea?
-The Virgin Orogeny was a substantial mountain-building event that led to the growth of the Alps, Pyrenees, Ural Mountains, and Tian Shan Mountains, placing mountains along significant lines on the map of Pangaea.
How did the high levels of carbon dioxide during Pangaea's time affect the global climate?
-The high levels of carbon dioxide, about 5 times greater than today's levels, resulted in global temperatures averaging roughly 3 degrees Celsius warmer than modern times, creating a greenhouse earth with subtropical and tropical climates even at the North Pole.
What were the primary determining factors for the environment in Pangaea based on the script?
-The primary determining factors for the environment in Pangaea were moisture levels, influenced by ocean currents and proximity to the sea, which resulted in forests in wet areas and deserts in dry areas, with savannas as transitional zones.
What method does the script suggest for improving the map of Pangaea's geography?
-The script suggests collecting and analyzing plant fossils from the Pangaea era to determine the type of environment they grew in, which could be used to reconstruct the landscape more accurately.
Outlines
🌏 Formation and Concept of Pangaea
The script begins with an exploration of Alfred Wegener's observation of continental fit and his subsequent publication of the theory of continental drift, culminating in the concept of 'Pangaea'. Pangaea, a supercontinent from 335 to 175 million years ago, underwent constant geological changes. The video aims to estimate the geography of Pangaea around 100 to 90 million years ago, focusing on its mountain ranges, such as the Central Pangaeic Range formed by the Appalachian Mountains, the Little Atlas Mountains, and the Scottish Highlands. These ancient ranges, along with others like the Laurentian Mountains and the Guiana Shield, shaped the supercontinent's landscape. The Andes and the mountains of eastern Brazil and western Africa were also discussed, highlighting the Virgin Orogeny's role in creating the Alps, Pyrenees, and other Eurasian ranges.
🌊 Ocean Currents and Climate of Pangaea
The second paragraph delves into the oceanography of Pangaea, focusing on the Panthalassa Ocean and the Tethys Sea. It discusses the influence of these bodies of water on climate and ecology, emphasizing the role of ocean currents in shaping weather patterns. The script speculates on the likely circulation patterns based on the Earth's rotation and wind patterns, suggesting the existence of gyres in the northern and southern hemispheres. The monsoon season's impact on rainfall is also considered. The paragraph highlights how higher CO2 levels during Pangaea's time, compared to today, would have resulted in a warmer 'greenhouse Earth', affecting the distribution of forests, deserts, and savannas based on moisture availability rather than temperature.
🏞️ Reconstructing Pangaea's Land Cover
The final paragraph discusses the reconstruction of Pangaea's land cover, using the understanding of ocean currents and ancient climate conditions. It describes how cold and warm ocean currents would have influenced the distribution of deserts and forests, respectively. The script proposes a hypothetical map of Pangaea with equatorial forests, extensive deserts in the interiors, and savannas as transition zones. It acknowledges the limitations of this reconstruction and suggests that a more accurate depiction would require extensive collaboration and analysis of plant fossils from the era. The video concludes by inviting viewers to support the creator's Patreon for more content and to provide feedback on the map created in the video.
Mindmap
Keywords
💡Alfred Wegener
💡Continental Drift
💡Pangaea
💡Plate Tectonics
💡Mountain Ranges
💡Geological Timescale
💡Ocean Currents
💡Panthalassa Ocean
💡Climate and Ecology
💡Carbon Dioxide Levels
💡Monsoon Season
Highlights
Alfred Wegener's observation of the fitting coastlines of South America and Africa led to the hypothesis of continental drift.
Wegener published 'The Origin of Continents and Oceans' in 1915, introducing the concept of a supercontinent.
The term 'Pangaea' was coined from Greek, meaning 'all earth', and popularized in the 1920 edition of Wegener's book.
Pangaea existed for approximately 160 million years, forming around 335 million years ago and breaking apart 175 million years ago.
The geological processes within Pangaea were dynamic, with the supercontinent constantly changing over time.
Major mountain ranges like the Himalayas had not yet formed during Pangaea's existence.
Older mountain ranges such as the Appalachians, Little Atlas, and Scottish Highlands formed a continuous range called the Central Pangaean Range.
The Central Pangaean Range was once as tall as the Himalayas but has since been eroded to its current form.
The Panthalassa Ocean, encompassing most of the world, influenced the climate and ecology of Pangaea.
Ocean currents and wind patterns during Pangaea's time can be inferred from the Earth's rotation and historical wind patterns.
The equatorial current and monsoon season would have played a significant role in the distribution of rainfall across Pangaea.
Carbon dioxide levels were significantly higher during Pangaea's time, leading to a warmer 'greenhouse earth'.
The climate of Pangaea was characterized by forests in wet areas and deserts in dry areas, with savannas as transitional zones.
The rainshadow effect would have created arid regions on the leeward side of mountain ranges.
The reconstruction of Pangaea's geography is an approximation based on current geological knowledge and fossil evidence.
Further research involving plant fossils could provide a more detailed understanding of Pangaea's landscape.
The video suggests using Patreon support for continued creation of educational content.
Transcripts
in the early 20th century the German
scientist Alfred Wegener noticed that
the eastern coast of South America and
the western coast of Africa fit together
nicely almost like two pieces of a
puzzle fitting together then Madagascar
fit nicely around the side of Africa
while parts of India seemed to have a
place as well despite heavy criticism
Wagner went on to publish the book the
origin of the continents and oceans in
1915 pushing the concept of what he
called her continent meaning
supercontinent in German except in a
1920 edition of the book where for a
single time he called the land of the
Pangaea of the Carboniferous coining the
term from the Greek pan meaning the
entire or all and Gaia meaning earth of
course it was the Latinization of this
word that became the more common phrase
now Pangaea and today Pangaea and the
larger theory of plate tectonics are
more or less common knowledge beyond
that though I don't know if I've ever
actually seen a good prediction on what
the continent actually looked like most
maps you'll find are either too
simplistic for my taste or just an
artistic representation of Pangaea which
can trade accuracy for aesthetic so what
I'd like to do today is make a rough
estimate of what some of the geography
of Pangaea was like and hopefully by the
end we'll have a cool map for something
obviously this will just be an
approximation based on what we know so
far about the supercontinent so with
that in mind let's get started the first
Pangaea itself existed for around 160
million years forming around 335 million
years ago and breaking apart roughly 175
million years ago over this time Earth's
geological engine was still turning
underneath meaning that on a geologic
timescale Pangaea would have been
constantly changing and so one general
map of Pangaea can't really be made
instead we're going to need to pick a
specific time in pangaea's past to look
at this one's gonna be a bit arbitrary
but we're going to aim for between 100
and 90 million years to 230 million
years ago this was around the time of
the triassic-jurassic extinction event
during which 20 to 30 percent of all
marine species went extinct for this
time the most accurate map for Pangaea I
could
and was this one but using this we can
now begin to look at specific features
and to start and look to look at some of
the mountain ranges that would and would
not have existed during this time for
starters nearly every major mountain
range on earth today had not formed yet
the Himalayas for example only began to
form 50 million years ago when India
collided with Asia and overall it was
the tearing apart of Pangaea that
actually gave us many of our mountains
and the reason these all happened to be
our tallest is because they haven't had
enough time to a road so to find out
what would have been around during this
time we need to look at some of the
oldest mountains remaining on the earth
such as the Appalachian Mountains of the
United States
the little Atlas Mountains of Morocco
and the Scottish Highlands of Great
Britain all of which are nearly 500
million years old
now it just so happens that these three
mountain ranges would have formed a
single continuous mountain range across
the supercontinent called the central
pangaean range and while none of these
ranges stand particularly high today
four different mountain building events
in the past produced a mountain range
that was once as tall as the Himalayas
are now essentially separating the
continent between the two remnants of
older supercontinent Gondwana and
Laurasia it was only with several
hundred million years of weathering and
erosion that these once great mountains
were whittled away to the gentle slopes
of today however there were of course
other mountain ranges here as well
nearby the Laurentian Mountains of
Quebec reaching into Greenland for
example were also created during the
Grenville orogeny
making this area of Pangaea occupied now
by Canada and the United States some of
the most mountainous land on the earth
at the time then there was the Guiana
Shield a series of mountains and
Highlands in South America with a
history that extends back nearly 1.7
million years though you can just barely
make it out on modern elevation maps of
the region we also would have seen some
of the earliest mountain building in the
Andes with the start of the Andean
orogeny these would have been just the
beginnings of mountains however and
nothing like what they are now
then as the lower section of Pangea what
was previously Gondwana began to tear
itself apart
splitting Africa from South America
mountains were created around the divide
resulting in the mountains of eastern
Brazil and western Africa South Africa
is actually where many of the world's
oldest mountain ranges are today with
the oldest being the Macondo mountains
lastly I want to talk about the Virgin
orogeny which was another substantial
mountain building event that led to the
growth of the Alps and the Pyrenees in
Europe and spread all the way out to the
Ural Mountains of Russia and the tian
shan mountains of central asia as well
as many other mountain ranges sprawling
all the way to the far coastal primordia
region also in modern-day Russia
this places mountains roughly along
these lines on our map of Pangaea and
with that we finished making the
important two mountain ranges at the
time after mountains next i'd actually
like to talk about the ocean first there
was the Panthalassa ocean the ocean
which encompassed most of the world with
its name literally translating into the
all sea in greek and then we'd get the
beginnings of the toughest if considered
separate from the Panthalassa ocean and
this body of water would have been
around a sixty million square kilometers
a bit smaller than the indian ocean
today but still much larger than the
Arctic Ocean what I'm interested in
however isn't the size of these oceans
but how the ocean during this time would
have influenced the climate and ecology
of bland I don't think anyone will be
surprised to hear that the ocean can
affect climate in multiple different
ways in terms of rainfall lands directly
beside the ocean will typically
experience greater amounts of it while
the continental interiors the lands
furthest from the ocean will become
increasingly arid we can see a similar
effect taking place across Central Asia
today where due to its remoteness a band
of dry regions can be found crossing
nearly the entire body of Asia but I
wish it were that simple the thing we
really need to look at is ocean currents
or how the waters of the ocean would
have circulated around the world that
during this time
now there isn't really great fossil
evidence for what ocean currents would
have been like so there's nothing really
tangible for us to go on but we still
know how the earth was rotating
basically the same way it does now and
because of this we know that the wind
patterns across the earth would be
virtually the same as they are now
meaning they'd look like this now it's
the winds that push surface waters
around so knowing these winds we can
reconstruct a general schematic for
water circulation at least at the
surface first by the equator both winds
from north and south pushed the water in
a westerly direction creating an ocean
current moving to the west across
equatorial waters because it's at the
equator these waters will also be warm
water currents which will be important
later this equatorial current would
continue flowing westward from the
Panthalassa
ocean pushing warm water into the
tempest until it reached land where this
happened the waters would have been
diverted around in the northern
hemisphere this sends water upwards and
eventually back out cooling down in the
process in the south well a similar
thing happens as the water deflects and
cools down a little before getting sent
back east tracing these water movements
onto the other side of the continent
we'd still have that westward moving
current at the equator due to the trade
winds in the north this current would
have mostly deflected downward with some
of its drying into this northern inland
ocean area the downward flowing waters
would begin warming back up eventually
joining the equatorial current
completing the northern ocean gyre
in the south the current would have to
travel a bit further until it came into
contact with this shoulder of land here
the waters were diverted as well with
some of them traveling back up north
again warming in the process and then
some of the water would also divert to
the south and travel as cold water
across the southern end of Pangaea until
joining with the currents here and
keeping on eastward completing the
Southern Ocean gyre and there you have
it a basic illustration of what the
ocean currents that interacted with the
lands could have looked like lastly and
I'm not going to really explain why
there would have been a yearly
equatorial monsoon season blowing great
amounts of rain from the Panthalassa
into the tempest inundating many of the
lands surrounding the tethers on with
great amounts of
honor knowing these simple
characteristics about the earth and it's
ocean at this time we're almost ready to
start figuring out the land cover but
before we do that we need to know how
different the conditions of the earth
would have been compared to what they
are now firstly 200 million years ago
average carbon dioxide levels would have
been around 1850 parts per million in
the atmosphere compared to 400 parts per
million were hovering at today meaning
the co2 concentrations around this time
would have been about 5 times greater
than what it is today and six times
greater than what it was before the
Industrial Revolution this would have
resulted in global temperatures
averaging roughly 3 degrees Celsius
warmer than modern times in while this
might not sound like a lot fossils from
the North Pole 200 million years ago
show subtropical and even some tropical
plants growing here and there's
absolutely no evidence of glaciers or
really any ice existing on earth at this
time besides maybe within the mountain
ranges in other words this would have
been a greenhouse earth where even the
North Pole could have been covered in
tropical rainforests if the moisture
levels were right because only warm
climate environments could have existed
at this time this rules out the
existence of any large temperate
environments so if temperature was less
of a designing factor at the time this
would have made moisture the primary
determining factor for the environment
because of this the lands of Pangaea
would have been balanced between
basically two radically different
environments where it was wet there
would have been forests and where it was
dry there would have been hot deserts
and of course where it rained a moderate
amount a narrow tropical savanna would
have appeared as a transition zone
between the two extremes using the ocean
currents and mountains then we can start
to figure out where there might have
been forests and desert and then fill in
the lands between them with savanna to
start I'm first going to look at the
ocean currents cold water evaporates
very little producing very low levels of
moisture in the atmosphere which in turn
produces only small amounts of rain so
beside lands with cold currents running
along them I'm going to put deserts in
where the surface waters are warm
evaporation occurs more readily filling
the air with moisture which eventually
falls back to the surrounding earth as
rain
so wherever warm waters flow beside the
land I'm going to make into forests
these trends still clearly exist to this
day by the way like off the coast of
California where cold ocean water moves
turning the land here pretty arid and
creating environments like the Mojave
Desert while on the other side of the
u.s. warm Atlantic waters flow up from
the Caribbean resulting in a much more
humid eastern United States this is also
true for South America Africa and
Australia however I mentioned earlier
that the further into the interior you
go the likely the drier it would become
so I'm also going to push the deserts
further into the interiors where they
already exist on the opposite end of
this as I mentioned before as well a
seasonal monsoon would have come into
these lands sending moisture further
inland likely pushing the forests at the
equator deeper into the continent the
forests would likely extend all the way
to the central pangaean mountains but no
further making one side of the mountain
range extremely wet and rainy while the
other side dry and desert again we see
this today in places like India where
moisture is brought all the way up until
the Himalayas and the lands on the other
side like Tibet are extremely arid this
is called the rainshadow effect so the
equatorial forest would likely not have
crossed over the central pyncheon
mountains this also would have prevented
forests from moving too far into western
Pangaea lastly I'm going to place narrow
savanna regions around the edges of the
land as the ocean usually acts as the
moderating force for temperature and
humidity so in the end we get a map that
looks like this
and using this I can use satellite maps
to add a little texture and that's about
as good of a map as I can create without
any more information and the only better
method I can come up with is to collect
all the plant fossils dating back to
around this time determine what type of
environment these plants would have
grown in and used them to reconstruct
the landscape of Pangaea but something
like that is a job for more than just
one person and would actually require
pretty substantial collaboration so
that's where I'm going to need to stop I
hope you enjoyed this video and if you'd
like to keep seeing more like
this I suggest checking out my patreon I
don't do sponsorships on this channel so
it really helps to get a reliable source
of income and lets me plan things
further into the future plus you can get
your name up here at the end of my
videos like all these people if not well
maybe then just subscribe and let me
know if you have any ideas on how to
improve the map I made in this video
maybe if there's enough additional
things to look at I could make a follow
up other than that
thanks for watching
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