Class Notes (1,100,000)
CA (630,000)
UTSC (30,000)
EESA06H3 (600)
Lecture 10

EESA06H3 Lecture Notes - Lecture 10: The Maritimes, Mount Rundle, Eurasia


Department
Environmental Science
Course Code
EESA06H3
Professor
Nick Eyles
Lecture
10

This preview shows pages 1-2. to view the full 8 pages of the document.
Lecture 10 Canadas Geologic Journey: The Last 4 Billion Years
Exams dominant theme Plate tectonics
1. Continents grow through time by obduction
2. North American continent shows 5 growth
stages:
a.Arctica (2.7 Ga gigaannum)
b. Columbia (1.8 Ga)
c.Rodina (1.0 Ga)
Part of human life
a + b + c = Canadian Shield (the craton
core of North America: BROWN AREA)
d. Pangea assembly (350 Ma): Maritime
Canada is added during
Appalachians Orogeny (Appalachian
Mountains: BLUE RIGHT AREA)
e.Pangea breakup (<200 Ma): British Columbia is added during
Cordilleran Orogeny (e.g. Rockies: from Alaska to Mexico on the left)
Zircons
Derive from igneous rocks released into water
Sedimentary rock metamorphosed into a gneiss
used for uranium, lead age dating 2.7 billion years old
very small
put into a mass spectrometer to look at how much lead is in the crystal
Oldest rock on the planet
Acasta gneiss (North West Territories)
4 billion years ld
Gneiss has been metamorphosed
Detrital Detritus
oDerived from something else
eroded
Continents Grow through Time
INSERT MAP
Oldest rocks in the centre
embedded in the interior of
Begins to get younger as the land
disperses
www.notesolution.com

Only pages 1-2 are available for preview. Some parts have been intentionally blurred.

Deconstructing North America
oProvince identify rocks that extend over very large areas (similar in
appearance)
Very sharp boundaries
Can walk from one to the
other
Separated by the orogen
oOrogen the rocks that result
from orogeny (activity)
Most common rock found
gneiss
Smaller rocks colliding
with others separated
by orogens green stone
belts (metamorphosed
ocean rocks) and gneiss
1. The original North American
Continent, Arctica, which started to
form about 2.5 billion years ago from
smaller continents and was completed by
about 1.9 billion years ago when old
Archean cratons (e.g. Slave, Nain
provinces) were welded together by the
Trans-Hudson Orogen and others.
oEarliest North American continent
oGreenland part of it broke off about 80 million years ago
oSeparated by a failed rift
2. Added to the North American continent during the formation of Nena about 1.8
billion years ago after the Penokean Orogeny.
3. Added during the formation of Rodinia about 1.3 billion years ago during the
Grenville Orogeny.
4. Added during the formation of Pangea about 600 million 300 million years ago.
5. Added after the breakup of Pangea about 250 million years ago.
oCordillera orogeny added after the breakup
Lithoprobe
Probing rocks
www.notesolution.com
You're Reading a Preview

Unlock to view full version

Only pages 1-2 are available for preview. Some parts have been intentionally blurred.

dancing elephants hydraulic
plate pushed down onto the
ground, subject to strong vibration
oProducing seismic waves
that go down to the ground
oRocks with different
hardness, density, types
oEnables us to see what is
under the ground about
70km down
Used to better understand the
Canadian Shield
Transects cross-sections through
the shield
The earth has cooled down
Labrador is added to Canada
How their rocks were added to the
north American continent
Wasnt all formed at the same time
Uniformitarianism present is the
key to that past
Ancient earth behaved as the
continent behaved as well
Canadian Shield pene plain
Almost a plain, flat
Forestry, lakes
Political unification of the provinces 1867-1949
An analog for welding of geological provinces through geologic time
Driving the golden spike November 1885
Obduction
Results in cratonization building of cratons and shields
Obduction has worked to build the provinces
www.notesolution.com
You're Reading a Preview

Unlock to view full version