The document describes the layers of the Earth from the crust on the outside to the inner core on the inside. It then discusses continental drift theory proposed by Alfred Wegener in 1912, which suggested that the continents were once joined together in a supercontinent called Pangaea approximately 200 million years ago and have been slowly drifting apart ever since at a rate of about 2.5 cm per year, forming the seven continents seen today. Wegener provided five pieces of evidence to support this idea: the matching shapes of continental coastlines, similar fossil records, matching rock types, corresponding mountain ranges, and glacial marks pointing in unexpected directions.

1. • Label the layers of the Earth
3
1
4
5
2
1. Upper
Mantle
2. Inner Core
3. Crust
4. Lower Mantle
5. Outer Core

2. ReviewReview
►Layers of the EarthLayers of the Earth
►CrustCrust
►MantleMantle
►Outer coreOuter core
►Inner coreInner core

3. Continental DriftContinental Drift
Alfred WegenerAlfred Wegener
proposed this idea aroundproposed this idea around
19121912
German scientistGerman scientist
Ideas were not acceptedIdeas were not accepted
at firstat first

4. Continental DriftContinental Drift
The continents are movingThe continents are moving
At one time, in the distant past,At one time, in the distant past,
all the continents wereall the continents were
connectedconnected
PangaeaPangaea
From the
Greek word
that means
“all Earth”
This is what
he said…

6. Continental DriftContinental Drift
About 200 million years ago (mya)About 200 million years ago (mya)
Pangaea began to break apartPangaea began to break apart
Moved about 2.5 cm/yrMoved about 2.5 cm/yr
Eventually becoming the 7Eventually becoming the 7
continents of todaycontinents of today
5 pieces of evidence:5 pieces of evidence:
This is what
he said…

7. 1. Continent Shape1. Continent Shape
The continents seem toThe continents seem to
fit together like a giantfit together like a giant
jigsaw puzzlejigsaw puzzle

9. 2. Fossil Evidence2. Fossil Evidence
Found similar animal and plantFound similar animal and plant
fossils on matching coastlinesfossils on matching coastlines
of different continentsof different continents

11. 3. Rock Evidence3. Rock Evidence
Found the same types of rocksFound the same types of rocks
and minerals on matchingand minerals on matching
coastlines of different continentscoastlines of different continents

13. 4. Mountain Evidence4. Mountain Evidence
Some mountain rangesSome mountain ranges
on different continentson different continents
seem to matchseem to match

16. 5. Glacier Marks5. Glacier Marks
►Some glacier marks seem toSome glacier marks seem to
be going in the “wrong”be going in the “wrong”
directiondirection
►Glaciers form in theGlaciers form in the
mountains and move downmountains and move down
hill towards the oceanhill towards the ocean