continents and the magnetic poles move (Figure6.10).
Figure 6.10: The left side image shows the apparent north pole locations for two different
continents, Europe and North America, if the continents were always in their current loca-
tions. When continental drift is taken into account, the two paths merge into one since there
is only one magnetic north pole. ( 6 )
Lesson Summary
- In the early part of the 20thcentury, scientists began to put together evidence that the
continents could move around on Earth’s surface. - The evidence for continental drift included the fit of the continents; the distribution
of ancient fossils, rocks, and mountain ranges; and the locations of ancient climatic
zones. - Although the evidence was extremely strong, scientists could not think of a mechanism
that could drive solid continents to move around on the solid earth and most rejected
the idea. - ContinentaldriftwouldresurfaceafterWorldWarIIwhenamechanismwasdiscovered.
Review Questions
- Why can paper cutouts of the continents including the continental margins be pieced
together to form a single whole? - Howcanthelocationswhereancientfossilsarefoundbeusedasevidenceforcontinental
drift? - To show that mountain ranges on opposite sides of the Atlantic formed as two parts
of the same range and were once joined, what would you look for? - What are the three possible explanations for apparent polar wander when the rocks are
all on one continent? If the rocks are on more than one continent, which explanation