Each step in the development of the theory of continental drift is supported by evidence. Match each step with the appropriate
evidence below.
Continental drift is pushing Europe and North America apart, and Asia and the Indian subcontinent together. Although Alfred
Wegener identified the process of continental drift in 1912, he was unable to explain how it worked. Wegener suggested that perhaps
the rotation of the Earth caused the continents to shift towards and apart from each other. Over the last century, evidence has been
discovered that explains Wegener's original idea.
New crust is forming between two plates that are
moving apart. As the seafloor grows wider, the
continents on opposite sides of the ridges move
away from each other.
Suggest that the continents were once part of a
supercontinent as pollen from plants could not
travel great distances.
Although magnetite crystals point to the magnetic
north pole, the location of the pole seemed to
wander.
First piece of evidence suggesting that the two
continents had once been connected.
Suggest that the continents were once part of a
supercontinent, now broken pieces have similar
features.
Glossopteris Flora: Similarities in fossils, particularly in the five southern landmasses: South America, Africa, Antarctica,
India, and Australia.
Magnetic Polarity: Magnetite crystals in fresh volcanic rock point to the current magnetic north pole no matter what
continent or where on the continent the rocks are located. Older rocks that are of different ages do not point to the same
locations or to the current magnetic north pole.
Seafloor Spreading: Underwater exploration and the 1977 Tharp-Heezen map has revealed seafloor spreading.
Continental Structure Evidence: The locations of major structural features of the continents, including shields, stable
platforms, and folded mountain belts.
Continental Fit: The coasts of western Africa and eastern South America looked like the edges of interlocking pieces of a
jigsaw puzzle.