P
LATE TECTONICS IS THE
FIRST THEORY TO PROVIDE
A COMPREHENSIVE VIEW
of the processes that produced
Earth’ s major surface features,
including the continents and ocean
basins. Within the framework of
this theory, geologists have found
explanations for the basic causes
and distribution of earthquakes,
volcanoes, and mountain belts.
Further, we are now better able to
explain the distribution of plants
and animals in the geologic past, as
well as the distribution of
economically significant mineral
deposits.
F O C U S O N C O N C E P T S
To assist you in learning
the important concepts in this
chapter, focus on the following
questions:
What evidence was used to
support the continental drift
hypothesis?
What was one of the main
objections to the continental
drift hypothesis?
What is the theory of plate
tectonics?
In what major way does the plate
tectonics theory depart from the
continental drift hypothesis?
What are the three types of plate
boundaries?
Where does new lithosphere
form?
How do mountain systems such
as the Himalayas form?
What type of plate motion
occurs along a transform fault
boundary?
What evidence is used to
support the plate tectonics
theory?
What are the major driving
forces for plate tectonics?
What models have been
proposed to explain the driving
mechanism for plate motion?
This hiker is walking across glacial debris in Pakistan’s
rugged and remote Karakoram Range, a part of the
Himalayas. (Photo by Bill Stevenson)