PHYSICAL GEOLOGY AND THE ENVIRONMENT
(2ND CANADIAN EDITION)
Chapter 1: Introduction to Physical Geology and the Environment
Chapter Summary:
Geology is the scientific study of the Earth. Early geologists used their knowledge of rocks and
minerals to find and exploit resources required by newly industrialized nations. Today,
geoscientists are involved in a wide range of activities including resource exploration,
environmental geology, geomatics, and engineering geology, and knowledge of geological
processes is required by individuals working in both wilderness and urban settings.
One of the most important theories in geology today is that of plate tectonics, which proposes
that the surface of the Earth is broken into plates that move relative to each other and allow
continents to move over time. Most geological features and processes operating on the Earth can
be related to plate tectonics.
The Earth is estimated to be at least 4.5 billion years old and is thought to have formed at the
same time as other planets in our solar system. During formation of the Earth, intense heat
caused it to melt and allowed the most dense materials to settle toward the centre of the planet,
forming a core. The lightest materials "floated" to the surface to form a crust. This process of
differentiation created the zoned internal structure of the Earth consisting of a dense core, thick
mantle, and relatively thin crust.
The earliest life forms on Earth were microorganisms (similar to modern cyanobacteria) that
formed mound-like structures called stromatolites. More complex life forms emerged after 600
million years ago, and by 100 million years ago dinosaurs wandered across our continental
interiors.
Erosion and transport of rocks exposed on the continents creates sediments that may form
sedimentary rocks over time. If these are deeply buried and heated they may change into
metamorphic rocks or may melt completely and form magma. Solidification of magma, either
underground or on the Earth's surface, produces igneous rocks. The "recycling" of Earth
materials as different rock types is conceptualized as the "rock cycle," and illustrates some of the
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PHYSICAL GEOLOGY AND THE ENVIRONMENT
(2ND CANADIAN EDITION)
many interactive processes operating within the Earth system.
Questions:
1. Which of the following are part of the Earth system. (Page 16-17)
A. Biosphere
B. Geosphere
C. Atmosphere
D. All of these and the hydrosphere
2. In which scenario below would you be likely to hire a geoscientist to help better understand
the situation? (Page 5-11)
A. A small community is worried about contamination of their water wells from an
industrial waste site.
B. A subway tunnel is being bored under a major city.
C. Finding the best route for a subsea pipeline.
D. Geoscientists might be employed in all of these scenarios!
3. In which of the following is geological knowledge useful? (Page 5-8)
A. Avoiding geologic and other natural hazards.
B. Supplying things we need.
C. Protecting the environment.
D. All of these are areas where geological knowledge is useful!
4. Continental drift was suggested by this person to explain the movement of the continents.
(Page 2-4)
A. William Logan
B. Alfred Wegner
C. William Smith
D. Tuzo Wilson
5. Pangea is the name of: (Page 2-4)
A. A country in Europe
B. A supercontinent
C. An OK continent
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