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In the early 1960s, the emergence of the theory of plate tectonics
started a revolution in the earth sciences. Since then, scientists have
verified and refined this theory, and now have a much better
understanding of how our planet has been shaped by plate-tectonic
processes. We now know that, directly or indirectly, plate tectonics
influences nearly all geologic processes, past and present. Indeed, the
notion that the entire Earth’s surface is continually shifting has
profoundly changed the way we view our world. People benefit from, and
are at the mercy of, the forces and consequences of plate tectonics.
With little or no warning, an earthquake or volcanic eruption can
unleash bursts of energy far more powerful than anything we can
generate. While we have no control over plate-tectonic processes, we now
have the knowledge to learn from them. The more we know about plate
tectonics, the better we can appreciate the grandeur and beauty of the
land upon which we live, as well as the occasional violent displays of
the Earth’s awesome power. This booklet gives a brief introduction to
the concept of plate tectonics and complements the visual and written
information in This Dynamic Planet (see Further reading), a map
published in 1994 by the U.S. Geological Survey (USGS) and the
Smithsonian Institution. The booklet highlights some of the people and
discoveries that advanced the development of the theory and traces its
progress since its proposal. Although the general idea of plate
tectonics is now widely accepted, many aspects still continue to
confound and challenge scientists. The earth-science revolution launched
by the theory of plate tectonics is not finished.
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