Earthquakes

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Pangaea. At about 220 million years ago, Pangaea began to break up into sub-blocks. According
to the book Volcanoes, Earthquakes, and the Formation of Continents, these sub-blocks were
called "Gondwana (which corresponds approximately to the continents of the present southern
hemisphere) and Laurasia (the northern hemisphere)" (Kohler 15). According to Pierre Kohler,
"The earth's surface is divided into 13 plates: seven large ones (the largest corresponding to the
Pacific) and six small ones" (18-19). The book Earthquakes by Margaret Poynter states that a
person named Robert Mallet studied earthquakes. He made tests, drew a world map, and
recreated earthquakes only to find that rocks are being overstressed at the faults. "A fault is the
place where two plates meet and are rubbed against each other" (Groiler Electronic Publishing,
Inc.). The book, Predicting Earthquakes, the author points out "There are generally three kinds of
faults: normal, ...