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 Charles
Francis Richter co-developed
a method for measuring earthquake
intensity that accurately reflected
earthquake strength. The Richter Scale,
which was published in 1935, used a
seismograph to record actual earth motion
during an earthquake. |
|
 Agate
forms when silica
in solution seeps into a cavity in lava
and hardens in successive layers.
Chemically it consists of silicon and
oxygen, SiO2. |
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 The Mohole
Project drilled a hole down
to the boundary between the earth's crust
and mantle. Doing so would, it was believed, provide a
concrete check on theories about the age,
origin, and composition of the earth. |
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 Pterosaurs
"flying
lizards," were flying reptiles that
lived during the age of dinosaurs. Some
were as small as sparrows, while others
were as large as an airplane. They had
large brains, long tails, short necks,
and long, narrow wings. |
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