Transcript Rachel Seesan

Geology of Hawaii
By: Katie Donovan
Rachel Seesan
SCI 210 4/5/04
Dr. Sandy
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Hawaii has an area of 6,435 square miles
and the shoreline are 1,022 miles long
There are actually 132 islands in the Hawaii
Island Chain
The big island has five above the ocean
volcanoes which are oldest to the northwest
and youngest to southeast.
82 volcanoes in the Hawaii chain
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Mauna Kea is the tallest mountain in Hawaii
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at 13,796 feet
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8,800 different species of animals… most of
which are endangered
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1,193,001 live in Hawaii.. Less then 1% are
pure Hawaiian
• Hawaii was formed when a
molten 'hot spot' weakened
the Earth’s crust until it broke
open and molten lava started
pumping out.
• That one 'hot spot' stays in the
same place as the Pacific
Tectonic Plate moves slowly
northeast towards Japan and
has created all of the Hawaiian
Islands
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A volcano is defined as a
place where magma/or gas
from within the earth surface
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Explosions depend on two
characteristics:
1. The amount of gas in
proportion to liquid rock
2. The viscosity (stickiness)
of the liquid lava
“Hawaiian type” eruptions are
unique compared to other
types
• Rocks ejected from volcanic eruptions are known
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as volcanic ejecta
Hawaiian ejecta is known as pyroclastic (“firebroken”) rocks
Ejecta classified according to size.
Rocks found in Hawaii are also found in other
central Pacific islands
Hawaiian rocks differ in the process
• Most abundant mineral is feldspar
– White/gray with glassy or pearly
luster
– Cleavage seen on broken
surface
– Made of anorthite and albite
chemicals
Most abundant limestone is Calcite
– Rhombohedral cleavage
Quartz is the rarest mineral
– Glassy appearance and little/no
cleavage
• Serves multiple
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purposes to the
Hawaiian islands
Least known part of
the earth’s surface
• The shoreline is
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gradually cut back by
the horizontal direct
attack of the waves
Rock debris is
produced by this
process
• Series of elastic waves
• One of the most feared natural disasters
of Hawaii
• Caused by sudden displacement of rock in
the ocean
• Waves spread out and cause tidal waves
• Pele the goddess and creator of the Hawaiian
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Islands can create/destroy with fire
Bad luck to steal a piece of rock from the
Island… Pele will find revenge on you!
Includes sand, rocks, and lava rocks, and shells
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http://www.volcanogallery.com/lavarock.htm
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