Man-Made Caves of Salt

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Man-Made Caves of Salt
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An enormous salt mine has been operating beneath
Detroit for more than a century.
Click here to see a drawing of an 1896 mine
operation.
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This bed of salt is hundreds of millions of years
old and contains trillions of tons of salt.

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Detroit began using rock salt on icy roads in
1940 and began selling salt to other cities for
the same use.
Click here to see some other uses for salt.
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The mine spreads over 1,400 acres under Detroit
and its suburbs.
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Electric trucks do much of the work.
Click here to see a conveyor
Click here to see a drill truck
Click here to see a shovel
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The Process of Salt Mining
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The miners use a room-and-pillar method to get
the salt.
The black blocks represent pillars of salt.
The blue grid represents the tunnels where the
salt is mined.
A room and pillar mine.
Photo courtesy Detroit Salt Company
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Fifty miles of road carry construction equipment,
trucks, and cars, which had to be taken apart to
fit down the shaft.
Photo courtesy Kansas Geological Survey
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If the mine goes out of business, it could be
used to store important items or become a museum.
The Historic Wieliczka salt mine near Krakow,
Poland, houses a fascinating museum.
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The End
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An 1896 Mining Operation
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Early uses for salt included storing meat and
fish and making ice cream.
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Giant chainsaw trucks cut grooves in the mine
wall and huge conveyors move the salt blocks .
Underground salt mine conveyor Photo courtesy of
Kansas Geological Survey
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Drill trucks bore holes in the wall for dynamite.
Salt mine drill and transport. Photo courtesy of
Kansas Geological Survey
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Shovel trucks scoop up rock salt, which then goes
into dump trucks.

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