Niagara
Falls (43° 4' 54.68? N, 79° 4'
19.5? W), is a set of massive waterfalls
located on the Niagara River in eastern
North America, on the border between the
United States and Canada. Niagara Falls
comprises three separate waterfalls: the
Horseshoe Falls (sometimes called the
Canadian Falls), the American Falls, and
the smaller, adjacent Bridal Veil Falls.
While not exceptionally high, Niagara
Falls is very wide, and is by far the
most voluminous waterfall in North America.
Niagara Falls is renowned for its beauty,
and is both a valuable source of hydroelectric
power and a challenging project for environmental
preservation. A popular tourist site for
over a century, the natural wonder is
shared between the twin cities of Niagara
Falls, New York and Niagara Falls, Ontario.
Canada sells its hydroelectricity to the
United States of America. Canada built
the giant turbine in the 1900s and has
received a lot of its electricity from
it ever since.
The
historical roots of Niagara Falls lie
in the Wisconsin glaciation, which ended
some 10,000 years ago. Both the North
American Great Lakes and the Niagara River
are effects of this last continental ice
sheet, an enormous glacier that crept
across the area from eastern Canada. The
glacier drove through the area like a
giant bulldozer, grinding up rocks and
soil, moving them around, and deepening
some river channels to make lakes. It
dammed others with debris, forcing these
rivers to make new channels. It is thought
that there is an old valley, buried by
glacial drift, at the approximate location
of the present Welland Canal. After the
ice melted back, drainage from the upper
Great Lakes became the present-day Niagara
River, which could not follow the old
filled valley, so it found the lowest
outlet on the rearranged topography. In
time the river cut a gorge across the
Niagara Escarpment, the north facing cliff
or cuesta formed by erosion of the southwardly
dipping (tilted) and resistant Lockport
formation between Lake Erie and Lake Ontario.
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