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Free Desktop Pictures Biography
Niagara Falls
Niagara Falls is the collective name for three waterfalls that straddle the international border between the Canadian province of Ontario and the U.S. state of New York. They form the southern end of the Niagara Gorge.
From largest to smallest, the three waterfalls are the Horseshoe Falls, the American Falls and the Bridal Veil Falls. The Horseshoe Falls lie on the Canadian side and the American Falls on the American side, separated by Goat Island. The smaller Bridal Veil Falls are also located on the American side, separated from the other waterfalls by Luna Island. The international boundary line was originally drawn through Horseshoe Falls in 1819, but the boundary has long been in dispute due to natural erosion and construction.
Located on the Niagara River which drains Lake Erie into Lake Ontario, the combined falls form the highest flow rate of any waterfall in the world, with a vertical drop of more than 165 feet (50 m). Horseshoe Falls is the most powerful waterfall in North America, as measured by vertical height and also by flow rate.[3] The falls are located 17 miles (27 km) north-northwest of Buffalo, New York and 75 miles (121 km) south-southeast of Toronto, between the twin cities of Niagara Falls, Ontario, and Niagara Falls, New York.
Niagara Falls were formed when glaciers receded at the end of the Wisconsin glaciation (the last ice age), and water from the newly formed Great Lakes carved a path through the Niagara Escarpment en route to the Atlantic Ocean. While not exceptionally high, the Niagara Falls are very wide. More than 6 million cubic feet (168,000 m3) of water falls over the crest line every minute in high flow,[4] and almost 4 million cubic feet (110,000 m3) on average.
The Niagara Falls are renowned both for their beauty and as a valuable source of hydroelectric power. Managing the balance between recreational, commercial, and industrial uses has been a challenge for the stewards of the falls since the 19th century.
American Falls (large waterfall on the left) and Bridal Veil Falls (smaller waterfall on the right)
Canadian Horseshoe falls as viewed from Skylon Tower.
The Horseshoe Falls drop about 173 feet (53 m), while the height of the American Falls varies between 70–100 feet (21–30 m) because of the presence of giant boulders at its base. The larger Horseshoe Falls are about 2,600 feet (790 m) wide, while the American Falls are 1,060 feet (320 m) wide. The distance between the American extremity of the Niagara Falls and the Canadian extremity is 3,409 feet (1,039 m).
The volume of water approaching the falls during peak flow season may sometimes be as much as 202,000 cubic feet (5,700 m3, 5.7 million liters) per second.[5] Since the flow is a direct function of the Lake Erie water elevation, it typically peaks in late spring or early summer. During the summer months, 100,000 cubic feet (2,800 m3) per second of water actually traverses the falls, some 90% of which goes over the Horseshoe Falls, while the balance is diverted to hydroelectric facilities. This is accomplished by employing a weir with movable gates upstream from the Horseshoe Falls. The falls flow is further halved at night, and during the low tourist season in the winter, remains a flat 50,000 cubic feet (1,400 m3) per second. Water diversion is regulated by the 1950 Niagara Treaty and is administered by the International Niagara Board of Control
The features that became Niagara Falls were created by the Wisconsin glaciation about 10,000 years ago. The same forces also created the North American Great Lakes and the Niagara River. All were dug by a continental ice sheet that drove through the area, deepening some river channels to form lakes, and damming others with debris. Scientists argue that there is an old valley, buried by glacial drift, at the approximate location of the present Welland Canal.Aerial view of Niagara Falls, showing parts of Canada (left) and the United States (upper right).
When the ice melted, the upper Great Lakes emptied into the Niagara river, which followed the rearranged topography across the Niagara Escarpment. In time, the river cut a gorge through the north facing cliff, or cuesta. Because of the interactions of three major rock formations, the rocky bed did not erode evenly. The top rock formation was composed of erosion-resistant limestone and Lockport dolostone. That hard layer of stone eroded more slowly than the underlying materials. The aerial photo on the right clearly shows the hard caprock, the Lockport Formation (Middle Silurian), which underlies the rapids above the falls, and approximately the upper third of the high gorge wall.
Immediately below the hard-rock formation, comprising about two thirds of the cliff, lay the weaker, softer, sloping Rochester Formation (Lower Silurian). This formation was composed mainly of shale, though it has some thin limestone layers. It also contains ancient fossils. In time, the river eroded the soft layer that supported the hard layers, undercutting the hard caprock, which gave way in great chunks. This process repeated countless times, eventually carving out the falls.
"Niagara Falls. This name is Mohawk. It means, according to Mrs. Kerr, the neck; the term being first applied to the portage or neck of land, between lakes Erie and Ontario. By referring to Mr. Elliott's vocabulary, (chapter xi) it will be seen that the human neck, that is, according to the concrete vocabulary, his neck, is onyara. Red Jacket pronounced the word Niagara to me, in the spring of 1820, as if written O-ne-au-ga-rah."
Free Desktop Pictures Biography
Niagara Falls
Niagara Falls is the collective name for three waterfalls that straddle the international border between the Canadian province of Ontario and the U.S. state of New York. They form the southern end of the Niagara Gorge.
From largest to smallest, the three waterfalls are the Horseshoe Falls, the American Falls and the Bridal Veil Falls. The Horseshoe Falls lie on the Canadian side and the American Falls on the American side, separated by Goat Island. The smaller Bridal Veil Falls are also located on the American side, separated from the other waterfalls by Luna Island. The international boundary line was originally drawn through Horseshoe Falls in 1819, but the boundary has long been in dispute due to natural erosion and construction.
Located on the Niagara River which drains Lake Erie into Lake Ontario, the combined falls form the highest flow rate of any waterfall in the world, with a vertical drop of more than 165 feet (50 m). Horseshoe Falls is the most powerful waterfall in North America, as measured by vertical height and also by flow rate.[3] The falls are located 17 miles (27 km) north-northwest of Buffalo, New York and 75 miles (121 km) south-southeast of Toronto, between the twin cities of Niagara Falls, Ontario, and Niagara Falls, New York.
Niagara Falls were formed when glaciers receded at the end of the Wisconsin glaciation (the last ice age), and water from the newly formed Great Lakes carved a path through the Niagara Escarpment en route to the Atlantic Ocean. While not exceptionally high, the Niagara Falls are very wide. More than 6 million cubic feet (168,000 m3) of water falls over the crest line every minute in high flow,[4] and almost 4 million cubic feet (110,000 m3) on average.
The Niagara Falls are renowned both for their beauty and as a valuable source of hydroelectric power. Managing the balance between recreational, commercial, and industrial uses has been a challenge for the stewards of the falls since the 19th century.
American Falls (large waterfall on the left) and Bridal Veil Falls (smaller waterfall on the right)
Canadian Horseshoe falls as viewed from Skylon Tower.
The Horseshoe Falls drop about 173 feet (53 m), while the height of the American Falls varies between 70–100 feet (21–30 m) because of the presence of giant boulders at its base. The larger Horseshoe Falls are about 2,600 feet (790 m) wide, while the American Falls are 1,060 feet (320 m) wide. The distance between the American extremity of the Niagara Falls and the Canadian extremity is 3,409 feet (1,039 m).
The volume of water approaching the falls during peak flow season may sometimes be as much as 202,000 cubic feet (5,700 m3, 5.7 million liters) per second.[5] Since the flow is a direct function of the Lake Erie water elevation, it typically peaks in late spring or early summer. During the summer months, 100,000 cubic feet (2,800 m3) per second of water actually traverses the falls, some 90% of which goes over the Horseshoe Falls, while the balance is diverted to hydroelectric facilities. This is accomplished by employing a weir with movable gates upstream from the Horseshoe Falls. The falls flow is further halved at night, and during the low tourist season in the winter, remains a flat 50,000 cubic feet (1,400 m3) per second. Water diversion is regulated by the 1950 Niagara Treaty and is administered by the International Niagara Board of Control
The features that became Niagara Falls were created by the Wisconsin glaciation about 10,000 years ago. The same forces also created the North American Great Lakes and the Niagara River. All were dug by a continental ice sheet that drove through the area, deepening some river channels to form lakes, and damming others with debris. Scientists argue that there is an old valley, buried by glacial drift, at the approximate location of the present Welland Canal.Aerial view of Niagara Falls, showing parts of Canada (left) and the United States (upper right).
When the ice melted, the upper Great Lakes emptied into the Niagara river, which followed the rearranged topography across the Niagara Escarpment. In time, the river cut a gorge through the north facing cliff, or cuesta. Because of the interactions of three major rock formations, the rocky bed did not erode evenly. The top rock formation was composed of erosion-resistant limestone and Lockport dolostone. That hard layer of stone eroded more slowly than the underlying materials. The aerial photo on the right clearly shows the hard caprock, the Lockport Formation (Middle Silurian), which underlies the rapids above the falls, and approximately the upper third of the high gorge wall.
Immediately below the hard-rock formation, comprising about two thirds of the cliff, lay the weaker, softer, sloping Rochester Formation (Lower Silurian). This formation was composed mainly of shale, though it has some thin limestone layers. It also contains ancient fossils. In time, the river eroded the soft layer that supported the hard layers, undercutting the hard caprock, which gave way in great chunks. This process repeated countless times, eventually carving out the falls.
"Niagara Falls. This name is Mohawk. It means, according to Mrs. Kerr, the neck; the term being first applied to the portage or neck of land, between lakes Erie and Ontario. By referring to Mr. Elliott's vocabulary, (chapter xi) it will be seen that the human neck, that is, according to the concrete vocabulary, his neck, is onyara. Red Jacket pronounced the word Niagara to me, in the spring of 1820, as if written O-ne-au-ga-rah."
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