Difference between revisions of "AY Honors/Waterfalls/Answer Key"

Revision as of 21:57, 4 September 2006

Waterfalls redirects here. For the Paul McCartney single, see Waterfalls (Paul McCartney song).

Hopetoun Falls near Otway National Park, Victoria, Australia

A waterfall is usually a geological formation resulting from water, often in the form of a stream, flowing over an erosion-resistant rock formation that forms a sudden break in elevation. Waterfalls may also be artificial, and they are sometimes created as garden and landscape ornament.

Some waterfalls form in mountain environments where erosion is rapid and stream courses may be subject to sudden and catastrophic change. In such cases, the waterfall may not be the end product of many years of water action over a region, but rather the result of relatively sudden geological processes such as thrust faults or volcanic action.

The hobby of falls bagging is blossoming in many parts of the world.

Formation

Formation of a waterfall

Typically, a stream flow across an area of formations strata will form shelves across the streamway, elevated above the further stream bed when the less erosion-resistant rock around it disappears. Over a period of years, the edges of this shelf will gradually break away and the waterfall will steadily retreat upstream, creating a gorge of recession. Often, the rock strata just below the more resistant shelf will be of a softer type, meaning undercutting will occur here to form a shallow cave-like formation known as a rock shelter (also known as a rock house) under and behind the waterfall. Eventually, the outcropping, more resistant cap rock will collapse under pressure to add blocks of rock to the base of the waterfall. These blocks of rock are then broken down into smaller boulders by attrition as they collide with each other, and they also erode the base of the waterfall by abrasion, creating a deep plunge pool.

Waterfalls can also form due to glaciation, whereby a stream or river flowing into a glacier continues to flow into a valley after the glacier has receded or melted. The large waterfalls in Yosemite Valley are examples of this phenomenon.

Streams often become wider and more shallow just above waterfalls due to flowing over the rock shelf, and there is usually a deep pool just below the waterfall due to the kinetic energy of the water hitting the bottom.

Havasu Falls, near Supai, Arizona, is an example of a plunge waterfall.

Examples of large waterfalls

Template:Main

Angel Falls, the world's highest at 979 m (3212 ft), in Venezuela
Tugela Falls, the world's second highest at 947 m (3110 ft), in KwaZulu-Natal province, Republic of South Africa.
Ramnefjellsfossen, the world's third highest at 808m (2685 ft), at Stryn, Nesdalen, Norway.
Victoria Falls, the world's widest, on the Zambezi River, on the border between Zambia and Zimbabwe
Boyoma Falls, with the world's highest volume, 17,000 m³/s (600,000 ft³/s), on the Congo River, Democratic Republic of the Congo
Gocta, the fifth highest in the world at 771 m (2533 ft), located in the province Chachapoyas, Peru
Yosemite Falls, arguably the tallest in North America, located in Yosemite National Park, United States
Niagara Falls, most voluminous in North America, on the border between the United States and Canada
Rhine Falls, Europe's largest, located in Switzerland
Iguazu Falls, a tall and extremely wide fall located in South America on the Argentina/Brazil border
Jog Falls, India's highest and second highest in Asia, located in Karnataka state, India
Jurong Falls in Singapore is said to be the tallest man-made waterfall in the world
Broadgate Centre Falls in London second largest man-made falls after the Jurong Falls. Local workers use it to cool their feet of a lunch hour.

Gallery

Base of Tower Fall with rainbow-750px.JPG

Tower Fall in Yellowstone National Park, USA
Godafoss in Iceland
Angel Falls, Venezuela
Iguazu Falls, between Brazil and Argentina
Wailua Falls in Hawaii, USA
Staubbach Falls flows into the town of Lauterbrunnen, Switzerland
Dettifoss in Iceland
Man-made waterfall at the Australian National Botanic Gardens in Canberra, Australia
Waterfall near Brienzersee, Switzerland
Earthen Dam Waterfall in Waverly, New York, USA
Kaieteur.jpg

Kaieteur Falls in Guyana
Niagara Falls, on the border between Canada and the USA
A small part of the Krimml Falls, Austria. Scale is given by the people on the right
Burney Falls, located near Burney, California, USA
Victoria Falls in Africa.

External links

Template:Commons

ca:Cascada cs:Vodopád da:Vandfald de:Wasserfall et:Juga es:Cascada eo:Akvofalo eu:Ur-jauzi fr:Chute d'eau gl:Fervenza gu:ધોધ id:Air terjun it:Cascata he:מפל מים la:Cataracta lt:Krioklys nl:Waterval ja:滝 no:Foss nn:Foss pl:Wodospad pt:Cachoeira ru:Водопад simple:Waterfall sl:Slap su:Curug fi:Vesiputous sv:Vattenfall vi:Thác tr:Şelâle uk:Водоспад zh:瀑布

@@ Line 5: / Line 5: @@
 A '''waterfall''' is usually a [[geology|geological]] [[geologic formation|formation]] resulting from water, often in the form of a [[stream]], flowing over an [[erosion]]-resistant rock formation that forms a sudden break in elevation. Waterfalls may also be artificial, and they are sometimes created as [[garden]] and [[landscape]] ornament.
-Some waterfalls form in homosexual environments where native americans run around they are rapid and stream courses may be subject to sudden and catastrophic change. In such cases, the waterfall may not be the end product of many years of water action over a region, but rather the result of relatively sudden geological processes such as [[thrust fault]]s or [[volcano|volcanic action]].
+Some waterfalls form in [[mountain]] environments where [[erosion]] is rapid and stream courses may be subject to sudden and catastrophic change. In such cases, the waterfall may not be the end product of many years of water action over a region, but rather the result of relatively sudden geological processes such as [[thrust fault]]s or [[volcano|volcanic action]].
 The hobby of [[falls bagging]] is blossoming in many parts of the world.
@@ Line 19: / Line 19: @@
 [[Image:Havasu_Falls_1a_md.jpg|thumb|260px|left|[[Havasu Falls]], near Supai, Arizona, is an example of a plunge waterfall.]]
-==Types of waterfalls==
-; Block : Water descends from a relatively wide stream or river.
-; Cascade : Water descends a series of rock steps.
-; Cataract : A large waterfall. See [[Cataracts of the Nile]] for a well-known sequence of six.
-; Fan : Water spreads horizontally as it descends while remaining in contact with [[bedrock]].
-; Horsetail : Descending water maintains some contact with bedrock.
-; Plunge : Water descends vertically, losing contact with the bedrock surface.
-; Punchbowl : Water descends in a constricted form, then spreads out in a wider pool.
-; Segmented : Distinctly separate flows of water form as it descends.
-; Tiered : Water drops in a series of distinct steps or falls.
-; Multi step : A series of waterfalls one after another of roughly the same size each with its own sunken plunge pool.
 ==Examples of large waterfalls==
@@ Line 40: / Line 30: @@
 * [[Boyoma Falls]], with the world's highest volume, 17,000 m&sup3;/s (600,000 ft&sup3;/s), on the [[Congo River]], [[Democratic Republic of the Congo]]
 * [[Gocta]], the fifth highest in the world at 771 m (2533 ft), located in the province [[Chachapoyas Province|Chachapoyas]], [[Peru]]
-* [[Yosemite Falls]], the tallest in [[North America]], located in [[Yosemite National Park]], [[United States]]
+* [[Yosemite Falls]], arguably the tallest in [[North America]], located in [[Yosemite National Park]], [[United States]]
 * [[Niagara Falls]], most voluminous in North America, on the border between the United States and [[Canada]]
 * [[Rhine Falls]], Europe's largest, located in [[Switzerland]]