Dylife Gorge | |
---|---|
Dylife Gorge, June 2008 | |
Location within Powys | |
OS grid reference | SH891027 |
Principal area | |
Ceremonial county | |
Country | Wales |
Sovereign state | United Kingdom |
Police | Dyfed-Powys |
Fire | Mid and West Wales |
Ambulance | Welsh |
UK Parliament | |
The Dylife Gorge, located near Dylife, Powys, Mid Wales, was carved by the action (and aftermath) of the last Ice age. It is headed by the Ffrwd Fawr Waterfall.
Before the last Ice age, the River Twymyn did not flow through the valley. When the valley was filled by a glacier, the ice ground out a U-shaped glaciated valley. When the glacier that filled the valley melted the Twymyn started to run down the wide channel left behind and the fast flowing river further eroded the valley, cutting the V-shaped gorge as seen today. [1]
The long-distance footpath Glyndŵr's Way (Welsh: Llwybr Glyndŵr) passes nearby.
A valley is an elongated low area often running between hills or mountains, which will typically contain a river or stream running from one end to the other. Most valleys are formed by erosion of the land surface by rivers or streams over a very long period. Some valleys are formed through erosion by glacial ice. These glaciers may remain present in valleys in high mountains or polar areas.
Landforms are categorized by characteristic physical attributes such as their creating process, shape, elevation, slope, orientation, rock exposure, and soil type.
Watkins Glen State Park is in the village of Watkins Glen, south of Seneca Lake in Schuyler County in New York's Finger Lakes region. The park's lower part is near the village, while the upper part is open woodland. It was opened to the public in 1863 and was privately run as a tourist resort until 1906, when it was purchased by New York State. Initially known as Watkins Glen State Reservation, the park was first managed by the American Scenic and Historic Preservation Society before being turned over to full state control in 1911. Since 1924, it has been managed by the Finger Lakes Region of the New York State Office of Parks, Recreation and Historic Preservation.
Lake Passaic was a prehistoric proglacial lake that existed in northern New Jersey in the United States at the end of the last ice age approximately 19,000–14,000 years ago. The lake was formed of waters released by the retreating Wisconsin Glacier, which had pushed large quantities of earth and rock ahead of its advance, blocking the previous natural drainage of the ancestral Passaic River through a gap in the central Watchung Mountains. The lake persisted for several thousand years as melting ice and eroding moraine dams slowly drained the former lake basin. The effect of the lake's creation permanently altered the course of the Passaic River, forcing it to take a circuitous route through the northern Watchung Mountains before spilling out into the lower piedmont.
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Kolka Glacier is a glacier in North Ossetia, Russia, near Mount Kazbek, known for its surging properties. The most recent and the most powerful surge took place on 20 September 2002, resulting in the death of ca. 140 people.
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The Geology of Yorkshire in northern England shows a very close relationship between the major topographical areas and the geological period in which their rocks were formed. The rocks of the Pennine chain of hills in the west are of Carboniferous origin whilst those of the central vale are Permo-Triassic. The North York Moors in the north-east of the county are Jurassic in age while the Yorkshire Wolds to the south east are Cretaceous chalk uplands. The plain of Holderness and the Humberhead levels both owe their present form to the Quaternary ice ages. The strata become gradually younger from west to east.
The Afon Twymyn is a river in Powys, Mid Wales.
Lake Condon was a temporary lake in the Pacific Northwest region of North America, formed periodically by the Missoula Floods from 15,000 to 13,000 BC.
Overdeepening is a characteristic of basins and valleys eroded by glaciers. An overdeepened valley profile is often eroded to depths which are hundreds of metres below the deepest continuous line along a valley or watercourse. This phenomenon is observed under modern day glaciers, in salt-water fjords and fresh-water lakes remaining after glaciers melt, as well as in tunnel valleys which are partially or totally filled with sediment. When the channel produced by a glacier is filled with debris, the subsurface geomorphic structure is found to be erosionally cut into bedrock and subsequently filled by sediments. These overdeepened cuts into bedrock structures can reach a depth of several hundred metres below the valley floor.
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