Keyhole Falls
Encyclopedia
Keyhole Falls is the unofficial name for the largest waterfall
along the Lillooet River
in British Columbia
, Canada
. The falls are 75 feet (22.9 m) high and are a punchbowl type of waterfall
.
It is called Keyhole Falls because it resembles a giant old-fashioned keyhole
.
from a Plinian eruption
at Mount Meager
about 2350 years ago. The thick breccia soon eroded from water activity, forming Keyhole Falls. There was a massive flood
when the water first broke through the breccia. The flood was big enough that small house-sized blocks of breccia were carried away during the flood.
Waterfall
A waterfall is a place where flowing water rapidly drops in elevation as it flows over a steep region or a cliff.-Formation:Waterfalls are commonly formed when a river is young. At these times the channel is often narrow and deep. When the river courses over resistant bedrock, erosion happens...
along the Lillooet River
Lillooet River
The Lillooet River is a major river of the southern Coast Mountains of British Columbia. It begins at Silt Lake, on the southern edge of the Lillooet Crown Icecap about 80 kilometres northwest of Pemberton and about 85 kilometres northwest of Whistler...
in British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. The falls are 75 feet (22.9 m) high and are a punchbowl type of waterfall
Waterfall
A waterfall is a place where flowing water rapidly drops in elevation as it flows over a steep region or a cliff.-Formation:Waterfalls are commonly formed when a river is young. At these times the channel is often narrow and deep. When the river courses over resistant bedrock, erosion happens...
.
It is called Keyhole Falls because it resembles a giant old-fashioned keyhole
Keyhole
A keyhole is where a key is inserted to open a lock. It is more properly known as a keyway.Keyhole has the following meanings:* Gravitational keyhole is a region of an orbit where a small gravitational input could cause a small body to collide with the large body it is orbiting.* Keyhole surgery is...
.
Formation
Keyhole Falls was formed when the Lillooet River was dammed with brecciaBreccia
Breccia is a rock composed of broken fragments of minerals or rock cemented together by a fine-grained matrix, that can be either similar to or different from the composition of the fragments....
from a Plinian eruption
Plinian eruption
Plinian eruptions, also known as 'Vesuvian eruptions', are volcanic eruptions marked by their similarity to the eruption of Mount Vesuvius in AD 79 ....
at Mount Meager
Mount Meager
Mount Meager, originally known as Meager Mountain, is a complex volcano in the Sea-to-Sky Corridor of southwestern British Columbia, Canada. It is located north of Vancouver at the northern end of the Pemberton Valley. Part of the Cascade Volcanic Arc of western North America, its summit is above...
about 2350 years ago. The thick breccia soon eroded from water activity, forming Keyhole Falls. There was a massive flood
Flood
A flood is an overflow of an expanse of water that submerges land. The EU Floods directive defines a flood as a temporary covering by water of land not normally covered by water...
when the water first broke through the breccia. The flood was big enough that small house-sized blocks of breccia were carried away during the flood.