Big rock

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Big Rock or Okotoks Erratic

Big Rock or Okotoks Erratic is an erratic block near Calgary in the Canadian province of Alberta . It is considered to be one of the largest erratic boulders in the world.

Location and geology

The geologist James Hector, who examined the rock in 1863, believed it was part of an underground mountain range because of its size. Big Rock is an erratic block in the Foothills Erratics Train , a group of thousands of loosely lying rocks. Erratic blocks are used when they are extremely large as boulders. The boulders extend in a narrow, approximately 580 kilometers long band from the Athabasca Valley to the eastern end of the foothills near Montana . Big Rock is located on Highway 7 between the towns of Okotoks and Black Diamond , about 18 kilometers south of the city of Calgary.

The Okotoks Erratic originally consisted of a sedimentary rock, a quartz sandstone made of small quartz grains cemented together . This rock had its origin in the Cambrian , namely a period from 542 to 488.3 million years ago. The solidification of the sand was created by the pressure of new layers of sediment in the area of ​​the later shallow sea, the Western Interior Seaway . The pressure of overlying layers and heat solidified the sandstone into a new rock, a quartzite . Quartzites are transformation rocks and are among the hardest rocks, as they consist almost entirely of quartz. The Big Rock is very rugged and therefore offers exposure to weathering processes .

history

In a landslide about 18,000 years ago, several thousand rocky pieces of different sizes in the Rocky Mountains in the area of ​​today's Jasper National Park broke off and fell to the surface of the glacier below . This huge glacier was the Cordilleras Ice Sheet that covered large parts of North America . The glacier carried the rock on its back hundreds of kilometers along the Rocky Mountains in a southeastern direction. After the ice sheet melted, the Big Rock finally remained at its current location in the flat prairie as a boulder. The nearby town of Okotoks is named after him. In the language of the indigenous people living in this region, the black-footed Indians , Okotoks (o'kotok) means large rock . It served them as a waypoint for the crossing point through the nearby Sheep River . In the 1970s, the Okotoks Erratic became the official historic site of Alberta. The rock lay on private land for a long time until the province bought the land in 1987.

The weight of the Big Rock is estimated at around 15,000 to 16,000 tons. It measures a length of 41 meters, a width of 18 meters and is 9 meters high. In the course of time it disintegrated into two large and some smaller parts due to erosion combined with frost.

Big Rock is considered a destination and a tourist attraction. Contrary to the requests of the responsible authorities, it is often used as a climbing rock, despite the risk of further decay. In addition, the existence of historical Indian rock carvings is threatened by climbing.

legend

A legend has grown up around the stone block about an encounter with Napi. Napi (also Napa or Old-man ) combines characteristics of a deity (creator of the world, with all its "faults") but also a lot of human elements; He appears to be partly helping, but also damaging, as a cheater or rogue. So Napi put his coat on the Big Rock when it was very hot and promised the boulder that he could keep it before he hiked on. Shortly afterwards it started to rain and Napi returned to borrow the coat. When the rock refused, Napi got angry, just picked up the coat and left. Then he heard a loud rumble behind him and saw that the rock was following him. He ran away and his friends, bison, deer and pronghorn were crushed when they tried to help him. Napi asked a few bats for help. They attacked the rolling rock and one hit it in the middle and split it in two.

Others

The Big Rock Brewery in Calgary has been using Big Rock as a brand name and popular figure since it was founded in 1985.

Web links

Individual evidence

  1. ↑ a b Government of Alberta, Culture and Community Spirit ( Memento of the original dated February 5, 2009 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. , accessed September 8, 2009  @1@ 2Template: Webachiv / IABot / www.culture.alberta.ca
  2. ↑ Jackson / Leboe et al .: Late Quaternary Geology
  3. ^ Frank B. Linderman: Indian Why Stories . Dover Publications Inc., New York 1995, ISBN 0-486-28800-5 , pp. vi .
  4. ↑ The Legend of the Big Rock. Retrieved September 16, 2009 .

Coordinates: 50 ° 42 ′ 20.7 "  N , 114 ° 4 ′ 34.9"  W.