The Earth Story

This is a drone video of the landslide that occurred in Alta, Norway earlier this week. No one was hurt, and even a dog was rescued after it was able to swim back to shore.

This type of slide is thought to occur on a "Quick Clay" layer, produced as the glaciers departed at the end of the last glaciation. 15,000 years ago - Norway and Scandinavia were covered by a gigantic ice cap. The weight of this ice cap actually pressed down the Earth's crust - like using your hand to push a toy down to the bottom of the bathtub.

When the glaciers melted, the ocean returned, flooding the land you see above the water today. Those ocean waters deposited thin layers of clay and salt on the newly-submerged landscape. But, as the weight of the glaciers was also removed, the land began popping up, bringing this thin layer of ocean sediments above the surface. For the last 10,000 years, sediment from the land buried this thin clay layer, and now houses are constructed on some parts of that landscape. Today, it sometimes only takes a small event, like a rainstorm that dissolves some of the salt, to make that clay layer weak enough to trigger a slide.

-JBB

The three worlds at Alta

From about 4000 BC the smooth cliffs around the Alta Fjord in Northern Norway were the setting of petroglyphs carved by hunter-gatherers living in this area. The petroglyphs (6000 in total) have a great variety in subject and are of special interest because the numerous native animals that are depicted. There are hardly any ethno historical sources about these prehistoric carvings and this makes it hard to discover their background and true meaning. Many scholars have argued that the Alta petroglyphs could be the first signs of a Nordic religion in the area. Around 500 BC the last carvings were made at Alta.

Most commonly depicted are elk (different from the North American elk, the European elk is actually a moose). Furthermore other native animals as bear, reindeer and wolf are depicted as well as human scenes and boats. Most carvings have a storytelling theme. As the image shows red colorants were used for relief.

Scholars have claimed that the location of the petroglyphs on steep cliffs near the sea could represents the Old Nordic belief in a world is divided in three parts; the sky being the upper world, the earth being the middle and the water being the lowest world. The location of the carvings at the shore could mark a contact zone between these worlds and the depicted animals could then be seen as vessels for travelling to the under and the upper world. .

So how is the rock art dated? After the last Ice age on the Scandinavian mainland, new land was exposed and smoothed cliffs appeared along the Norwegian coast. The land started to rise due to loss of pressure from the weight of the former ice, and these cliffs were lifted above sea level. From about 6000 to 7000 years ago nothing happened in relation to the sea and the land and the sea eroded the same cliffs for a long period. The rock carvings were made after this erosion so they cannot be much older than 6000 years. This dating method showed that the oldest carvings are found on higher altitudes whilst the cliffs that were coming out of the sea were used for new carvings.

In 1985 the site of Alta was placed on the UNESCO world Heritage list.

--BO

Image: Karl Brodowsky. A carving of a group of elk at Alta.

References:

Shetelig Haakon & Falk Hjalmar, Scandinavian Archaeology, The Art of the Arctic Stone Age, Oxford: Clarendon Press, 1937.

http://www.alta.museum.no/sider/tekst.asp?side=22&meny=ROCK+ART

http://www.verdensarvenialta.no/english/container3.htm_ _

The three worlds at Alta From about 4000 BC the smooth cliffs around the Alta Fjord in Northern Norway were the setting of petroglyphs carved by hunter-gatherers living in this area. The petroglyphs (6000 in total) have a great variety in subject and are of special interest because the numerous native animals that are depicted. There are hardly any ethno historical sources about these prehistoric carvings and this makes it hard to discover their background and true meaning. Many scholars have argued that the Alta petroglyphs could be the first signs of a Nordic religion in the area. Around 500 BC the last carvings were made at Alta. Most commonly depicted are elk (different from the North American elk, the European elk is actually a moose). Furthermore other native animals as bear, reindeer and wolf are depicted as well as human scenes and boats. Most carvings have a storytelling theme. As the image shows red colorants were used for relief. Scholars have claimed that the location of the petroglyphs on steep cliffs near the sea could represents the Old Nordic belief in a world is divided in three parts; the sky being the upper world, the earth being the middle and the water being the lowest world. The location of the carvings at the shore could mark a contact zone between these worlds and the depicted animals could then be seen as vessels for travelling to the under and the upper world. . So how is the rock art dated? After the last Ice age on the Scandinavian mainland, new land was exposed and smoothed cliffs appeared along the Norwegian coast. The land started to rise due to loss of pressure from the weight of the former ice, and these cliffs were lifted above sea level. From about 6000 to 7000 years ago nothing happened in relation to the sea and the land and the sea eroded the same cliffs for a long period. The rock carvings were made after this erosion so they cannot be much older than 6000 years. This dating method showed that the oldest carvings are found on higher altitudes whilst the cliffs that were coming out of the sea were used for new carvings. In 1985 the site of Alta was placed on the UNESCO world Heritage list. --BO Image: Karl Brodowsky. A carving of a group of elk at Alta. References: Shetelig Haakon & Falk Hjalmar, Scandinavian Archaeology, The Art of the Arctic Stone Age, Oxford: Clarendon Press, 1937. http://www.alta.museum.no/sider/tekst.asp?side=22&meny=ROCK+ART http://www.verdensarvenialta.no/english/container3.htm