There were two landing options this morning. For those who were up for a 6 miles tundra hike, there was an early zodiac departure to a drop-off point. This group would hike to the landing place for the rest of us. We went to the prep lecture last night and were all ready to sign up until we learned the walkers had to hike in their expedition-issued knee high muck boots.
The ambitious few, at their landing site. The brightly colored corrugated huts are for hunters and emergency supplies.
Sydka is a beautiful low landing place with a long history. Hunters have passed here for at least 4,000 years. The most recent settlers were from the Thule Culture, the last prehistoric Inuit society. It developed in North America around 1000 AD, and slowly spread eastward. They settled in the Scoresbysund Fjord from roughly the 1400s to the late 1800s. Our landing place today is an archeological site, dotted with remnants of their hunting settlement.
This is an ancient dug out lodge, with the basic shape of an igloo: a long entry tunnel opening into a round room. The roof may have been made of turf, supported by stones or long rib bones from whales. It’s too windy here now for much snow to accumulate along this shore, but it’s possible they could even have cut ice blocks as building materials in the past.
Skull and jawbone - musk ox
Burials were in the open, with rocks piled in a circle around the body. This is one of two burial sites we passed.
To protect the environment, everyone goes through the vigorous boot-washing machine after each visit ashore.
An afternoon lecture on Greenland geology helped explain the tortured rock faces we saw yesterday in Øfjord. I scrambled to type notes, but it was a lot of information delivered pretty quickly and I’m not going to fact check it all. So don’t quote anything below on a geology exam.
Over 4/5 of Greenland is covered by ice, centuries of compressed snow captured in a 1.7 million square kilometer ice sheet. Only Antarctica and Greenland have ice sheets, holding a combined and astonishing 68% of the fresh water on Earth. The significance of this immense reservoir of frozen water and its accelerated melting due to climate change cannot be underestimated.
The U-shaped valleys in the fjords were carved by ice, and the V-shaped valleys by water. Fjords are created by the flooding of U-shaped valleys, as the glaciers melt and retreat. Scoresbysund Fjord is the largest and deepest fjord system in the world, over 350 km (220 miles) As sediment washes from the mountains down the fjord, the deepest part is furthest from the entrance. While the average depth is 500 m (1640 ft), its maximum depth is 1450 m (4757 ft, or 0.9 mile).
When I saw this Fram-sized iceberg floating next to the ship this morning (and not far from shore) and considered that 90% of an iceberg is below the water surface, I thought it must get pretty deep, pretty fast.
Several techniques, such as ice-penetrating radar, are employed to study the rocks under the ice. Standard geologic surveys are used in the exposed area.
There are four main types of rock in the fjord regions through which we’ve been traveling:
1. Very very old rocks. The whirling mass of hot gases that formed the Earth began to solidify around 4.6 billion years ago. Some of the oldest rocks on Earth (3.8 billion years old) are in Greenland. This rock is known as the ancient shield, or Greenlandic Shield. Some of the earliest forms of life may have emerged in West Greenland.
2. Old mountains - created when tectonic plates moved Greenland into Scandinavia, causing mountains to rise, and rock to partially melt from the pressure. There mountains have twisted faces and veins of different colors, often red from iron oxide.
3. Sedimentary rock - about 400 million years ago. Sandstone, contains fossils. Still being eroded today by ice and water.
4. Volcanic rock. The plates between Greenland and Scandinavia began to reverse course and separate about 200 million years ago. By 60 million years ago, the Atlantic Ocean was fully open between them. As Greenland drifted for eons over a magma plume (where Iceland, with its geysers and active volcanoes, is still being formed), volcanic rock formed in Greenland. This is similar to how Hawaii has a chain of islands, with the oldest long dormant and the youngest still volcanically active.
Some favorite glaciers as we cruised back towards the entrance of the Sound:
Greg deduced that this one must have rolled when it first hit the water. The squared-off shape is usually a giveaway for a newer glacier, but the grit coating its surface must have accumulated while scraping down a glacial valley.
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