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The dramatic landscape with glaciated fjords surrounded by high, alpine mountain tops makes a visit to Hornsund a special experience.
Hornsund is in fact an Arctic Eden, not only for a scientist studying the geology, but also for any visitor getting a chance to gaze at the breathtaking scenery in this beautiful fjord at a high latitude.
From our readers:
Michael Welland went to Svalbard forty years ago.
Picture this scene: Majestic mountains stretching up to 1400 m into the crystal-clear, blue sky, the turquoise, flat fjord just beneath, and in the distance you can rest your eyes on scenic glaciers reaching the water and calving into the sea with a roar. We are at Treskelen, a small peninsula on the northern side of the innermost part of Hornsund, a 30km long and up to 12km wide fjord on the southwestern coast of Spitsbergen. Hornsund is the southernmost fjord on Svalbard and is located within the Sør-Spitsbergen National Park[1].
Hornsund is located on the southwest tip of Svalbard where Precambrian, Paleozoic and Mesozoic rocks are exposed. In Early Tertiary times, shearing between the Barents and Greenland plates caused folding, thrusting and uplift of the rocks, and today Hornsund is a key area for studying the Tertiary tectonic history of West Spitsbergen and the western Barents Sea. Hornsund got its name in 1610, when the British whaler Jonas Poole, with the ship "Amitie", found shelter here during a storm. The crew that went ashore found some horns from reindeer, and because the fjord packed with ice looked more like a "sund" (narrow seaway), the newly discovered area naturally became known as Hornsund. When you come from the Barents Sea towards southwest Spitsbergen, you may recognize the majestic, alpine Horsundtind (1431m) from a distance of 75-85 nautical miles. © Norwegian Polar Institute.
This morning we have walked along the northern shore and examined a colourful succession of sedimentary strata, starting with continental Devonian and Carboniferous clastics, continuing through Permian marine carbonates and ending in Triassic clastic shelf deposits.
Suddenly, the guy up front shouts out: "Polar bear ahead!" We have already passed some impressive polar bear tracks on our way to Treskelen, and there he is, just some 200-250 m in front of us. "Stop, and stay closely together," commands Geir Birger Larsen, the expedition leader from Statoil.
If you do not actually encounter polar bears while onshore, you may nevertheless observe that a representative of these huge predators has been here lately. Note the huge claws and the depth of the imprint.
Photo: Morten Smelror
Geoscientists, as you may be aware of, are usually dedicated to their trade. That is why they not always stay in line when requested. Some have been on Arctic adventures before, and are not easily impressed by the white, Arctic inhabitants. So when the expedition leader decides it is best to keep some distance from the bear, to terminate the field-activities and to call for the zodiack-boat to pick us up, the distinguished Professor David Gee from Uppsala University shouts:
"Give me a gun! I want to see the Jurassic."
Needless to say, his outrageous demand was not accepted.
Upper Permian rocks with numerous marine fossils are exposed on the peninsula Treskelen in the inner part of Hornsund. Hyrnefjellet Mountain is in the background.
Photo: Cecilie Barrere
We are a group of 25 geoscientists from Russia, Norway and Sweden, who have stopped for a day in Hornsund on a field trip around Svalbard. In Hornsund we are guided by colleagues from the Polish Polar Station (Polska Stacja Polarna) at Isbjørnhamna, (Polar Bear Bay) located some few kilometres further west. Our mission is to study the rocks of Svalbard as a part of a joint VSEGEI-NGU-NPD-Statoil project aimed at making a synthesis of the geological history of the Barents Sea, including Svalbard and the Russian Arctic islands (see separate story: "Uniting the Arctic").
In Horsund polar bears are quite common, and if you enter the area from the sea early in the spring, when there still is sea-ice on Brepollen, you have good chances of meeting the king of the Arctic. One reason is that the polar bear's favourite food, the ring seal, breeds in the fjord.
In late autumn, the polar bears migrate through Hornsund when the sea-ice is formed on the eastern side of Spitsbergen. Today, the migration routes are monitored by satellites. From the historical records, it appears that the migration routes have been pretty much the same during the past 80 years.
Wanny, a taxi driver in Tromsø, learned stories about the rough life on Svalbard from hunters she drove to the local pubs in the early 1930's. When she got a chance to go to Svalbard, she did not hesitate, and in only a few days the small, urban woman was transformed into a hunter. She settled at Hyttevika in Hornsund, and in the first season she shot her first polar bear in Isbjørnhamna, close to where the Polish research station is located today. This is typical for how the mountains and places are given a name in Svalbard. For most of them there is an interesting story to tell.
In connection with the International Geophysical Year in 1957, the Polish Academy of Sciences established a polar research station in Hornsund. A reconnaissance group searching the area for a suitable location had been in Hornsund in the previous summer, and selected the flat marine terrace in Isbjørnhamna. The leader of the expedition that established the station was Stanislaw Siedlecki, a geologist, explorer and climber, a veteran of Polish Arctic expeditions in the 1930's, including the first traverse of West Spitsbergen.
The Upper Permian rocks at Treskelen contain well-preserved trace fossils.
Photo: Morten Smelror
The research station, which was constructed during three summer months in 1957, was modernized in 1978, in order to resume year-round activity. Since 1978, the Institute of Geophysics, Polish Academy of Sciences, has been responsible for organizing year-round and seasonal research expeditions to the station. Current full-year activities at the station include meteorology, seismology, geomagnetism, ionospheric sounding, glaciology, atmospheric electricity and environmental monitoring. In summers and winters, the station functions as a base for research on geology, geodesy, geomorphology, glaciology, oceanography and biology.
The coastline in Hornsund has a number of bays with glaciers entering the fjord. Some of these bays first appeared during the last century after the glaciers retreated. As a consequence of the melting glaciers, the whole coastline in Hornsund has expanded. From records going back to 1900, we know that the fjord area has grown by 100 km² in the 20th century, corresponding to an average increase of 1 km² per year the recent decades. The records also tell us that some tide-waterglacier-fronts have stepped back with 125 m to 380 m per year since 1961.
At Brepollen, in the innermost part of Hornsund, we find some of the most impressive glacier scenery on Svalbard. From a 1936 topographic map we know that the Storbreen, Hornbreen and Chomjakovbreen glaciers used to form a continuous glacier front. Today Brepollen is still impressive, but has several separated and isolated fronts. West of the monolithic 487m-high mountain Bautaen, the Chomjakovbreen glacier is reduced forming a separate bay, Svovelbukta.
The geology of Hornsund is complex and diverse, including both Precambrian crystalline and Paleozoic-Mesozoic sedimentary rocks. Its interesting geology and glaciated landscape have for decades attracted geologists and geo-morphologists to this area. The Proterozoic to Cenozoic strata reveal a prolonged and complex tectonic development, consequently, the Hornsund-Sørkapp region is a key to the understanding the geological evolution of Svalbard and the western Barents margin.
The middle part of the Hornsund area is characterized by a distinct alpine landscape, including the 1431m Hornsundtind to the south and Sofiekammen and Gnålberget to the north. These mountains consist of mainly Lower Paleozoic carbonates, commonly referred to as the pre-Old red basement rocks on geologic maps. Further east, the landscape changes character. Gentle, rounded mountains composed of sedimentary rocks dominate. The sedimentary strata represent rapidly changing terrestrial to marine depositional environments, making the large exposures a symphony of colours.
Small fossil bivalves are preserved in the Upper Permian rocks at Treskelen.
Photo: Morten Smelror
During the Devonian the region experienced extension. This was followed by Early to Middle Carboniferous extension and local transpression forming major highs and basins filled with coarse continental clastic sediments. During the Permo-Triassic subsidence and marine flooding followed, interrupted by periods of uplift and erosion. Similar development continued during the Jurassic and Cetaceous, terminating with a major uplift phase in the Late Cretaceous to earliest Tertiary. During the Early Tertiary, the area experienced contractional-transpressional and extensional tectonics, and Paleocene-Eocene sediments were deposited in the Central Tertiary Basin and smaller local grabens. This was in the Early Tertiary, when Greenland and Svalbard collided. If you follow the slope towards Treskelen, and continue across the peninsula towards Brepollen, you can see the succession of Devonian to Jurassic sedimentary strata as described above.
Structural geologists will appreciate the large Hyrnefjellet anticline forming the Hyrnefjellet mountain. For palaeontologists, paradise is found on Treskelen, a fantastic floor of Upper Permian carbonates with numerous marine fossils is exposed.
On the perfect, sunny day we were in Hornsund, only a single sail-yacht visited the fjord. On this coast, however, the calm and sunny days are not frequent. Low pressure accumulates on the western coast of Svalbard, and in Hornsund, the combination of high mountains, large valleys, vast glaciers and a long fjord result in unstable weather conditions. When there is complete calm outside the coast of Western Spitsbergen, there may well be heavy wind in Hornsund coming from the east. The wind behaves as if it were running through a tunnel between east and west, across the glacier and in to the fjord.
Updated: 03.01.2008 11:33 by Alf Kvassheim
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