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 | From Woodfjorden, Svalbard. Photo: W. Dallmann
In addition to this an unusual amount of rock is
exposed, with little soil or vegetation cover, and can therefore be studied uninterrupted
over long sections. Even if most of the land is glacier covered, Svalbard
provides one of the few locations in the world where an excellent view into
most of the periods of the developmental history of the earth. Taken together,
this makes Svalbard a unique place to study geological processes – it is a
natural geological archive and a laboratory where the geological processes of
the past and present are being demonstrated During most of its geological
history, Svalbard was submerged, and almost continuously deposited sand,
gravel, mud, lime, etc., were progressively altered into bedrock. There is
little soil in Svalbard and no forests or agricultural areas which would hide
the rock formations. The naked landscape permits clear insight into its
geological structure. Although most of the land area is covered by glaciers, Svalbard is
one of the few places in the world which provide excellent access to study
sections of representing most of earth's history. Svalbard is
thus both a natural geological archive and a laboratory where past and present
geological processes are particularly well demonstrated.
Three main geological units
Svalbards geological records can be subdivided into three main units: the metamorphic basement complex, the unaltered sedimentary cover rocks, and unconsolidated deposits.
Basement
 | Midterhuken, Bellsund, Svalbard. Photo: W. Dallmann
The basement complex represents the oldest rocks. These are igneous or metamorphic rocks which after erosion were covered by flat-lying sedimentary beds. The strongest altered rocks occur in northwestern Spitsbergen and in the north of Nordaustlandet. The basement complex has undergone several periods of mountain building, with folding and metamorphism. Traces of the oldest events are almost wiped out by the younger ones. The last main mountain building episode was the Caledonian Orogeny which occurred during the Early Palaeozoic, about 410-440 million years ago. After its cessation, when the mountains had been uplifted, water and weather started to erode the newborn mountain chain.Sedimentary cover rocks
The denudated mountains ended up as huge masses of sand, gravel and mud, which were deposited on river plains and in the sea during the Devonian period, ca. 360-410 million years ago. Later, new depositional episodes formed limestone successions during the Carboniferous and Permian, and sandstone-shale successions during the Mesozoic and Tertiary until about 40 million years ago. During initial stages of the ocean-floor spreading which led to the formation of the North Atlantic and Arctic oceans in the early part of the Tertiary (ca. 60-40 million years ago), the western part of Spitsbergen was folded again to form a new mountain ridge. East of this ridge, from the Isfjorden area to the south, a trough-shaped structure – the Central Tertiary Basin - was formed with the youngest beds in the core and the oldest on the flanks.
Unconsolidated deposits
The youngest deposits are those of Quaternary age which ranges to the present. These are mostly unconsolidated deposits formed during and after the last ice age which ended about 10,000 years ago: moraines, fluvial deposits, beach deposits, talus and scree. Even volcanoes were active during parts of the Quaternary in northwestern Svalbard. Thermal springs which are related to this volcanism are still active.
Geological research at the Norwegian Polar Institute
The geological mapping programme is led by Dr. Winfred K. Dallmann and is focused on areas where there is a lack of information about the geological conditions. The research programme serves to stimulate other research projects by pointing out relevant scientific questions and challenges.
The Norwegian Polar Institute is responsible for mapping of polar regions, including non-commercial geological investigations.
Geological map data are being collected during field excursions and in collaboration with international research groups. The maps are published with detailed area descriptions.
A website for polar geologists
The Polar Institute has its own website for geologists
working in Norwegian polar regions: Geo-NP net.
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