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The coastal road (state highway 17) from Holandsfjorden to Nesna
93 Locality 39 - Blokktinden, Tjong
On the road to Tjong and onwards to Reppa there is a good view towards Blokktinden and its
very large avalanche cone. Blokktinden is carved in granitic gneiss and belongs to one of the
Precambrian basement windows. Strong vertical jointing in the bedrock is one of the reasons for
the large quantities of scree material which have accumulated here.
The main shore line forms a break in the avalanche slope and can be seen as a horizontal line.
Here it represents the marine limit and is clearly developed in the fallen material. This means that
most of the cone is a little older than the last part of the Younger Dryas. Probably most of the
stoneblocks fell from the mountain wall a little after the mountain emerged from the ice masses
12,000-11,000 years ago. The climate during the first part of Younger Dryas time was very cold
which enhanced fracturing of the rock walls and initiated stone-block production.
Blokktinden with its 400 m avalanche cone, looking south from Tjong. Photo: Terje H. Bargel.
94 Locality 40 - Nordværnes
On a branch road, about 15 km from Straumsvika and only a few hundred metres from
Nordværnes, is a body of peridotite (olivine/pyroxene rock). It is easily seen because of ifs
reddish yellow alteration colour. Parts of this body, particularly the marginal zone and
intersecting veins, are very special. In a groundmass which consists mostly of orthopyroxene
there are olivine crystals 5 cm to 1 m in length and randomly orientated. The rock is igneous, but
the special texture is the result of alteration processes (metamorphism).
Landscape with ochre-coloured weathered peridotite at Nordværnes. Blokktinden (locality 39) in
the background. Photo: Terje H. Bargel.
95 96 Locality 41 - Ferry trip Jektvika -Kilboghamn (60 min.)
The ferry quay at Jektvik lies approximately where the glacier margin of the inland ice lay 12,300
years ago (see map page 93). It is thought that the marginal zone crossed Åsen (202 m above sea
level) southwest of Jektvika. From the ferry we can see Rødøyløva to the northwest, with its
characteristic island profile in which the uppermost part of the mountain ridge resembles the head
of a lion. Rødøyløva consists of red, granitic gneiss. Other islands to the west are Renga and
Rangsundøy which consist partly of granitic gneiss, partly of altered sedimentary rocks such as
micaceous gneiss and marble.
After passing Telnes there is a good view of Melfjorden to the east. The ferry crosses the Arctic
Circle here. The glacier margin crossed Melfjorden 12,300 years ago (A-glacier margin line, see
map page 22). The route of the ferry between Jektvik and Kilboghamn may have been ice-free as
early as 12,300 years ago. The fjord was probably full of icebergs at that time and the only
'tourists' who visited the area must have been whales or other marine animals. In Nordfjorden, a
branch of Melfjorden, there is a permanent seal colony today. This is a protected area.
Locality 42 - Kilboghamn
At Kilboghamn there are also indications of the glacial margin 12,300 years ago. just south of the
ferry landing (800 m} there is a gravel pit opened in a glacial marginal deposit with large
transported blocks on its surface. This deposit is thought to represent the A-glacier margin.
From Øresvika we can see eastwards and inwards to Gjervalen which is the innermost arm of
Sørfjorden. About 10,000 years ago thick tongues of ice extended down to the fjord, 3-6 km from
Øresvika.
97 98 Map of the ice situation 10,000 years ago. Two glacial tongues from the inland ice extend down
to the fjord and icebergs drift in the sea outside the ice margins, filling parts of the fjord basin.
This is in sharp contrast to the situation prevailing today.
99 Locality 43 - Tonnes
After passing 0resvika one can take a 15 km long side road to Tonnes before returning to, and
continuing on the main road. From Tonnes there is a good view of a cave on the mountain side to
the northeast. This cave lies about 100 m above sea level. Many fallen blocks and much rock
cover the rocky threshold at the opening. The cave is 170 m long and must have been excavated
and shaped by the sea. It follows the contact between mica-schist and banded gneiss which is
parallel to the strike direction of the gneisses here. In the sand on the floor of the cave aluminium
sulphate has been found. In former times this was used by the local population for tanning
leather.
100 From Tonnes there is a good view of Hestmannen (Hestmona). From the shipping channel this
feature looks like a man riding a horse (hest), therefore the name. It can also be seen from
highway 17 when driving along the northeast side of Aldersundet. Hestmannen consists of micaschist, but the smallest of the two summits is granitic.
Hestmannen seen from Kvaroya.
Locality 44 - Aldersundet
The nearest island on the west side of Aldersundet is Aldra, its highest summit being 967 m
above sea level. It consists for the most part of granitic gneiss, but there is a belt of mica-schist
and marble in the low ground where the houses are located. A marked shore line is carved in
thick till and is about 90 m above sea level.
Above the sports ground in Aldersundet, about 1 km from the road, there is a marginal moraine
deposited outside one of the many cirque glaciers of Younger Dryas time. This cirque glacier
extended down to the sea level at that time. This is about 90 m above the present level which
corresponds to the marked shore line on Aldra.
101 The strandflat seen from Grønsvika fort (fortress).
102 The Træna islands seen from the east. Notice the almost flat-lying layers of gneiss in Trænstaven
(to the right in the picture, 336 m a.s.l.), and also the contrast between the strandflat and the high
mountains (relics of erosion). Photo Terje H. Bargel.
Island domain to the west
From Stokkvågen the ferry and express boat service goes to the islands to the west, including
Lurøya, Lovunden and Træna. The islands consist of the same rocks as those on the mainland, i.e.
gneisses and mica schists of Precambrian and Cambro-silurian age, Younger sedimentary rocks
which make up most of the continental shelf are not present on the islands. Several islands rise
above the strandflat and have characteristic topographic profiles. Lovunden (623 m above sea
level), is well known and has a colony of puffins living in the scree on the north side: The
mountains of Træna, including .Trænstaven (336 m above sea level) lie on the Island of Sanna,
At the foot of the mountains there are several caves and rock surfaces developed when the sea
level was higher than it is today. The most well known of these is Kirkhelleren where excavations
have revealed traces of settlement in several periodes from both the Older and Younger Stone
Ages and from the Iron Age.
103 Locality 45 - Grønsvika fort
Viewing point. Parking at cafe.
The fortress was in use during World War II. It is now being restored as a historical site from that
time. The rock is a greyish white, quartz-feldspar-rich gneiss. It is of Precambrian age and
belongs to the Sjona window. From the highest point within the fortress there is a view
westwards to Lovunden, Lurøy and the distinctive strandflat.
Locality 46 - Bogen
Stopping place towards the sea at Silavågen.
The rock at this place is the usual, light-coloured, pinkish, bed-rock gneiss in the Sjona window.
It consists of red feldspar, grey quartz and black hornblende as well as a little magnetite. These
minerals are also present in small irregular pegmatites (coarse-grained intrusive rocks) and are
easy to identify.
Locality 47 - Flostrand
Stopping place in former quarry, about 3.5 km west of Flostrand.
The rock is a grey, hornblende-bearing basement gneiss. In the gneiss there are several lightcoloured pegmatite veins. In connection with some of these veins there is a network of cracks.
The cracks are filled with sulphide-bearing minerals and ankerite, CaFe(CO3)2. Weathering of
these minerals gives the gneiss a rusty appearance for half a metre or so from the veins. The veins
themselves are only a few decimetres wide.
A narrow, dark, biotite-rich vein can be seen in the road-cut. This follows the planar structure in
the gneiss and is similar to that in the previous locality, an altered diabase dyke.
During the deglaciation 10,000 years ago there was a fjord connection between Sjona and
Ranafjorden via Utskarpen. This lasted several thousand years, but 5,000-6,000 years ago the
land uplift had progressed so far as to close the fjord connection and cause the Utskarpen area to
be dry land.
104 105 Locality 48 - Sjonfjellet
View point from the stopping place just below the former cafeteria. In good weather this is a very
good view point. Lovunden and Træna can be seen far out to sea and to the north, and northeast
there is a view to the almost naked terrain of the granite areas on the opposite side of Sjona. This
shows how important the composition of the rock is for the vegetation. In the mountain side to
the south a sharp boundary can be seen. This is considered to be the thrust boundary for the
Helgeland nappe complex which is the uppermost nap-pe unit preserved in the Caledonian
mountain chain.
White, pegmatite gneiss in basement gneiss in the abandoned quarry west of Flostrand. Notice
the rust zone on each side of the pegmatite vein.
On the north side of Sjona an elongate cirque-shaped valley can be seen. The river has cut down
through a threshold at the mouth of the valley. The height of the threshold is about 200 m above
sea level and probably represents the approximate height of the valley floor in the original river
valley. Later erosion by glaciers has given the valley its basin-like form, but before that, the
106 valley can have attained its 'hanging' character by glacial erosion which shaped and lowered the
level of the fjord valley.
Sjona and Ranafjorden were connected when the area between Nesna and Utskarpen in the
distant past was an island. The map shows this connection as it was about 7,000 years ago.
107 108 Earthquakes and recent land uplift
The coast of Nordland is known as an area where earthquake activity occurs from time to time.
The biggest earthquake, about 6 on the Richter scale, occurred in the Rana area in 1819. In recent
years, several registrations have been made which indicate that in some areas at least, land uplift
is not a reaction to relief of pressure following former loading by ice. These crustal movements
are related to movements in the Earth's interior and are called neotectonics. Neotectonic
movements involving land uplift of the order of 1-3 mm per year have been registered in some
areas. Movements can also occur along old faults and joint zones. This can be of importance for
technical installations in the bedrock.
The Båsmoen fault west and north of Mo i Rana is a fault zone which is probably still active
today. It can be seen as a pronounced escarpment cutting across the landscape (marked with
arrows) form Utskarpen in the west to the mountain area southwest of Storforshei in the east.
Photo: Odleiv Olesen.
109 The road section Mo i RanaSaltfjellet (E6) and Mo i Rana –
Umbukta (E12)
110 The road section Mo i RanaSaltfjellet (E6)
The road proceeds along the Rana River, through Dunderlandsdalen. This area is well known,
geologically speaking, for its iron ore deposits and limestone caves. In road-cuts it is common to
find mica-schist of different types. Even though Dunderlandsdalen is rich in marble there are not
many places where good exposures of this rock occur along the E6.
During the Caledonian orogeny the rocks in this area were thrust over the Precambrian basement
and little by little large nappe complexes were built up. These complexes cover large areas in
central parts of Nordland. The orientation and shaping of Dunderlandsdalen is largely determined
by the structure of the bedrock. For long sections the valley lies parallel to rock boundaries (strike
direction). At some places, however, the valley cuts across the rock boundaries. This coincides
with zones of weakness in the bedrock (joints) which have locally determined the direction of the
valley. The valley is usually narrow at such places, as for example at Åenget (5 km east of Mo i
Rana), Illhollia and Storvoll.
Karst landscape and caves
The area around the Rana drainage system together with Dunderlandsdalen contains much
marble, limestone altered at high pressure and temperature during the Caledonian orogeny in the
Paleozoic. The limestone is relatively easily dissolved by water containing carbon dioxide.
Surface water wears down the marble to such an extent that it changes the appearance of the
landscape (karst). The surface becomes very uneven and dissected by channels and deep holes. In
joints and cavities the water eats away at the rock so that a network of underground channels
develops. In Dunderlandsdalen there are many streams that flow through the marble zones. More
than 30 such streams have been observed between Storforshei and Bjøllånes. Some of the
underground channels are so narrow that they are unable to drain all the water during periods of
flooding. The surplus water follows surface channels down to the valley floor where it reunites
with the rest of the water masses. Such surface channels are usually dry for most of the year.
Examples of underground channels are Litlåga in the western mountain side at Dunderland and
Pista near Krokstrand.
111 112 Where rivers and streams have taken new courses through the limestone the older underground
channels are more or less dry. It can be exciting to explore such caves and they have a special
attraction for people looking for adventure but who do not suffer from claustrophobia. The caves
are often branched and very different both as regards size and shape. The passage-ways rise and
fall, sometimes in steep cliffs. Proper climbing equipment is necessary to pass the obstacles.
Many caves open high up in the mountain sides and at other places, which shows that they cannot
have been water-filled as the drainage conditions are today. Age determinations show that some
caves have existed for more than 350,000 years and must therefore have survived several iceages. It is difficult to decide to what extent the caves were formed during the ice-ages but many
show signs of ice action. Several caves are filled with gravel and stones with a foreign origin,
indicating ice transport.
113 At the end of the ice-age the sea was 120-125 m higher in relation to the land areas than it is
today. The Dunderland valley was a fjord as far as Dunderland, 40 km from the present day
fjord.
114 Locality 49 - Mo i Rana
The central parts of the town are located on large river terraces of sand and gravel. The largest
terraces are between 40-50 m above present day sea level. They were formed in front of the
mouth of the Rana River 6,000-8,000 years ago. In this period (the Tapes period) rapid uplift of
the land ceased and a period of stagnation or very slow uplift followed. Jernverket (the iron
works) lies on one of the large terraces (53 m above sea level) where it was easy to build a large
industrial plant. The superficial deposit beneath the plant is more than 100 m thick.
115 The road section from Mo i Rana to Røssvoll passes through quartz-rich mica-schist, limebearing mica-schist and an area with volcanic rocks. Age determinations show the latter to be 450
million years old.
Locality 50 - Åenget
When driving eastwards along the E6 from Mo i Rana river terraces at several levels can. be
observed on the opposite side of the Rana River. At Åenget, 4 km east of Mo i Rana, the Rana
River turns sharply (90o) towards the NNE and the valley narrows (see photo page 112 top).
River terraces of sand are deposited above the road in the bend. Some of the sand layers contain
shells of different species which lived 8,000 years ago when the sea level was about 50 m higher
than today.
116 Locality 51 - Røssvoll
At Rossvoll the valley opens out and large river flats occupy the floor only a few metres higher
than the river. From the northwest a large branch valley emerges from Raudvassdalen and
Langvatnet in which large river terraces were deposited at several levels. The airport is built on
such a terrace about 70 m above sea level corresponding to the sea level 8,500-9,000 years ago.
The terraces represent the Rana River's deltaic plains from that time. A branch road from the E6
leads northwards past the airport to Langvatnet and Raudvassdalen. Signs point to the geological
sites, Grønligrotta and Østerdalsisen.
Locality 52 - Grønligrotta
In the area north of Langvatnet there are several limestone caves. Gr0nligrotta is the best known
cave in Scandinavia and more than 10,000 tourists visit it each summer. The guided walk for
tourists is 400 m long and electrically lit.
Grønligrotta was discovered during the first settlement at Grønlia 250 years ago. The cave now
has two openings in the steep mountain face, 200 m above the floor of Raudvassdalen but earlier
there must have been several tunnels in from the valley. A network of tunnels falls downwards in
the mountain and the deepest lies 107 m under the entrance. The total length is about 2,000 m. A
stream flows through parts of the cave forming waterfalls and rapids. The cave is largely formed
117 at the boundary between the mica-schist and the underlying marble. The schist often forms the
roof.
In Kapellet ( «the chapel» ), on the tourist route, a block of granite has become wedged between
the cave walls. Since granite has not been found in the marble and schist rocks at Grønlia the
block must have come from some distance. The nearest granite areas lie east of Svartisen, almost
10 km away. The block must have been transported to the cave by the glacier and washed into it
by melt water from the ice. This may have taken place during the last glaciation, 10,000-30,000
years ago, or even in an earlier ice age since the cave was probably formed several hundred
thousands of years ago.
Map of
Grønligrotta.
(According to
Oxaal 1913). The
dotted line shows
the tourist trail
and the blue line
where the stream
is visible in the
cave.
118 119 Locality 53 - Østerdalsisen
If we continue northwards in Raudvassdalen and in Svartisdalen we arrive at Svartisvatnet. A
boat operates on the lake during the tourist season. From the end of the lake there is a walk of 2-3
km to Østerdalsisen which is one of the best known and most visited glacier tongues from
Svartisen.
This glacier has an interesting history as regards climate and extent during the last 250 years. Its
maximum extent was around 1750. The outer limit shows clearly in the terrain, especially on the
south side of Østerdalsvatnet where there is a marked morainic ridge. The rock surface inside this
limit is washed and scoured and almost free of vegetation.
The border is easy to see from the boat on Svartisvatnet. The glacier lay in the same position for
more than one hundred years. In 1890 the glacier front began to retreat slightly from
Svartisvatnet. In the west, melt-water from the glacier drained towards Glåmdalen.
At the turn of the century the westerly part of the glacier tongue shrunk so that a small lake was
formed in front of the ice-front. As the glaciation continued over the next 40 years this glacierdammed lake became larger and larger and was called 0sterdalsvatnet. Gravel, sand and mud
were deposited on the floor of the lake. A thick succession of layered sand and gravel
accumulated at the outlet to the west, towards Glåmdalen.
In 1941 a sudden tapping of the water took place under the ice towards the east and down into
Svartisvatnet. Fortunately, this tapping took place during a period of two weeks and no
catastrophic situation arose. But the tapping became a yearly event and increased in extent such
that the level of Østerdalsvatnet, by the middle of the fifties, fell by 60 m and 50 million m3 of
water flowed across to Svartisdalen. Calving icebergs filled the whole lake and a very dramatic
situation became apparent. A tunnel was driven eastwards from Østerdalsvatnet in 1959 to avoid
the risk of a catastrophe and to keep the water level constant.
The glacier continued to diminish during the following years. By 1987 it was so thin that large
pieces of the ice-front floated upwards and the whole lake became filled with large icebergs.
Today the ice-front has begun to retreat up onto the land but calving still continues at the front.
The steepness of the front means that calving and avalanching of iceblocks is even more
dramatic. In the summer of 1989 a block of ice with a volume of several hundred cubic metres
120 became detached from the glacier. It fell into the water and gave rise to a huge flood wave which
swept far in over the land. One person was caught by the wave and died. It is therefore important
to keep well away from the water. Warning-signs have now been erected to indicate the danger
zone.
Belemnites (fossils) have been found in glacial lake deposits in Østerdalsvatnet and in the river
fan in Svartisvatnet where the river from the glacier emerges. Belemnite is the name of a group of
cuttlefish (squids) which lived in the Mesozoic, especially in the Cretaceous, but which died out
in the Tertiary. If these fossils have been washed out of till from Østerdalsisen it opens up a very
interesting geological perspective since no rocks younger than the Cambro-Silurian have been
found in the Svartis area.
121 122 Road-map for the area Mo i Rana -Østerdalsisen -Melfjordbotn.
123 Locality 54 - Melfjellet
From the road junction at Langvatn a road goes along the north side of Melfjellet to
Melfjordbotn. Langvatnet lies in a terrain of marble and mica-schist whilst the mountain area to
the west consists of Precambrian granitic gneiss.
From the highest point on the road on Melfjellet there is a view towards Høgtuva (1,268 m) to the
south and to Svartisen to the north. The westerly part of Svartisen also lies on hard Precambrian
gneisses. Along the valley between Høgtuva and Svartisen occur mica-schists and flagstones
which are easily broken down by weathering and erosion. It is easy to see where the boundary
towards the younger, overlying rocks goes since the latter are much darker in colour. Flagstones
are exposed in road-cuts from Melfjellet down to Melfjordbotn. Close to the road several
cylinder-like pot-holes occur in the flagstone. The largest are 2-3 m in diameter and 4-5 m deep.
The pot-holes are formed by melt water from the inland ice. Swirling streams of water caused
stones to rotate and excavate the holes.
124 Background radiation
The bedrock can contain minerals which are radioactive. This gives rise to a natural background
radiation, the intensity of which is related to the radioactive minerals present and their volume. In
general it can be said that rocks with a sedimentary origin have lower background radiation. One
exception is black schist which often gives higher radiation than other common sedimentary
rocks. Granites and granitic gneisses are often more radioactive and the area around Høgtuva is
such an area. However, the radiation is not high enough to constitute a health risk for people
travelling in the area.
125 Several pot-holes can be seen in the bedrock close to the road over Melfjellet. The pot-hole
shown in the picture is c. 4 m across and is partly cut by the road. Photo: Terje H. Bargel.
View northwards from the road to Melfjord, Flat-lying rocks give rise to a special type of
landscape with flat, plateau-like areas bounded by vertical cliffs. Here we see Øverloftet which
consists of mica-schist and amphibolite whilst Svartisheia in the background to the right consists
of granitic gneiss of Precambrian age. Photo: Svein Gjelle.
126 Locality 56 - The Jordbru area in Plurdalen
From Røssvoll a side road leads eastwards to Plurdalen. This valley is parallel to the strike
direction of the rocks. Long, narrow zones of marble alternate with lime-bearing micaschist.
These rocks weather easily giving a good soil and lush vegetation. The farm Jordbrua is reached
26 km from Røssvoll. From here, a private road continues a further 6 km to Kaldvassdammen. A
little over a kilometre from Jordbrua is Steinugleflåget (signposted at the road side). A path leads
up to the edge of this circular, crater-like depression with a diameter of about 30 m. In the bottom
of the depression there are openings to a system of underground passages.
It is 500 m from Steinugleflåget to Trollkjerka which is also a large collapse structure with steep
walls and which opens out in a semicircle towards Plura. The road runs just along the cliff edge.
There is an entrance to the cave in the floor of the structure and this probably represents the
entrance (gully) to Plurals underground channel as it was far back in time. Plura flows
underground for about 3 km today.
Sprutforsen lies a further 2 km along the road. It lies where the underground stream-channel of
Sprutbekken emerges in the valley side and gushes profusely when the flow of water is great. The
cave system in which this stream runs is over 1 km long and part of Jordbrugrotta, a system of
over 3000 m, with several entrances.
The road continues past Sprutforsen and a further 2.5 km up to Kaldvatnet. A walk starting from
the parking area at Sprutforsen can be recommended. Follow the road a little way past
Sprutforsen to the marked path to Sauvasshytta. The path starts off in mica-schist but soon passes
into marble terrain. Here one can see how the streams alternate between underground and surface
channels.
127 The Jordbru area with Steinugleflåget, Trollkjerka and Sprutforsen. The extent of the marble is
shown by the blue colour and other altered sedimentary rocks are shown in green.
128 129 130 Locality 56 - Illhollia
From Røssvoll and 3-4 km along the E6 and Ranaelva (Rana River) the road enters a very narrow
part of the valley. The river has dug deeply into the bedrock along a zone of weakness here. The
V-shaped cross-section of the valley shows that river erosion has dominated and that the inland
ice has not participated in the erosion. An explanation for this is that the ice moved more or less
across this part of the valley instead of along it.
Locality 57 - Road-cut 500 m east of Storli camping
A garnet mica-schist invaded by a white intrusive rock (trondhjemite) is found here. The micaschist has beautiful red garnets and is rich in white mica. A little black mica together with greyish
quartz and white feldspar are also present. The veins contain white quartz and feldspar and
sparkling white mica (muscovite). The trondhjemitic veins have invaded the mica-schist along
the schistosity planes. At some places they can be seen to cut the schistosity. The rocks here lie in
131 the lower part of an old thrust sheet (nappe) and the associated zone of thrusting follows
approximately the river.
From Storlia and further up the valley to Storvoll the road passes through a terrain with abundant
marble. Calcitic marble, dolomitic marble and lime-bearing schists alternate with each other but
there are very few good exposures easily accessible from the main road.
132 Locality 58 - Storforshei
Rana Gruber's plant is located at Storforshei. The largest iron ore deposit in Rana mined in large,
'open pits. The ore is transported by-rail to the beneficiation plant in Mo i Rana where iron
concentrates are produced and supplied to the international market.
The iron ore is an altered sedimentary deposit. It has been known for over 200 years but has been
commercially exploited only in the present century. Up to 1940 it was in production in three
separate periods, the longest of which was 4 years. An English company mined the deposit and
the last period of operation ended when World War II began. After the war the Norwegian state
took over all shares in the company and production on a large scale began in the mid-sixties.
Since then Rana Gruber has mined about 2 millions tons of ore a year. Norsk Jernverk in Mo i
Rana was purchaser of the ore when they produced pig-iron, and at that time Rana Gruber was a
part of Norsk Jernverk. Today the mines are a separate, independent company.
Rana Gruber produces an iron concentrate which is sold to smelters in Europe and the USA. In
recent years some of the iron concentrate has been refined by micronization and the product used
as black pigment in car tyres and concrete, among other things.
Locality 59 - Eitråga
The farms above the road lie on soil derived by weathering of the rock while those below the
road lie on river sand. Here there is a road-cut in the calcareous mica-schist which is typical for
Dunderlandsdalen. It consists for the most part of calcite, quartz, muscovite, biotite and garnet
together with characteristic thin slivers of yellowish-white, fine-grained dolomite. It weathers
easily, has a reddish-brown weathering colour and gives a fertile soil.
A little less than 3 km further up the valley from Eitråga, the road passes the railway used by
Rana Gruber for transport of their products. The railway crosses the E6 and the Rana River by a
bridge and enters a tunnel leading to an ore silo inside the mountain. The rock taken out during
tunnelling has been used to build the railway track.
133 Locality 60 - Litlåga, Dunderland
The area at Dunderland is characterized by zones of marble and mica-schist which strike parallel
to the valley. Tributaries to the Rana River cross rock boundaries and many flow in underground
channels through the marble zones. One of these streams is called Litlåga and it flows for several
hundred metres below the surface in the lower valley side. It emerges again from several tunnel
openings just above the E6 and unites to form a surface flow down to the Rana River. In periods
of flooding the underground channels cannot handle all the water and the surplus is forced to
follow a channel on the surface (flood channels).This channel is usually dry throughout the rest
of the year.
134 Map of Litlåga's drainage pattern.
135 136 Locality 61 - Storvoll
Storvoll is a good starting point for walks in the terrain. Here four other valleys open out into
Dunderlandsdalen. Stormdalen, a lush and beautiful valley with much lime-bearing bedrock and
glacial till, enters from the west. At the opening of the valley, at Granneset, lies Nordland's most
northerly natural forest of spruce.
Tespdalen and Bjøllådalen come from the north where the traffic between Salten and Rana went
before the road and the railway across Saltfjellet were built. From the south comes
Messingadalen.
The valley floor at Storvoll is filled with sand and gravel deposited by glacial rivers during
deglaciation about 9,000 years ago. At Storvoll we leave the Rødingsfjell nappe complex and
enter the Seve-Køli nappe complex (see drawing on page 34). Here the degree of alteration is
lower, that is to say the rocks have not been exposed to such high temperatures and pressures
during the mountain-building processes as was the case for the Rødingsfjell nappe complex. It is
easier to break down weakly metamorphosed rocks than those more highly metamorphosed. This
has caused the valley to be parallel with the front of the Rødingsfjell nappe. The upper part of
Dunderlandsdalen starts about 3 km from Storvollen and just after the road has passed under a
railway bridge. This is developed in low metamorphic mica-schists, phyllites and marbles. The
nappe front with the high metamorphic rocks can be seen above the timber-line on the southwest
side of the valley. Hard granitic rocks make up the mountains of the east side of the valley.
137 The Nasa silver mine
About 8 km from Krokstrand there is a side road to the east. When the snow has disappeared it is
usually safe to drive along it for a short distance. From this road an old, marked track leads to the
Nasa silver mine which lies about 1,000 m above sea level and just across the border to Sweden.
It is about 10 km from the E6 and involves climbing 500-600 m. silver-bearing galena and zinc
blende were the most important minerals in the deposit. It was in production from 1635 to 1659
and from 1770 to 1810. At the time the deposit was found there was disagreement regarding the
course of the state boundary between Sweden and Denmark/Norway. At the most there were
almost 100 men permanently employed at Nasafjell. The ore was transported about 50 km to a
smelter at Silbojokk where a small community grew up. On Nasafjell itself a church was built.
138 Here we find probably Scandinavia's highest burial site. Both the Silbojokk community and the
mine on Nasafjell were destroyed by a Norwegian military force in 1659.
Traces of mining on Nasafjellet are still visible in the terrain almost 200 years after the mine was
abandoned. The trench to the right in the picture cuts the remains of an ore vein that has been
exploited. Here one can still find ore minerals such as silverbearing galena (the small picture).
Photos: Ingvar Lindahl and Lars Petter Nilsson.
The road section Mo i Rana -Umbukta (E12)
This road section (E12, see map page 110) lies entirely in the Rødingsfjell nappe complex. The
area is rich in ore deposits and several have been mined though none are in operation today.
Mofjellet Gruber which was mined for zinc and lead lies in the mountain on the south side of Mo
i Rana. It was closed as late as 1987 after having been in operation for about 100 years,
admittedly with several periods of closure.
139 Locality 62 - Bertelsberget (Sølvgruva)
Just outside Mo i Rana a road branches off to the south to Mofjell Gjestegard (Inn). Follow the
signs further on to Bertelsberget about 2 km past the road to the inn. From here, a path 800 m
long, leads to a 300 years old mine from which silver-bearing galena was produced. The mine
adits are water-filled about 20 m from the portal. The deposit lies in a muscovite and pyritebearing gneiss.
From here there is a good view of Mo i Rana and the large river terraces on which the town is
mainly built. Jernverket lies on the largest of these terraces. One can see two other mines from
here. In a west-northwest direction, on the outskirts of Mo i Rana lies Bosmogruva. This pyrite
mine was closed in 1937 after being in operation more or less continuously since 1894. In a
north-northeasterly direction lies Rana Gruber's open pit where iron ore has been mined as well
as calcite and dolomite. The mine is still in operation.
The first 11-12 km of the E12 eastwards from Mo i Rana pass through calcareous mica-schist.
This has white quartz lenses with pale brown eyes of calcite in them. The main minerals in the
rock are calcite, quartz and mica, but there is also a significant content of zoisite (a calcium
aluminium silicate) and garnet. Further towards Raudvatnet the road passes through gneisses and
amphibolites.
140 Locality 63 - Mosgruva
About 20 km from Mo i Rana, at the northwest end of Raudvatnet, a narrow gravel road branches
off to the north. This road, about 1 km long, leads to Mosgruva, a pyrite deposit which has been
mined, but is no longer accessible. Signs have been erected to warn the public about the danger of
mine openings in the area. Be careful! The mine was operated for a few years around the time of
World War I. Lumps of pyrite can be found lying around on the ground. Many of these have a
rusty surface but gold-shimmering interiors. The rock frequently has a reddish surface on account
of the sulphide which rusts easily.
141 Locality 64 - Raudvatnet
Just after Mosgruva, Raudvatnet appears on the southern side of the road and Raudfjellet on the
northern side. The rusty weathering colour of the bedrock is the reason for these names
(raud=red). The circular form of Raudvatnet has given rise to speculations as to whether it was
formed by meteoritic impact. So far no proof of this has been found.
Part of the bedrock map Storforshei, scale 1:50,000. Mosgruva lies in the upper left corner of the
map, northwest of Raudvatnet.
142 Locality 65 - Storakersvatnet
The road continues south and southeastwards through amphibolites, gneisses and micaschists.
The highest point on the road, about 650 m, is at Umskaret. A narrow gravel road branches off to
the south here and leads to an area with beautiful mountain scenery. The road is 47 km long and
was built in connection with regulation of the drainage system. Along the north side of
Storakersvatnet it passes through limestone terrain where both grey-blue calcitic marble and
yellow-white dolomitic marble are present. In the dolomitic marble crystals of white tremolite
10-15 cm long can be found. It is probably possible to find other calc-silicate minerals such as
diopside. It is especially easy to find minerals by the lake when the water level is lowered. The
height of adjustment/regulation is 43 m.
The road continues via Akervassdammen southwards along the west side of Storakersvatnet,
passing by Kjennsvatnet and finishing at the dam at the west end of Grasvatnet. The road is
143 narrow and often badly maintained. At Kjennsvatnet there is an unmanned tourist hut called
Kjennvasshytta. This is very convenient as a departure point for hiking in the Okstind area. (Keys
to the hut can be obtained from the tourist office in Mo i Rana or in Korgen).
The highest mountain in north Norway, Oksskolten (1,916 m), and Nordland's third largest
glacier, Okstindbreen, are found here. (NB! It is not recommended to walk around on the glacier
without a qualified guide! The local hill walking association arranges walks on the glacier during
the summer). The bedrock in Okstindan is not so very well studied. Most of the area around the
glacier and the highest summits consist of garnet and quartz-rich mica-schists. They are the same
rocks as those at the dam at Grasvatnet.
144 Locality 66 - Ice-polished rock surface at Umbukta mountain lodge
North of the lodge (250 m) we find rocks from the same zone seen in the area at Storlia in
Dunderlandsdalen. A garnet-bearing micaceous gneiss cut by dark amphibolite dykes and white
tonalitic veins and lenses characterizes the area. The youngest rock here is a white pegmatite vein
consisting of quartz and feldspar, and which can be seen close to the road. It has sent thin white
veinlets into the amphibolite, and these are therefore the youngest.
The rocks are strongly deformed and folded and also cut by several steep faults oriented about
north-south. Faults are joint surfaces along which there has been some movement. On one side of
the joint the rock is displaced in relation to the opposite side. Here it is only a question of small
movements from a few centimetres to a few decimetres. On some of the fault planes there has
been some mineral growth since movement took place. One can also find thin, black, stretched
slivers of biotite.
145 146 Locality 67 - National border (Norway -Sweden)
From Umbukta mountain lodge to the border there are a number of road-cuts in gabbro. This is a
dark rock which originates as a melt or magma and which forces its way up from depth and
solidifies. It is normally an excellent rock for road construction since it is durable and suitable as
aggregate for road surfacing. From the border and 300 m inside Norway there are several
exposures of gabbro which are cut by a light-coloured rock. This rock has the appearance of an
intrusive breccia with dark fragments of gabbro in a lightcoloured matrix. It is possible to find
joints filled with yellowish brown carbonate minerals, black biotite and gold-shimmering pyrite
in the gabbro.
147 Is it growing?
The glaciers of today give us an immediate feeling of closeness to the past and to a colder
climate.
The part of geological history nearest to us in time is the Quaternary. It covers the last 2-3 million
years and includes several ice-ages and relatively rapid climatic variations without any form of
human interference.
Part of the key to predicting our future climate lies in an understanding of the ice-ages and the
natural climatic variations which have taken place over the last hundreds of thousands of years.
As is evident from the chapter on glaciations in this book Nature follows its own rules as regards
climate. So far natural processes have exercised complete control on the amount of ice on our
planet. There are now clear signs that we are between two ice-ages and that in the distant future
the country will once again be enveloped in ice as long as Nature alone determines the climatic
conditions. But today human pollution and the greenhouse effect threaten to disturb the delicate
balances in Nature. To what extent the human entry Into the arena will change the natural course
of climatic events remains to be seen. But one can justifiably question the behavior of the glaciers
in the future and, like the tourist in the picture with a distant view of Svartisen, ask oneself: Is it
growing? -or shrinking?
148 Mines and quarries in the Arctic Circle area
Altermark
The Altermark talc mine lies west of Mo i Rana on the north side of Ranafjorden, Rana
municipality. The mine was started in 1932 and is still in operation. The mineral talc is removed
from a soapstone and used today as filler in paint, stopper, plastics and paper.
Bertelsberget
Silver-bearing galena deposit which lies just southeast of Mo i Rana, the Rana municipality. The
occurrence was found and production started in the latter half of the 17th century. There is a
signposted road and path to the mine.
Brenne
A marble quarry in Saltdalen, 7-8 km south of Rognan, Saltdal municipality. A colourful
calciferous banded marble in shades of red, yellow and blue is worked here. The marble is
schistose and splits easily. It is used in the first instance for headstones and floor tiles.
Båsmoen
A pyrite mine at Båsmoen just northwest of Mo i Rana, Rana municipality. The period of
operation extended from 1894 to 1937 with a few pauses. In all about 15 million tons of pyrite
ore were mined.
Ertenvågen
A dolomite quarry on state highway 17 in Gildeskål municipality. This dolomite is white,
medium grained and of sedimentary origin. It has a number of uses, for example, as an additive in
149 metallurgical processes, in glass production, and as a filler in paint and plastics. It is also used in
the manufacture of magnesium oxide and magnesium metal and also for soil improvement.
Evja
A granite quarry in Beiarn municipality. This is a light-coloured granite used mostly for
tombstones and sculptures as, for example, for the sculptures at the Arctic Circle Centre,
Saltfjellet.
Ljøsnehammaren
A marble quarry at Ljøsnehammaren on the road between Saltdal and Beiarn, Skjerstad
municipality. A colourful calciferous marble with pink, yellow and white bands is found here.
Malmhaugen
Pyrite mine in Plurdalen east of Mo i Rana, Rana municipality. The occurrence was test-mined by
Båsmoen Gruber in the period 1915-1923 and 5,000-6,000 tons of pyrite taken out.
Misvær
Old granite quarry in Misvær, Skjerstad municipality. White granite was mined here and used
mainly for tombstones.
Mofjellet
A zinc/lead mine on the southern boundary of Mo i Rana, Rana municipality. The occurrence was
found in 1688 and the first attempt at mining carried out in the second half of the 19th century.
The mine was closed in 1987 when the ore reserves were exhausted. " Zinc, lead and copper were
produced.
150 Mosgruva
The pyrite mine northwest of Raudvatnet, 1 km from the highway E12, Rana municipality. The
mine was worked for pyrite in the period 1911-1919. About 53,000 tons of pyrite were mined.
The mine openings are now closed.
Mårnes
A quartzite quarry on Sandhornøy, Gildeskål municipality. Quartzite is mined here and shipped
to Salten Verk in Sørfold where it is used in the production of ferrosilicon.
Nasa
A lead/silver/zinc mine on Nasafjell, Sweden. Silver-bearing galena and zinc blende were mined
here from 1635 to 1659 and from 1770 to 1810.
Oterstrand and Kattvassfjell
The molybdenum mines at Laksådalsvatnet, Gildeskål municipality. Molybdenum sulphide was
mined here from 1918 to 1920 and from 1937 to 1945. About 260 tons of molybdenum
concentrate was produced. Molybdenum is used in steel alloys, electric light bulbs and in the
electronics industry.
Rana gruber
The iron ore deposits in Dunderlandsdalen, Rana municipality. The deposits are mined by open
pit methods and production has taken place in several periods between 1904 and the present day.
Over 70 millions tons have been mined. Iron has many uses in our society.
151 Rendalsvik
Mica and graphite mines.on the south side of Holandsfjorden, Meløy municipality. The mica
mine was operated in the period 1970-1980 for white mica from a mica-schist. The graphite mine
was in production before and during World War II.
Stolplia
Soapstone quarry in Misvær, Skjerstad municipality. Soapstone is a very soft rock, easy to work.
It has therefore been used from time immemorial for the manufacture of articles in i every day
use such as weights for fishing nets, bowls, ovens etc. It has also been used as building stone,
particularly In our old stone churches. Today, talc is the most Important product from this rock in
Norway, but attempts to restart production from this deposit have foundered on conservation
regulations.
Storvika
Marble quarry in Storvika, Skjerstad municipality. A conglomeratic marble with white dolomite
pebbles in reddish calcite is found here.
Øyjord
Limestone quarry northwest of Mo i Rana, Rana municipality. The quarry supplied limestone to
Norsk Jernverk from 1953 to 1977 for the production of iron. 2,600,000 tons were used.
152 Solvågtind in Junkerdalen with its characteristic peak in late evening sun. Photo: Terje H.
Bargel.
153