Geografisk Tidsskrift, Bind 52 (1952 - 1953)The Strand Flat of Spitsbergen.W. Werenskiold. Side 302
An almost level plain stretches along the west coast of West Spitsbergen, from South Cape (Sørkapp) to well north of Cross Bay (Krossfjorden), with varying breadth, from 200 m to 10 km. The same flat rim continues along the shores of the fiords, more or less well developed. I have visited these parts several times during the summers of 1917, 1918, 1919, 1923, working as geologist and topographer — living in tents, rowing in small boats from place to place. There are no harbours on the outer coast — only rocks and small skerries; the problem is to get on shore and off shore through the surf. All went well, however. In 1919 (Dr) Orvin and I made a preliminary survey of the district between Horn Sound and Bell Sound, which was practically unknown. Next year I worked in the same area as topographer; but not till now (1952) has the topographical map been finished, in a scale of 1:50000, based on aerial photos. In 1919 I partook in the investigations of the land to the south of Horn Sound. I shall here make
some remarks on the strand flat to the south The strand flat
is well developed along the coasts of the South A great glacier
(Olsok-bre) enters the sea about half way between
Farther to the
north the strand flat extends in varying breadth Side 303
belonging to
the Hecla Hoek system (cambrium), and farther Several faults
cut through the plain, but these have no direct
To the north of Horn Sound, there is first an area of hard metamorphic rocks, amphibolites and gneisses, with a narrow coastal plain, for a distance of about 10 km. Then follows an inaccessible stretch, low muddy flats with many shifting streams, issuing from the margin of the great S. Torell Glacier, a kind of "Malaspina" typus. The glacier enters the sea with a vertical cliff, 40—50 m high, for a distance of 6 km. Then follows a flat, wet delta between the two glaciers, about 3 km; farther to the north west the ice cliff of North Torell Glacier stretches for a new distance of 6 km. Outside this coast, the sea is very shallow, with muddy flats and banks. A group of small islands, Down Islands (Dunøyane), lie off the southern part of the coast, and the Ice Islands (Isøyane) just off Side 304
the above
mentioned delta between the two Torell glaciers. These
To the north of
Torell Glacier follow the broader strand flat, 2 to
I shall now give
a more detailed account of these strand flats,
The strand flat is to a great extent covered with shingle and gravel, that form a great many raised beaches; but the rock is peeping through the cover at many places. The platform has been abraded in solid rock. The coast-line shows many bays and capes. The capes generally consist of hard quartzitic rocks, the smaller or broader bays have been formed on layers of softer rocks, all belonging to the Hecla Hoek series. Low ridges of
quartzite run across the plain, following the strike
Side 305
capes, and they
continue in long rows of rocks and skerries. At the
The sea off the
coast is shallow for a great distance, with many
Behind the bays
lagoons are generally found, separated from the above sea level
and have fresh water, as a result of a recent relative
The plain is
dotted with shallow lakes; brooks and rivers often
The strand flat rises from 8 m to a height of about 20 m. It shows no vestiges of ice erosion, except at the outermost promontories — at Cape Klaveness we (A. Hoel and I) found typical glaciated rocks, striae etc. on the quartzite. The strand flat has obviously been glaciated some time, but the action of the sea has obliterated all signs of glaciation, except those mentioned. Side 306
The strand flat is bordered by a mountain ridge, a wall rising to heigths of about 600 m; but the ridge is cut through by several valleys, that offer passages to the inland ice behind; and from this extensive ice field separate tongues lead down into the back ground of all these valleys. The valleys are all
to a certain degree "hanging" in relation to the strand flat. The rivers have cut down narrow gorges through the steps that lead from the flat valley floors down to the costal plain. In the southermost valley, (Brevassdalen) there is still a lake, 97 m above sea level. In the next valley (Turrvassdalen, meaning Dry Lake Valley) a lake has been drained by the dowrncuttingn- of the outlet; the flat former lake bottom is absolutely bare, with steep beaches, showing that the draining has been quite recent. These facts
show that the strand flat has been formed before Side 307
on abraded into
the foot of the hills, along the inner border, so
To the south of
Horn Sound, the structure of the strand flat First, there is a iteep cliff, 8 m high; a flat plain, 450 m broad, rises gradually to a height of 20 m above sea level. Then comes a steep slope with typical abrasion forms, precipitous headlands and narrow7 clefts, leading up to another plain, which rises from 80 m above sea level, at the outer rim, to 120 m along the inner border. This plain is 700 m broad, and not so flat as the lowermost. It is spread with rounded boulders of red sandstone — the rock below is limestone. The next step
leads up to a ledge, 300 m broad, 185 m above sea
The next ledge
is situated in the great height of 331 to 334 m; Side 308
a fine beach
ridge. Strand shingle is found to a height of 338 m,
Round the southern foot of South Cape Mt (Sørkappfjeilet) a fine plattform has been abraded; the outer edge is about 80 m, the inner border 130 m above sea level. The elevated cliff shows grandiose abrasion features. On the SE slope
of Mt. Dummer Kerl (Russian map; Dumskolten, heights of 210
and 340 m. The rock is here soft tertiary shale, but
These beaches and
strand-lines are all situated on the outer Beaches in very
high levels have been observed in Franz Josef 1) It may be mentioned that in 1919 I discovered some luke-warm springs at the coast of Storm Bay, below Mt. Hilmar. The water discharge of the largest spring — at little lake —- is about 150 litres per second, and the temperature 10° C. (50° F.). The water is salt, and bubbling with sulphuretted hydrogen. Some smaller springs in the neighbourhood are warmer, 15° C. (60° F.) and even more stinking. Side 309
A peculiar
phenomenon may be mentioned here. Just to the north of the mouth of Horn Sound the strand flat is very narrow, on the hard metamorphic rocks. The flat is bounded by a ridge of steep hills, rising like a wall, up to heights of 663 and 637 m, and much dissected by corries (see fig. 3). At the inner border of the strand flat, just below the highest and steepest hill-sides, great heaps of rocks and boulders are found, projecting like bastions, with steep fronts and rather even surfaces — appearing like something between a talus and a moraine; and in fact, they have been formed in a corresponding way. In a rather recent period with somewhat colder climate, steep, isolated snow^patches have accumulated below the highest and steepest mountain walls, at the inner border of the strand flat. In the climate of West Spitsbergen, the weathering and frost-splitting of the rocks is intense, and talus slopes are formed all along the hill-sides. In our case, however, the talus has slid down upon the surface of the snow-patch, forming a rim of stones around the lower end. The inside of the rim was gradually filled up, as the snow field became smaller; at last it melted off, leaving the boulders in a heap, resembling something between a talus and a moraine. Similar
accumulations may be found below steep mountain walls
LIST OF REFERENCESWerenskiold, W.:
Spitsbergens fysiske geografi. — Naturen, Bergen, 1920.
Werenskiold,
W.: Høie strandlinjer på Spitsbergen. — Norsk geologisk
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