Rit (Vísindafélag Íslendinga) - 01.07.1931, Page 16

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Fig. 6. The eastern side of Snæfellsjökull with Þríhyrn-
ingar and the middle-peak. X is the place of a fixing mark.
(Photo J. Ey. ls/7 1930).
N = 10 km. — It is curious that the snowfield, as shown
on the map, is fairly congruent with the shore-line that
surrounds it.1)
The mountain itself is a young volcano although no erup-
tion from it has taken place in the historical time of Iceland,
i. e. for the last 1000 years. The chief crater opens to NW
and three sharp peaks rise above the south- and east-edge
of the cratercirque, the middle one reaching the height of
1446 m. above sea level. The volcano consists for a great
deal of tuff with basalí or dolerit intrusions in places. On
the east slope curiously formed, about 1200 m. high, nuna-
tacks called Þríhyrningar (the Threepeaks) rise out of the
firn. They are mostly built up of red slack and dark pumice
(Icel.: vikur) and seem to be the rest of an old eruption-
place.
The very steep southern side of the volcano is interwoven
with lava-streams, that show no signs of denudation up to
the last 50 m. below the edge of the firnfield, which in this
place reaches its greatest height, about 1070 m. With the
exception of the northern side the glacier is surrounded by
1) Topographical map No. 5 Snæfellsjökull NA.
j