Jökull - 01.12.1985, Page 26

Little Ice Age glaciation on Hornstrandir quite usable in
this context (Thoroddsen 1906, 1911), but according to
Eythórsson (1935), Thórarinsson (1943) and John
(1977b) the oldest moraines in front of some of the
outlet glaciers from the nearby Drangajökull (25 km
southeast of Fannarlág) date from the middle of the
18th century, in front of others from 1840—1850. This
agrees reasonably well with our tentative dating of the
outermost Fannarlág moraines to 1860 or older.
The M5 value of about 28 mm at point 0 indicates that
some time has passed since the glacier disappeared. If a
colonization time of at least 5 years is used and a growth
rate of 0.5 mm/yr, a deglaciation date around 1920 is
reached.
PRESENT GLACIATION
Today only four cirques within the studied area of
Hornstrandir contain glaciers. Three of these lie inside
Hornvík, with their floors around the 500 m level, and
one inside Hlöduvík with its floor around the 300 m
level (Fig. 13). The Hlöduvík glacier is exceptional,
100-
Fig. 15. Lichenometry of the Fannarlág cirque inside
Haelavík (Figs. 7 and 14). The measurements were
made on moraines and other surfaces uncovered since
the Little Ice Age (points 0-8, ending by the arrow),
and at two sites outside the area glaciated during the
Little Ice Age (points 9 and 10). For each point the
mean for the five largest thalli (M5) of Rhizocarpon
geographicum agg. and Rh. afpicola, and the size inter-
val covered by them, is shown. The sloping dashed line
illustrates what kind of pattern would be expected if the
glacier retreat had been constant. 15. mynd. Fléttumœl-
ing fyrir Fannarlág. Fléttur voru mældar á jökulgörðum
og öðrum flötum sem voru undir ís á Litlu Isöld. Til
viðmiðunar var einnig mœlt á tveim stöðum sem voru
íslausir þá (punktar 9 og 10). Skyggða beltið sýnir niður-
stöður mælinganna, en hallandi brotalína sýnir hvaða
mynstur jafnhröð hopun jökulsins hefði orsakað.
Fig. 14. Little Ice Age moraines in the Fannarlág cirque
inside Haelavík. Photo 18/7 1983. 14. mynd. Jökulgarð-
ar frá Litlu Isöld í Fannarlág í Hœlavík.
since several higher situated cirques.in its neighbour-
hood are unglaciated. In all, the total area of the four
cirque glaciers on northern Hornstrandir today is only
1.0—1.5 km2. To this come an undefined number of
small ice-cored perennial snowdrifts and firns at
various, mostly high, altitudes. The cirques containing
ice today contained much larger (Hlöduvík) or sorne-
what larger (Hornvík) glaciers during the Little Ice Age
(Fig. 13).
The present ELA for cirques on northernmost Horn-
strandir lies around or slightly above 500 m. The general
glaciation limit lies above 600 m. This should be com-
pared with an ELA, in an open position, at 700—800 m
on Drangajökull (Th. Einarsson 1968).
LATE FLANDRIAN TRANSGRESSION
Today’s sea level on Hornstrandir has risen in com-
parison with earlier parts of the Flandrian. This is
indicated by the coastal erosion of the low level fluvial/
lacustrine sediments in Haelavík — with simultaneous
deposition of very coarse beach material onto parts of
the cliff face. Distinct erosional cuts in the fronts of
talus cones, especially below Kögur north of Fljótavík
(Fig. 16) probably also indicate a presently rising sea
level.
SUMMARY AND DISCUSSION
(1) During the last (Weichselian) glaciation the Vest-
firdir peninsula was probably covered by an indepen-
dent ice cap (Thoroddsen 1906, Thórarinsson 1937, Th.
Einarsson 1968, John 1977a, Sigurvinsson 1983). The
24 JÖKULL 35. ÁR