Jökull - 01.01.2019, Page 24

Terminus lakes on the south side of Vatnajökull
outlet glaciers, which are located at the eastern edge
and to the east of Breiðamerkursandur, are also de-
scribed in this section.
Fellsárjökull and Brókarjökull
According to Guðmundsson (1972), a deep lake was
temporarily formed by the terminus of Fellsárjökull
when the glacier dammed a canyon near its maxi-
mum extent at the end of the LIA. Jökulhlaups from
this lake during the 19th century deposited flood sed-
iments that can still be seen on the Fellsáraurar out-
wash plain. This lake is shown in Figure 19 with an
outline based on the elevation of the outflow threshold
to the south, but the extent of the lake to the north and
the lake area are unknown.
The Brókarjökull glacier resides at the bottom of
the valley Kálfafellsdalur in Suðursveit (Figure 19).
When the mapping of the DGS took place in 1903,
this steep glacer had retreated ∼0.5 km from its outer-
most LIA moraines, formed near the end of the 19th
century. Near its maximum LIA extent, the glacier
dammed up a lake in the valley Vatnsdalur with depth
up to 30 m but the DGS map shows no lake in the
valley in 1903. The highest lake level was at 265 m
a.s.l. and the maximum area > 0.06 km2. During the
Figure 19. The development of terminus lakes by Fellsárjökull (left) and Brókarjökull (right). For explana-
tions and credits see the caption of Figure 3. – Þróun sporðlóna við Brókarjökul and Fellsárjökul (sjá nánari
skýringar við 3. mynd).
JÖKULL No. 69, 2019 23