Jökull - 01.01.2012, Page 120

A. Schomacker et al.
Figure 5. Examples of landforms in the forefield of Sólheimajökull. Landforms are visualized as oblique views
of the 2007 aerial ortho-photograph draped over a 5 m DEM. Vertical exaggeration is x2. The thick arrows
indicate the ice-flow direction. – Dæmi um landform við Sólheimajökul. Skámyndir unnar út frá loftmyndum
sem lagðar voru ofan á hæðalíkan með 5 m upplausn. Hæðarýking er tvöföld. Örvarnar tákna skriðstefnu
jökulsins. A: jaðargarðar. B: endagarðar og jökulöldur. C: árgarðar og farvegur eftir jökulhlaupið 1999. D:
jökulhlaupaset og jökuláreyrar. E: minniháttar árkeilur. F: malarás og dauðís.
that unit 3 was deposited within a day or two (Maizels,
1997; Björnsson, 2002).The pumice and the jökul-
hlaup deposits indicate ice free conditions in the area
around section 1. The diamict in unit 5 is interpreted
as subglacial traction till, and consequently indicates
glacial conditions and expansion of Sólheimajökull.
The glacier then retreated from the site to allow the
formation of a small delta in an enclosed, shallow
proglacial lake. This is suggested by units 6–8, which
are interpreted as prodelta, delta front, and delta plain
deposits, respectively. The thickness of the bottom-
sets and foresets shows that the lake was only about
4.5 m deep. Sólheimajökull advanced again across
the site as indicated by the tills in units 9–11. Unit 9 is
thickest of these which could suggest a more sustained
advance while the thinner tills in units 10 and 11 could
indicate small readvances during overall glacier reces-
sion. Alternatively, units 9–11 represent only one till,
which, in that case, would suggest one sustained ad-
vance. Numerous clastic dykes (water escape struc-
tures) cut through most of the section. They originate
from the base of unit 9 and dip towards S-SW (Le
118 JÖKULL No. 62, 2012