Jökull - 01.12.1988, Blaðsíða 31

ridges of low relief, and diversified by numerous
small proglacial lakes. Successively older outwash
deposits at Skaftafellsjökull are generally preserved
intact as discrete units, separated by almost continu-
ous bands of moraine. Kettle-hole lakes are
developed in places as a result of supraglacial
outwash deposition during periods of particularly
rapid retreat.
At Svínafellsjökull, by contrast, the more gradual
and somewhat erratic recession of the ice-front has
produced a more complex series of much higher
moraines, by repeated ’bulldozing’ of sediment
released by ablation at the glacier snout. Ice-
marginal lakes are present at Svínafellsjökull,
enclosed by the high moraines, but kettle holes are
generally absent. Outwash deposits at Svínafells-
jökull are almost entirely developed outside the ter-
minal moraines, where they are preserved as a series
of dissected terraces, flanking the modem courses of
the major outwash streams.
These two distinctive assemblages of landforms
and deposits can be recognized as elements of
different glacial landsystems (Boulton and Paul,
1976, Boulton and Eyles, 1979, Eyles, 1983b). the
features at Svínafellsjökull are characteristic of the
glaciated valley landsystem, as would be expected
for a glacier of this type, whilst those at Skaftafells-
jökull bear a closer resemblance to the
subglacial/proglacial landsystem, reflecting the tran-
sitional form of Skaftafellsjökull as a piedmont
outlet glacier, with a relatively limited supply of
englacial and supraglacial debris.
ACKNOWLEDGEMENTS
Fieldwork was undertaken on the 1984 Liverpool
Polytechnic Iceland Expedition, with financial sup-
port from the British Geomorphological Research
Group and the Liverpool Geological Society.
Thanks are due to the Icelandic National Research
Council for permission to work in Iceland; to Amold
Jones, Chris Hall and Chris Hunt for field assistance;
and to Amold Jones and two anonymous referees for
helpful comments on an earlier draft of the
manuscript.
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JÖKULL, No. 38, 1988 29