Jökull - 01.12.1990, Side 65

Younger striae show that ice caps were separated
from the inland ice as the deglaciation progressed.
These ice caps were situated on the mountain areas
°f the present glaciers, such as Langjökull and Hofs-
Jökull. The culmination area of the main ice sheet
was gradually shifted towards south as the glacier re-
treated. This migration began after the retreat from
the Búði end moraines which are of Preboreal age.
In the Tungnaá area the ice movement was due
north from the final ice cap on Tungnaárfjöll and
Grænifjallgarður near lake Langisjór. On the other
hand striae found to the south of Grænifjallgarður
point towards SSE. It is clear that ice flow from an
ice divide in this area to the Tungnaá area did not
occur until in the very last stage of the recession.
acknowledgements
We wish to thank the National Energy Authority
and the National Power Company for the permission
to use data collected in connection with geological
mapping on behalf of these companies. We also wish
to thank Freysteinn Sigurðsson, Tómas Jóhannesson,
Halldór G. Pétursson and Hreggviður Norðdahl for
kindly reading the manuscript and Páll Ingólfsson for
correcting the English. We thank our co-workers and
assistants in the field for inspiring discussions through
the years.
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