Jökull - 31.12.2001, Page 13

Geomorphology of Ódáðahraun
Figure 6. Al: A false colour three-band composite image (RGB 541) of the SW-NE oriented (effective wind
direction) aeolian sand stretch between Fremrinámar and Búrfell, seen in dark blue. Vegetation is shown in
pale green. The lavas (e.g. Nýjahraun) from the 1875 fissure eruption are visible as a slightly paler N-S stripe.
A2: A classified image of the same area as in Al. The sand stretch falls mainly in classes b3 and b4 (cf.
Figure 3), surrounded by various lava types (classes a3, a4 and a5). Bl: A false colour three-band composite
image (RGB 541) of the Möðrudalur settlement and the surroundings (cf. Figure 1). The dark coloured area
in the middle is a vast flood deposited delta fan (Grjót), formed when high momentum flood-water escaped the
Jökulsá á Fjöllum course (running from bottom to top, in blue) at the river bend. Vegetation is shown in pale
green. B2: A classified image of the same area as in Bl. The flood plain is mainly in classes b4 and b5 (cf.
Figure 3). The Fjallgarðar hyaloclastite ridge, shown in pale blue and running towards the NNE, represents
class cl. The striping of the original data (TM sensor problem) causes some classification errors, seen as weak
WNW-ESE bands on the image. - Stœkkaðar myndir affoksandsgeirum á milli Fremrináma og Búrfells (A) og
á Möðrudalssvæðinu (B). Myndirnar til hœgri eru lithreyttar (RGB541) þannig að landslag kemur hetur í Ijós
og gróður er grœnleitur. Greina má Bláfjall ofan við A1 merkið og norðaustan þess gróðurlendi í Heilagsdal,
síðan Heilagsdalsfjall og Búrfell. Einnig sést Hverfjall efst til vistri og norðurendi Hvammsfjalla í suðurjaðri
myndarinnar. Auk Jökulsár á Fjöllum, má vel greina árnar sem renna um Möðrudal á mynd B1. Grœna svœðið
austan Lóns, Krókár og Hvannár er Framlandið.
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