Jökull - 01.01.2013, Page 67

Surface deterioration of glacially abraded basaltic boulders by Fláajökull
ÁGRIP
Fláajökull hefur hopað meira en 1500 m frá lokum 19.
aldar. Mælingar á þykkt veðrunarkápu, höggendur-
varpi og hrjúfleika yfirborðs steina ofan á jökulgörð-
um framan við jökulinn gefa til kynna hvenær hann
gekk fram og myndaði garðana.
Niðurstöður sýna að hrjúfleiki yfirborðs og þykkt
veðrunarkápu steina eykst og höggendurvarpsgildi
minnkar með aldri á jökulgörðum sem eru allt að 80
ára gamlir. Teljandi breytingar er ekki að sjá á jökul-
görðum sem eru eldri en 80 ára.
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