Jökull - 01.06.2000, Síða 73

Páll Einarsson and Bryndís Brandsdóttir
getur valdið margra metra hækkun á grunnvatni. Hlut-
fallið fer þó eftir því hversu vel bræðsluvatnið skilar
sér niður í grunnvatnið, poruhluta bergsins og fleiri
atriðum. Poruþrýstingur í berginu vex því að líkind-
um mun meira heldur en sem nemur lækkun norm-
alspennu á misgengisflötum, en báðir þættir eru jafn-
gildir til lækkunar á núningi.
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72 JÖKULL No. 49