Jökull - 01.01.2016, Blaðsíða 94

Leó Kristjánsson
segulmælingar, valdar bergfræðirannsóknir, og ald-
ursgreiningar á staflanum í Inn-Djúpinu. Í slíku átaki
sem er löngu orðið tímabært, mætti jafnframt m.a.
varpa ljósi á þætti í eðli eldvirkninnar sem myndaði
hina eldri hluta landsins. Að auki getur þekking á
tilvist óstöðugleika-tímabila í sögu jarðsegulsviðsins
nýst við túlkun mælinga á segulmögnun sjávarsetlaga
og á segulsviðs-frávikum yfir úthafshryggjum. Oft
eru gerðar tilraunir til að meta styrk fornsegulsviðs-
ins og auka þannig skilning á hegðun þess, til dæmis
meðan á umsnúningum og öðru meiriháttar flakki seg-
ulskautanna stendur. Eiginleikar bergsins í viðkom-
andi hraunlögum í Ísafjarðardjúpi virðast þó gera það
miður heppilegt til þesskonar tilrauna.
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94 JÖKULL No. 66, 2016