Jökull - 01.01.2015, Page 26

Sigmarsson and Halldórsson
ÁGRIP
Eldstöðvakerfi eru grunneining í gosbeltum Íslands.
Megineldstöð og sprungurein, eða hvort um sig, geta
talist eldstöðvakerfi. Rekhrinunni 2014 í Bárðar-
bungu-Veiðivatnakerfinu lauk með sprungugosi í
rein sem hefur verið talin til eldstöðvakerfis Öskju.
Samsetning basaltsins sem upp kom er hins vegar
mjög svipuð þeirri sem einkennir Veiðivatnareinina.
Samsætumælingar Sr og Nd í þremur sýnum frá gos-
inu í Holuhrauni gefa sömu hlutföll 87Sr/86Sr og
143Nd/144Nd og mælst hafa í nútíma gosbergi Bárðar-
bungu-Veiðivatnakerfisins. Ólík hlutföll mælast í
hraunum Öskjukerfisins og einnig í Þjórsárhrauni og
tveim gömlum hraunum á jöðrum Veiðivatnareinar-
innar. Ólík samsætuhlutföll í gosefnum aðliggjandi
eldstöðvakerfa koma að notum við að finna hvaðan
goseiningar eru ættaðar, sem er grundvöllur fyrir mati
á gostíðni og kvikuframleiðni hvers eldstöðvarkerfis.
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26 JÖKULL No. 65, 2015