Jökull - 01.01.2015, Page 58

J. Schuler et al.,
ÁGRIP
Jarðskjálftavirkni á Þeistareykjasvæðinu var könnuð
með neti færanlegra jarðskjálftamæla á árunum 2009–
2012. Skjálftavirknin var aðallega bundin við vest-
urhluta Bæjarfjalls, í þyrpingu með upptök á 2–5
km dýpi sunnan jarðhitasvæðisins. Dreif af mun
dýpri skjálftum mældust suðaustur af Þeistareykj-
um, á 8–20 km dýpi, í deiga hluta jarðskorpunnar.
Djúpu skjálftarnir liggja á milli sprungusveima Þeista-
reykja og Kröflu, nálægt upptökum Borgarhrauns og
gætu tengst kvikuhreyfingum innan gosbeltisins, en
einnig spennubreytingum innan Húsavíkur-Flateyjar-
brotabeltisins.
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