This increase in earthquake activity suggest that more magma is pushing up the volcano at faster rate. The main idea now is that the magma that is pushing up Öræfajökull volcano is rhyolite in nature and that seems to be confirmed to an extent by the earthquake activity as it now appearing.
How this develops is a big question due to lack of accurate historical accounts. What is known about the eruption in 1362 was written down up to two centuries later and when that happens lack of accuracy is passed into the written record. The written record for the eruption in 1727 – 1728 is slightly better but is far from being accurate.
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