There is an increasing amount of magma collecting just northwest of Mt Þorbjörn in Reykjanes, RÚV reports.
Scientists monitoring the area are seeing a rising ground surface and recording thousands of earthquakes over the past week. They say that there is now an increasing likelihood of a quake of a magnitude up to 6.5.
The surface has already raised an astonishing 3.5cm over the past few days, and magma is collecting about four kilometres beneath the surface between Mt Þorbjörn and Eldvörp, an area noted for its rows of lava craters created in the 13th century.
There have been some 3,800 earthquakes in this region over the past week, the largest being a 4.8 last Saturday and a 4.3 the following day.
As always, volcanic eruptions are notoriously difficult to predict, so while an eruption is possible, the exact certainty is still unknown.
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