The Icelandic Meteorological Office (IMO) reported that a fissure within the Reykjanes volcanic system that began erupting on 16 July in an area NE of Stóra Skógfell, along the Sundhnúkur crater row, continued to erupt during 30 July-4 August. Fountaining activity decreased during this time, but flows continued to spread across the lava field. On 5 August the eruption ended with no activity observed in the crater and volcanic tremor decreasing to pre-eruptive levels. The Aviation Color Code was reduced from Orange to Yellow, reflecting continuing hazards from cooling flows and gas near the lava field. Uplift is continuing at the rate of 2-3 cm beneath Svartsengi as determined by satellite and GNSS measurements.

Geological Summary. The Reykjanes volcanic system at the SW tip of the Reykjanes Peninsula, where the Mid-Atlantic Ridge rises above sea level, comprises a broad area of postglacial basaltic crater rows and small shield volcanoes. The submarine Reykjaneshryggur volcanic system is contiguous with and is considered part of the Reykjanes volcanic system, which is the westernmost of a series of four closely-spaced en-echelon fissure systems that extend diagonally across the Reykjanes Peninsula. Most of the subaerial part of the system (also known as the Reykjanes/Svartsengi volcanic system) is covered by Holocene lavas. Subaerial eruptions have occurred in historical time during the 13th century at several locations on the NE-SW-trending fissure system, and numerous submarine eruptions dating back to the 12th century have been observed during historical time, some of which have formed ephemeral islands. Basaltic rocks of probable Holocene age have been recovered during dredging operations, and tephra deposits from earlier Holocene eruptions are preserved on the nearby Reykjanes Peninsula.

Source: Icelandic Meteorological Office (IMO)