The eruption site was seen clearly during yesterday's overflight.
Eruptive activity in the northern ice cauldron remains similar to conditions during the preceding four days. A volcanic crater has formed in the south-western corner of the cauldron. Erupted material from the vent continues to accumulate on the flanks of the crater. The rim of the volcanic crater is ~50 m lower than the surrounding ice cauldron. Volcanic spatter was observed from the vent, with ejected lava reaching heights of 100-200 m.
Unstable plumes of ash rise regularly from the vent.
Lava continues to flow to the north under the ice cap, advancing ~1 km from the crater. Depressions in the ice-surface have formed due to lava being in contact with ice; these features have enlarged considerably since 24 April. The surface of Gígjökull is grey due to ash deposition; likewise, the north-western flank of Eyjafjallajökull is black in appearance.
Booming sounds were reported yesterday from Hvolsvöllur, 32 km west of the eruption site.
The above is based on status report issued collectively by IMO and the Institute of Earth Sciences.
An update on events and prospects, including ash forecasts as well as earlier information, can still be found through links in red at IMO's front page. Check also "Forecaster's remark" (to the right), if relevant. For earlier news of both eruptions, click 2010.
Eyjafjallajökull eruption plume heading westnorthwest from the eruption site, 27 April 2010 at 12:00 GMT. A sharp line is obvious on the ice cap between new snow and even never ash fall. See also larger version; photo: Sigrún Hreinsdóttir.