On the northern side a tephra wall rises 20 meters above the water. The ice walls at the southwestern corner of the crater are melting, i.e. at the site of the vent that was active 4 - 6 June. The rate of melting is assumed to be about one cubic
meter per second.
Details on the volume of the lake, and possible flooding from it, in a status report issued collectively by the Icelandic Meteorological
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