Frische Lava scheint sich nun tatsächlich an der bis zu 700°C heissen Oberfläche des Doms zu befinden. Das im obigen Bild sichtbare Glühen war also doch nicht ein Hirngespinst meinerseits
. Das Wachstum des Doms ist auch weiterhin gross. Erdbebenaktivität eher niedrig.
Mount St. Helens Update, October 13, 2004, 6:00 p.m, PDT
Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE
Seismic activity remained at a low level today, maintaining the slight increase that occurred last night. This morning’s visual observations and thermal imaging of the crater were focused on the intensely deforming and uplifting area on the south side of the 1980-86 lava dome and the new lobe of lava in the western part of that area. The area of both the uplift and the new lobe of lava have increased slightly since yesterday. Temperatures of almost 700 degrees C were measured in parts of the new lobe, from which ash-rich jets rose tens of meters. Abundant steam continued to rise from the area of lava extrusion to the crater rim, from which it was dispersed southwestward by strong winds.
Other field work today included a gas-sensing flight (data not yet reduced), downloading GPS data, and observations of water flows and temperatures in streams draining the crater.
Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), combined with eruption models, show variable wind directions tonight, but generally northerly. Any ash clouds will drift southward this evening and southeastward tomorrow morning.
Magma continues to be at a very shallow level and is extruding onto the surface and forming a new lobe of the lava dome. Incandescence or glow from the hot rock will likely be visible intermittently from north of the volcano, or possibly from other vantage points if the right cloud conditions exist.
Lava-dome growth is a dynamic process and, as we observed in the mid-1980s, Mount St. Helens and similar volcanoes elsewhere typically go through episodic changes in level of activity over periods of days to weeks, or even months. Such changes are in part driven by variations in the rate of magma movement. We expect fluctuations in the level of eruptive activity to continue. Escalation could occur suddenly or with very little warning. Therefore, we continue to monitor the situation closely and will issue additional updates and changes in alert level as warranted.
http://vulcan.wr.usgs.gov/Volcanoes/Cas ... dates.html
