September 30, 2004

Mount St. Helens - Alert Level Two

From the The Pacific Northwest Seismograph Network: Increased seismicity overnight prompted raising the alert level to Volcano Advisory (Alert Level 2) at 10:40 A.M., PDT, this morning. Throughout the day the seismic energy level has remained at an elevated with a rate of 3-4 events per minute including an increase in the number of events between Magnitude 2 and 3. All earthquake locations are still shallow and in or below the lava dome. In addition, initial data from the GPS instrument on the lava dome that was repaired Monday morning suggest that the site moved a few inches northward Monday and Tuesday, but has since been stable. Such movement is not surprising in light of the high seismicity levels. A USGS field crew continued their deployment of GPS equipment today in order to monitor any ground movement on the lava dome, crater floor, or lower slopes of the volcano. Another gas flight this morning produced a result of no significant volcanic gas detected, as was the case on Monday. Two press conferences were held at CVO to update the media. Tomorrow's field work includes continued GPS deployments. The weather is much clearer today so the VolcanoCam is worth checking out. Stand back boys, she's a-gonna blow! Posted by DaveH at September 30, 2004 12:26 PM