CERI was invited by the Cascades Volcano Observatory (CVO) and the Pacific Northwest Seismograph Network (PNSN) to assist in the seismic monitoring effort of Mount St. Helens (MSH). The purpose of the mission is to augment the permanent network with high quality portable broadband and strongmotion instrumention to collect perishable data that can be used for future research to improve our understanding of volcanic hazards and to provide data for more immediate assessments of the hazard.
From Thomas Brackman's journal, 3 Oct 2004:
October 2, 2004. The field team departed Memphis at 6:40 Saturday morning October 2 and arrived that afternoon. They secured a vehicle, lodging, batteries, and other equipment Saturday afternoon and will be meeting with CVO and PNSN personnel at 10PM CDT to develop a plan to install four stations on Sunday. Additional equipment was delivered to the FedEx heavy weight facility in Memphis on Friday afternoon and will be available on Monday 10/4. The field team will then continue to expand and harden the network.
October 3, 2004. Four broadband stations were installed today. Traffic and relatively large crowds tended to be a hindrance. Law enforcement was generally cooperative in granting brief access to restricted areas for siting and installation.
October 4, 2004. One station was moved to a quieter location. There are now 5 broadband stations with strongmotion instruments co-located at 2 of them. The original 4 stations have been hardened. Two strongmotion and one broadband remain to be installed. We anticipate that the remaining installations will be completed later today or tomorrow. Plans to install a south flank station close to the crater by helicopter have been put on hold for the time being due to safety concerns.
October 5, 2004. A nice little network has now been deployed around Mount St. Helens. The crew has installed 5 BB seismometers and 3 K2s. They will be looking for one more BB site to close the gap west of the mountain, but it is not required. The same goes for the remaining K2. They are now entering the maintenance stage of the deployment.
October 6, 2004. Journal entry for this day
October 7, 2004. Journal entry for this day
October 8, 2004. Journal entry for this day
October 10, 2004. Journal entry for this day
|Background information on Mount St. Helens.|