Images

This summer, crews made significant modifications to a monitoring station on the southwest flank of Mount St. Helens, greatly improving its operability in winter.

Crews survey Loowit Creek channel and other points inside the crater. Elevation information is used to make a longitudinal profile of the channel, characterizing areas where sediment is either deposited or transported and how the channel is changing with time. View to the north, with Spirit Lake and Mount Rainier in the background.

A survey base station is established using a RTK-GPS receiver with mobile units to collect data points in and around the crater. Information will be used to monitor surface changes, deformation, erosion and aggradation inside the crater. This type of technology is precise to the centimeter. View is to the south of Mount St.

Fieldwork includes direct observations of changes to streams and stream beds to determine how changes will affect the downstream transportation of sediments. Here, the braided North Fork Toutle (left) joins Carbonate Springs Creek (right). View to the east.

Monitoring and upgrading ground-based sensor networks at the most active volcano in the Cascades is an on-going process. Crews made significant modifications to a seismic monitoring station on the southwest flank of Mount St. Helens, greatly improving its operability in winter.

Monitoring stations need to be portable. Weighing about 500 pounds, this "swing set" structure can be airlifted into place or moved, as volcano monitoring needs change. An additional 1,000 pounds of equipment will need to be added to make the station fully functional.

Crews access remote monitoring sites by helicopter. Pictured out the window of the helicopter is a GPS and camera station, dedicated to remotely monitoring changes inside the crater and under the crater floor.

A survey base station is established using a RTK-GPS receiver with mobile units to collect data points in and around the crater. Information will be used to monitor surface changes, deformation, erosion and aggradation inside the crater. This type of technology is precise to the centimeter. View to the south, toward Crater Glacier and the lava domes.

Crater Glacier, located inside the crater of Mount St. Helens, continues to move at an average rate of about 11 cm per day (4.3 inches). During warm weather months, meltwater creates erosional channels on the crater floor.

In summer, the crater of Mount St. Helens is filled with a near constant sound of rockfall from the steep 600 m high (about 2000 feet) crater walls. The falling rock kicks up ash and dust (pulverized rock) as it tumbles onto the crater floor. View of east crater wall.

Steaming continues on the 1980-1986 dome. View to the south and the east arm of Crater Glacier.

A fumerole near the 1980-86 dome keeps an open hole in the east arm of Crater Glacier. The hole is approximately 12 m (40 ft) in diameter, easily wide enough to hold a school bus and deep enough so you could not see the bus' top. View to the south.

Center for the Study of Active Volcanoes (CSAV) students Javier Pacheco (Costa Rica) and Syegi Kunrat (Indonesia) participate in field studies at Mount St. Helens.

Teachers take a guided walk on the Hummocks Trail, learning about the depositional features of the May 18, 1980 eruption.

Todd Cullings, with the Mount St. Helens National Volcanic Monument, leads teachers in activities they can do with students before hiking the Hummocks Trail.

The September Lobe monitoring station is part of the network of monitoring stations that detects and reports subtle changes in the volcanic vent area. At 2150 m (about 7100 ft) elevation, maintenance is performed during good weather to keep the station fully functional.

To monitor volcanoes, scientists rely on remote monitoring equipment that can operate 24-hours a day and 365-days a year to deliver real-time data. When scientists design and install monitoring stations, they must consider the remoteness of sites, terrain, and winter conditions. Here, rime ice coats a telemetry system that transmits data near Mount St.

Lakes and drainages within the watershed of Mount St. Helens.

The east face of Middle Sister is 350 m (1150 ft) high. Ice-sculpted pile of lavas at right, variously called "Black Hump," "Prouty Point," or "Step Sister," has 190 m of relief and consists of at least five flows.

Mount St. Helens and the industrial waterfront area of North Portland, Oregon along the Willamette River in the foreground. Excess sediment from volcanoes can significantly impact river traffic.

Logs float in Spirit Lake near the Spirit Lake gaging station and outflow tunnel. View is to the south with Mount St. Helens in the background.