Mt. Fitzherbert

View taken on 2005-Apr-28

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift east-northeastward at low altitudes, and eastward at higher altitudes.

Recent observations: The Forest Services VolcanoCam shows the volcano currently obscured by clouds. Clouds obscured the view of the crater for the entire evening last night. The volcano remains relatively quiet. Seismicity remains at the recent typical level of one small earthquake (~ M1) every few minutes with smaller events occurring more frequently.

Posted by Raoul Ortega at 17:57 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift east-northeastward at low altitudes, and eastward at higher altitudes.

Recent observations: In response to reports of minor ash fall associated with Wednesday evening's thunderstorms, a crew flew by the volcano yesterday, but found no new ashfall deposits on the volcano. Dust and ash that fell in raindrops constituted fine material entrained by the storms, possibly from fine ash rising from small rockfalls off the dome. The volcano remains in a relatively quiet state, emitting low levels of gas and generating small earthquakes about every 3 to 5 minutes. On a somber note, the CVO staff is saddened by news of the tragic loss of several colleagues from the Philippine Institute of Volcanology and Seismology in a helicopter crash yesterday.

Posted by Raoul Ortega at 10:15 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift south-southeastward early in the day and southeastward later.

Recent observations: Many people in the eastern part of the Portland metropolitan area awoke this morning to slightly grimy windshields. We collected samples of the grime and found that it contains some fine ash. Seismic instruments show no evidence of an explosion occurring and there is no evidence of significant new ash on snow in the crater. We think that the large convective storms that built up over the Cascades (including Mount St. Helens) yesterday afternoon and evening and moved southward were the culprits. The storms entrained ash generated by the frequent hot rockfalls from the growing lava dome and kept it in suspension. Some of the ash we see in eastern Clark County appears to have fallen in raindrops. A crew is on the way to the volcano to get a close look at the dome and crater and to collect some ash samples on the volcano's flank.

Posted by Raoul Ortega at 19:22 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift south-southwestward early in the day, and south to south-southeastward later.

Recent observations: The Forest Service's VolcanoCam shows that the volcano is clear and emitting a diffuse vapor and ash plume from the growing lava dome. Yesterday morning, collapse of a rock column on the dome's northeast face created a photogenic cloud that sent a minor plume of ash rising above the rim. A sequence of before, during, and after photos is posted on the USGS website. Gas measurements yesterday show that the volcano continues to emit very low levels of sulfur dioxide (SO2) and carbon dioxide (CO2), showing that magma driving the eruption remains gas poor. Seismicity remains at the recent typical level of one small earthquake (~ M1) every few minutes with smaller events occurring more frequently.

Posted by Raoul Ortega at 10:27 | Permalink

Views taken on 2005-Apr-26

Some new photos from within the crater.

Posted by Raoul Ortega at 20:17 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift northwestward early in the day. Later in the day, ash clouds would drift southeastward at lower altitudes and northwestward at higher altitudes.

Recent observations: The Forest Service's VolcanoCam shows that the volcano is clear this morning above the low clouds that cover the Portland metropolitan area. A diffuse vapor and ash plume is rising from the growing lava dome. If wind conditions are favorable, scientists will make airborne gas measurements today. Seismicity remains at the recent typical level of one earthquake of about M1 every few minutes with smaller events occurring more frequently.

Posted by Raoul Ortega at 09:58 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift westward to west-northwestward.

Recent observations: The volcano is hidden by clouds this morning, but data from field instruments indicate no significant changes in seismicity or ground deformation overnight. Qualitative analysis of recent photographs suggests that the rate of extrusion at the north end of the new lava dome continues at about 2 to 3 meters (6 to 10 feet) per day. More precise measurements await installation of additional surveying targets on the dome. Good weather is forecast throughout the week, so field crews should be out on several days.

Posted by Raoul Ortega at 10:12 | Permalink

• Popular Mount St. Helens Observatory Set To Reopen 2005-Apr-23 07:32 from KIRO (ch.7) Seattle

  CASTLE ROCK -- Johnston Ridge Observatory overlooking Mount St. Helens is set to reopen for the summer on May 6. The observatory is located at the end of State Route 504, east of the Coldwater Ridge Visitor Center. It has been closed since last October 2.

Posted by Raoul Ortega at 10:20 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift northwestward early and west-northwestward later.

Recent observations: Although it is emitting a moderately strong steam plume this morning, the volcano remains relatively quiet. Small (~M1) earthquakes continue to occur about once every three to five minutes. A rockfall from the dome at about 4:50 a.m. produced a visible flash on the VolcanoCam image. Weather permitting, crews will be in the field in the coming week to measure gas, resurvey targets on the dome, redeploy a GPS unit on the dome, and conduct observation flights.

Posted by Raoul Ortega at 10:17 | Permalink

More views taken on 2005-Apr-21

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift north-northwestward.

Recent observations: The volcano remains relatively quiet today. Small (~M1) earthquakes are occurring about every three to four minutes, and GPS receivers in the crater continue their slow rates of displacement. Analysis of aerial photographs indicates that as of March 10 the topographic changes in the crater resulting from growth of the new dome and consequent glacier deformation have a combined volume of about 62 million cubic yards. The current eruption has thus far caused a total topographic change in the crater that is equivalent to about two-thirds the volume of the old lava dome.

Posted by Raoul Ortega at 10:17 | Permalink

Views taken on 2005-Apr-19—21

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift westward early and north to north-northwestward later.

Recent observations: Overall the volcano is relatively quiet. Seismicity remains in the pattern of the past week, with small (~M1) earthquakes occurring about every three minutes or so. GPS receivers in the crater continue their slow rates of displacement, which suggests that the dome continues to extrude, albeit slowly. Rockfalls from the dome continue, and extrusion of lava on its north end is readily apparent. Crews yesterday deployed and surveyed several targets on dome, temporarily removed the GPS station on the dome, and collected ash and water samples. A new fact sheet summarizing highlights of activity from September 2004 through March 2005 is now available online at the USGS website.

Posted by Raoul Ortega at 10:02 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift southwestward.

Recent observations: Weather at the volcano is clear this morning as a nearly full moon brushes the western horizon. Seismicity remains in the pattern of the past week, with a ~M-1 earthquake occurring every other minute or so. The three GPS receivers in the crater continue their slow rates of displacement, which suggests that the dome continues to be extruded, albeit slowly. Crews yesterday repaired the voice-communication system that enables our radios when working around the volcano.

Posted by Raoul Ortega at 09:18 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift southwestward.

Recent observations: Crews had a very successful day yesterday. They collected samples of rocks and ash from the lava dome—some from very near the point where the whaleback emerges from the ground, deployed a new GPS unit on the dome, obtained aerial photographs for construction of a new digital elevation model to document topographic changes to the dome, and brought a seismic station on the old dome back online. If conditions are favorable tomorrow, crews plan to conduct gas measurements, conduct maintenance on a debris-flow warning station, and deploy survey targets on the new dome to obtain motion data that will complement that from the GPS unit. Seismicity remains in a relatively low state, with small quakes (M1-1.5) occurring about every 3 minutes.

Posted by Raoul Ortega at 10:41 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift south-southwestward.

Recent observations: The volcano is clear this morning. Overnight, a pair of rockfalls from the northeast side of the dome (at about 12:04 and 2:08 am) produced bright flashes visible on the JRO VolcanoCam, and this morning deposits from those events are plainly visible. Today, field crews plan to collect rock samples, gather new aerial photographs, and deploy GPS units on the new dome.

Posted by Raoul Ortega at 09:14 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift east-southeastward early in the day and southward later.

Recent observations: The volcano is obscured by clouds this morning, but weather forecasts suggest that clear, dry weather should return soon. If so, we plan to install GPS instruments on the new lava dome, conduct gas measurements, collect rock samples, gather new aerial photographs, and repair radio systems. At present, seismicity at the volcano is relatively quiet, with repetitive quakes occurring about once every few minutes. In conjunction with the relatively quiet seismicity, GPS instruments show that displacement of the old lava dome has slowed over the past several days. Such relative quiescence has been observed before in this eruption and does not mean that it is ending.

Posted by Raoul Ortega at 10:51 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift northeastward early in the day and eastward later.

Recent observations: The volcano is obscured by clouds this morning, but weather forecasts suggest that the coming week should be dry. If so, we plan to install seismic and GPS instruments on the new lava dome provided that good sites can be found. The disintegration of large parts of the dome during the past few weeks will make the search for sites challenging. Seismic and GPS instruments show no significant changes overnight.

Posted by Raoul Ortega at 10:58 | Permalink

Images taken on 2005-Apr-14

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift northeastward.

Recent observations: Almost 5 inches of rain have fallen in the crater during the past 24 hours. Streamflows have increased, but the intense rainfall has not triggered any lahars. Seismic and GPS instruments show no significant changes overnight.

Posted by Raoul Ortega at 11:01 | Permalink

Fieldwork photos taken on 2005-Apr-10

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift north-northeastward to eastward.

Recent observations: Seismicity has been relatively low the past several days, but imagery indicates that the dome is still extruding at a substantial rate and continuing to fracture. Yesterday, crews replaced a defective seismometer station in the crater and repaired radio communication systems. When weather permits, crews will conduct a gas-sensing flight, dredge rock samples from the dome, and take aerial photographs.

Also new:

Graph showing relationship between time and depth of earthquakes beneath Mount St. Helens from March 2004 through March 2005.

Posted by Raoul Ortega at 10:02 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift eastward to southeastward.

Recent observations: Weather permitting today several crews will head to the field to deploy GPS spiders on and near the new lava dome, repair a seismic station, conduct a gas-sensing flight, dredge rock samples from the dome, and take aerial photographs. Seismic and GPS data show no significant changes.

Posted by Raoul Ortega at 09:48 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift north-northeastward.

Recent observations: Data from field instruments indicates that seismicity remains unchanged and that points on the 1980-1986 lava dome are moving northward slowly as extrusion of the new lava dome continues. Laboratory analyses of ash from the 8 March explosion show that much of it consists of the finely pulverized material that forms on the outside of the nearly solid extrusion as it moves up from depth and grinds against the walls of its conduit. Presumably the explosion originated near the margin of the extrusion and blew out mostly this pulverized outer material.

Posted by Raoul Ortega at 10:33 | Permalink

Aerial views taken on 2005-Apr-10

New aerial photos of Mt.St.Helens available.

Posted by Raoul Ortega at 15:21 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift north-northeastward early and northeastward later.

Recent observations: Following a brief respite, storms have moved back into the region and several inches of new snow are expected to accumulate at the mountain. Ash deposits from dust clouds associated with continued rockfalls from the new dome will probably intermingle with and discolor new snow within the crater. If ash clouds rise above the rim, discolored snow may also be visible on the flanks when the weather clears again. Seismicity remains unchanged over the past few days, and is characterized by ongoing small quakes occurring once or twice per minute punctuated a few times per day by larger quakes. When conditions permit, crews will replace equipment pulled from the crater on Sunday, and make gas measurements and further observations.

Posted by Raoul Ortega at 10:29 | Permalink

• Mount St. Helens' dome takes on jagged look 2005-Apr-12 00:00 from The Seattle Times

  MOUNT ST. HELENS — Surging seismic activity at Mount St. Helens has changed the whale-back shape of the volcano's emerging dome, leaving it more like the back of a stegosaurus — a dinosaur with bony plates of armor along its spine.

  The outer edge of the jagged, platelike protrusions matches the smooth old whale-back profile, so it appears the new look reflects a sinking away of some segments of the dome, said David Sherrod at the U.S. Geological Survey's (USGS) Cascades Volcano Observatory, 50 miles away in Vancouver, Wash.

  also in The Portland Oregonian 2005-Apr-11 18:27

Posted by Raoul Ortega at 00:50 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift northeastward.

Recent observations: The volcano is blanketed with new snow, which mantles the region to below the 3000-ft altitude, judging from the clear views in the US Forest Service Volcano Cam this morning. Seismicity has decreased steadily in the past week, both by reduced number of larger earthquakes (M2.5-3.0) and decreasing size of the mid-range earthquakes. A GPS receiver located 200 m north of the new dome creeps steadily north-northwest at about 10 cm per day. Observations yesterday by helicopter in the crater and from a fixed station on the crater's eastern rim suggest the new dome continues to fracture and spread laterally. The process has been likened to “pancaking,” as the molten core yields and its solid carapace shatters. As a consequence, the dome's summit has been lowered broadly by a few tens of meters in the past two to three weeks, except for isolated high-standing remnants. Rockfalls and their associated rising dust clouds accompany this process. Virtually all these effects are limited to the dome and adjacent areas within 600 m radius, well within the crater. The combination of the GPS measurements adjacent to the dome and the qualitative estimate of lateral spreading suggest that extrusion of new lava continues. We still lack, however, an instrument on the new dome itself that might specify the rate and direction of propagation.

Also yesterday, two nonoperating GPS and sesmic monitoring stations in the crater were grappled by a helicopter sling line and pulled from the crater—scientific housekeeping, so to speak. A cover glass on our Sugarbowl dome cam (2.3 km from vent) was again replaced, owing to sandblasting by windborne sand and silt.

Posted by Raoul Ortega at 10:51 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift east-southeastward early and northeastward later in the day.

Recent observations: The volcano is mostly clear this morning. Crews plan to take advantage of the weather window to collect samples and do maintenance on a remote camera system.

Posted by Raoul Ortega at 08:40 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift east-southeastward.

Recent observations: The volcano is shrouded in clouds this morning. With one exception, instruments deployed Wednesday are transmitting signals back to the observatory. When weather permits, crews plan to measure gases, collect rock samples, obtain new photographs, and do maintenance on a remote camera and data communication systems.

Posted by Raoul Ortega at 10:57 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift northeastward.

Potential ash hazards to aviation: Under current eruptive conditions, small, short-lived explosions may produce ash clouds that exceed 30,000 feet in altitude. Ash from such events can travel 100 miles or more downwind.

Recent observations: Clear view of the crater this morning shows the new dome emitting a strong steam plume. With the deployment of new instrument packages in the crater on Wednesday our seismic and GPS coverage are nearly back to what they were prior to the March 8 explosion. Observations on Wednesday confirm that the dome is highly broken up and greatly crumbled. Now that the dome has endured another phase of decomposition we may see a new round of regeneration of the whaleback. Weather permitting, crews may attempt more field observations today.

Posted by Raoul Ortega at 10:12 | Permalink

Aerial views taken on 20045-Apr-06

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift northward early in the day and northeastward later.

Potential ash hazards to aviation: Under current eruptive conditions, small, short-lived explosions may produce ash clouds that exceed 30,000 feet in altitude. Ash from such events can travel 100 miles or more downwind.

Recent observations: Field crews took advantage of yesterday afternoon's clear conditions to make visual and thermal-sensing observations and to sling several new instruments into the crater by helicopter. As suspected from the pattern of seismicity and brief observations during the past couple of weeks, the smooth whaleback portion of the growing lava dome is now broken by numerous fractures and the edges have crumbled greatly. Several deep gashes on the east, north, and west sides frequently produce rockfalls and accompanying ash clouds. At least one ash cloud yesterday rose above the crater rim and drifted downwind dusting the new snow. Two of the instrument sites destroyed in the 8 March explosion were replaced. Sites on the northeast and south flanks of the old lava dome now each have two new spiders, one seismic and one GPS.

Update: 10:48 — Added link to photos

Posted by Raoul Ortega at 09:51 | Permalink

Aerial views taken on 2005-Apr-06

New aerial photos of Mt.St.Helens available.

Posted by Raoul Ortega at 18:20 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift north-northeastward.

Potential ash hazards to aviation: Under current eruptive conditions, small, short-lived explosions may produce ash clouds that exceed 30,000 feet in altitude. Ash from such events can travel 100 miles or more downwind.

Recent observations: The crater and growing lava dome are visible on the Forest Service's VolcanoCam this morning, although there is a moderate vapor plume obscuring some areas. Our DomeCam is still iced-up and isn't sending back any usable images. We hope to at least get some aerial views today. Wind and vapor conditions make helicopter slinging of instruments unlikely.

Posted by Raoul Ortega at 09:58 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift northward to northeastward.

Potential ash hazards to aviation: Under current eruptive conditions, small, short-lived explosions may produce ash clouds that exceed 30,000 feet in altitude. Ash from such events can travel 100 miles or more downwind.

Recent observations: Yesterday a field crew repaired the satellite telemetry system near Coldwater Visitors Center that sends data from several instruments and a camera back to CVO. Another of the larger (greater than magnitude 3) earthquakes that occur intermittently was recorded at about 9:15 p.m. last night (M=3.3). No significant changes in activity have been detected during the past day.

Posted by Raoul Ortega at 09:30 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift eastward at lower altitude and southeastward at higher altitude.

Potential ash hazards to aviation: Under current eruptive conditions, small, short-lived explosions may produce ash clouds that exceed 30,000 feet in altitude. Ash from such events can travel 100 miles or more downwind.

Recent observations: As has happened on several occasions during the lava-dome-building phase of the eruption, a series of large (equal to or greater than magnitude 3) earthquakes are being produced, in addition to the typical array of smaller events. Three large earthquakes occurred during the past 24 hours. The largest, magnitude 3.4, at 10:45 p.m. (PDT) last night is the largest recorded at St. Helens since early October. The exact cause of these larger events is unknown, but they are usually associated with time periods during which the whaleback portion of the lava dome is breaking up. The earthquakes don't represent the surficial disintegration or sliding of rock slabs off the dome, but rather slip on fractures deeper in the dome or conduit. Such behavior may be the result of increased resistance to extrusion as the whaleback gets longer, steeper, or pushes against the crater wall.

Posted by Raoul Ortega at 10:56 | Permalink

Potential ash hazards: The usual wind forecasts from the National Oceanic and Atmospheric Administration (NOAA) are not available today, but recent observations and other forecasts from NOAA show that any ash clouds that rise above the crater rim today would drift north-northeastward to northeastward.

Potential ash hazards to aviation: Under current eruptive conditions, small, short-lived explosions may produce ash clouds that exceed 30,000 feet in altitude. Ash from such events can travel 100 miles or more downwind.

Recent observations: Seismic activity remains unchanged from recent days and the volcano remains obscured by storm clouds.

Posted by Raoul Ortega at 10:54 | Permalink

Potential ash hazards: The usual wind forecasts from the National Oceanic and Atmospheric Administration (NOAA) are not available today, but recent observations and other forecasts from NOAA, coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift northeastward to eastward.

Potential ash hazards to aviation: Under current eruptive conditions, small, short-lived explosions may produce ash clouds that exceed 30,000 feet in altitude. Ash from such events can travel 100 miles or more downwind.

Recent observations: Seismic activity remains unchanged from recent days. Views of the volcano on Thursday showed that the south end of the growing lava dome was much more broken up than when last seen about two weeks ago. Such a condition is consistent with the spate of larger earthquakes that has occurred during this same time period, and is reminiscent of activity during mid-December. A field crew will perform repairs on our satellite telemetry station near Coldwater Visitors Center today.

Posted by Raoul Ortega at 11:28 | Permalink

Potential ash hazards: Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that any ash clouds that rise above the crater rim today would drift northeastward early and east-northeastward as the day progresses.

Potential ash hazards to aviation: Under current eruptive conditions, small, short-lived explosions may produce ash clouds that exceed 30,000 feet in altitude. Ash from such events can travel 100 miles or more downwind.

Recent observations: After a one-day respite Cascades winter weather has returned, cloaking the mountain in clouds, rain, and snow. Overnight images from the VolcanoCam show a few bright flashes, which likely represent rockfall from the dome. Ongoing crumbling of the dome is to be expected from the style of sustained dome emplacement the volcano is experiencing. The National Weather Service's forecast indicates we can expect little relief from storms over the next several days. Data from seismic and GPS stations show no significant changes in the level of activity over the past day.

Posted by Raoul Ortega at 10:41 | Permalink