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2004 October 31

USGS Update 2004-0ct-31 10:00

Current Update

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky.

Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

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

Seismicity remains at a low level compared to that observed early in this unrest. The current seismicity is consistent with a continuing, slow rise of magma driving uplift of the crater floor and feeding a surface extrusion of lava. The overall low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor, thereby reducing the probability of highly explosive eruptions in the near term.

Crews did not go the field yesterday because of inclement weather. No field work is planned for today.

2004 October 30

USGS Update 2004-0ct-30 10:00

Current Update

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky.

Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

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

Seismicity remains at a low level compared to that observed early in this unrest. The current seismicity is consistent with a continuing, slow rise of magma driving uplift of the crater floor and feeding a surface extrusion of lava. The overall low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor, thereby reducing the probability of highly explosive eruptions in the near term.

The new GPS station on the southern part of the new dome (uplifted glacial ice, rock debris, and new lava) shows continued southward motion—about 10 m since October 28; a station near the summit of the old dome shows continued slow northward motion.

Crews did not go the field yesterday because of inclement weather. No field work is planned for today for the same reason.

2004 October 29

USGS Update 2004-0ct-29 10:00

Current Update

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky.

Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

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

Seismicity remains at a low level compared to that observed early in this unrest. The current seismicity is consistent with a continuing, slow rise of magma driving uplift of the crater floor and feeding a surface extrusion of lava. The overall low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor, thereby reducing the probability of highly explosive eruptions in the near term.

The new GPS station on the southern part of the new dome (uplifted glacial ice, rock debris, and new lava) shows continued southward motion—about 6 m in the past 36 hours; a station near the summit of the old dome shows continued slow northward motion. GPS, LIDAR, and photogrammetric measurements, in combination with visual observations over recent days suggest that the dome complex is spreading outward at its margins similarly to the expected behavior of a viscous lava flow.

Crews did not go the field yesterday because of inclement weather. No field work is planned for today for the same reason.

Latest Updates

  • Scientists edge closer to predicting volcanic eruptions 2004-Oct-29 00:47 from The Seattle Times

    Scientists monitoring Mount St. Helens got a lot of things right over the past month, as they scrambled to figure out what the restless volcano would do.

    They said lava would probably reach the surface, and it did. They said not to expect anything like the catastrophic eruption of May 18, 1980, and so far, all of the outbursts have been modest.

2004 October 28

USGS Update 2004-0ct-28 10:00

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky.

Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

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

Seismicity remains at a low level compared to that observed early in this unrest. The current seismicity is consistent with a continuing, slow rise of magma driving uplift of the crater floor and feeding a surface extrusion of lava. The overall low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor, thereby reducing the probability of highly explosive eruptions in the near term.

Preliminary reduction of LIDAR data from October 14 indicates that the volume increase of the new dome (uplifted glacial ice, rock debris, and new lava) was approximately 11 million cubic meters at that time, giving a growth rate of about 7 cubic meters per second.

Crews had a productive day in the field yesterday. Work included installation of two new GPS stations to measure ground deformation on the surface of the growing dome, geologic observations and sampling, collection of oblique stereophotos for tracking growth of the new dome, thermal-infrared mapping to determine temperature distribution in the new and old (1980-86) domes, a gas-measurement flight, and telemetry maintenance. Results include the following: the new GPS station on the southern part of the new dome shows motion downward and to the southeast; a station near the summit of the old dome has moved northward about 7 cm since October 20; thermal imaging showed an elongate band of elevated surface temperature, locally as great as 775º C along the west face of the new dome coincident with the area of exposed newly extruded lava; gas-emission rates measured yesterday are similar to recent previous measurements (SO2 about 250 tons per day, CO2 about 300 tons per day, H2S about 2 tons per day); samples of dome rock similar in appearance to the rock of the older dome were collected from two localities in the vicinity of the exposed new lava. In the aggregate, the above results indicate that the character and rise of magma is continuing as it has over tha past few weeks. The visible steam plume is caused by condensation of moisture in the cold air above the hot dome.

No field work is planned for today.

Latest Updates

  • Does river foretell eruptions of Mount St. Helens? After the Kalama turns white, residents say, volcano acts up 2004-Oct-25 from The Seattle Post-Intellegencer

    KALAMA RIVER -- Forget the seismometers.

    The global positioning systems, infrared cameras -- chuck all that new-fangled gadgetry, too.

    For out here, along this wild, winding stream, the locals know something the scientists don't: Sometimes, this river speaks. And when it comes to Mount St. Helens, its waters tell the future.

  • Experts Discuss Health Impacts Of Volcanic Fallout 2004-Oct-28 05:59 from KING (ch.5) Seattle

    SEATTLE -- When Mount St. Helen [sic] erupted in 1980, it created a living laboratory for scientists -- notably specialists in volcanoes, affected forests, river systems, wildlife -- and human health

    But health experts "looked in the wrong place. We basically missed the boat," Dr. Dorsett D. Smith said Wednesday during a discussion of volcano health effects at the 70th annual international scientific assembly of the American College of Chest Physicians.

2004 October 27

USGS Update 2004-0ct-27 10:00

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky.

Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

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

Seismicity remains at a low level compared to that observed early in this unrest. The current seismicity is consistent with a continuing, slow rise of magma driving uplift of the crater floor and feeding a surface extrusion of lava. The overall low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor, thereby reducing the probability of highly explosive eruptions in the near term.

Samples of the new dacite lava collected on 20 October are mostly similar chemically and texturally to lava erupted during the late period of dome growth in the 1980's (1984-1986). This is consistent with slow rise, degassing, and cooling of magma within the volcano's conduit. However, a minor component of the 10/20/04 sample has textures and mineral compositions indicative of rapid ascent of magma from a region at greater depth and greater temperature (900º C).

Crews did not go to the field yesterday, but field work including geologic and thermal-imaging observations, a gas-measurement flight, and telemetry maintenance is under way.

2004 October 26

USGS Update 2004-0ct-26 10:00

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky.

Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

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

Seismicity remains at a low level compared to that observed early in this unrest. The current seismicity is consistent with a continuing, slow rise of magma driving uplift of the crater floor and feeding a surface extrusion of lava. The overall low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor, thereby reducing the probability of highly explosive eruptions in the near term.

Crews did not go to the field yesterday, but field work is planned for tomorrow and Thursday if the weather improves.

2004 October 25

USGS Update 2004-0ct-25 10:00

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky.

Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

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

Seismicity remains at a low level compared to that observed early in this unrest. The current seismicity is consistent with a continuing, slow rise of magma driving uplift of the crater floor and feeding a surface extrusion of lava. The overall low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor, thereby reducing the probability of highly explosive eruptions in the near term.

Yesterday field crews were able to make brief geological and thermal-imaging observations and to install an additional GPS receiver. Thick steam clouds obscured much of the new lava dome, but some changes were apparent since the last observations on 21 October. A small apron of warm ash and blocks that fell from the dome lies on newly fallen snow on its west side and a small stream of melt water flows from a nearby area of intensely deformed glacier ice. A new GPS instrument was slung by helicopter and placed on a large boulder just north of the 1980-86 lava dome. It will aid in detecting any crater-wide deformation. Initial analyses were made over the weekend of samples of the new lava dome that were collected on 20 October. They show that, since lava first appeared on 11 October, it has been rising more easily from depth and not spending much more than a few days at shallow levels before being extruded onto the surface. Reviews of several lines of evidence confirm that the average rate of volume change between late September and mid-October of the deformed area and new lava dome was about 8 cubic meters (10 cubic yards, or a typical dump truck full) per second. A substantial part of that change must be magma, which suggests a rate similar to that of many other lava-dome-building eruptions.

2004 October 24

Latest Updates

  • New Lava Lobe On Mount St. Helens Is 'Huge' 2004-Oct-22 06:06 from KIRO (ch.7) Seattle/Associated Press

    SEATTLE -- The new lobe on the lava dome in Mount St. Helens' crater has grown to roughly the size of an aircraft carrier.

    After getting a good look into the crater, U.S. Geological Survey scientists said the new feature is about 900 feet long, 250 feet wide and 230 feet high.

  • Weather hampers Mount St. Helens monitoring 2004-Oct-24 10:07 from KING (ch.5) Seattle/NW Cable News

    MOUNT ST. HELENS, Wash. -- Rain and clouds Saturday again hampered efforts by the U.S. Geological Survey to monitor the restless Mount St. Helens volcano.

    Due largely to low clouds, a remote-control monitoring plane has not been an immediate help to scientists, but it shows promise. Poor viewing conditions with rain were forecast throughout the weekend.

USGS Update 2004-0ct-24 11:00

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky.

Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

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

Seismicity remains at a low level compared to that observed early in this unrest. The current seismicity is consistent with a continuing, slow rise of magma driving uplift of the crater floor and feeding a surface extrusion of lava. The overall low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor, thereby reducing the probability of highly explosive eruptions in the near term.

No field work was possible yesterday owing to poor weather. Today field crews will attempt to make geological and thermal-imaging observations and to take aerial photographs for use in estimating the rate of growth of the new lava dome and the deforming area.

2004 October 23

USGS Update 2004-0ct-23 11:00

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky.

Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that ash clouds that rise above the crater rim today would drift eastward from the volcano. Seismicity remains at a low level compared to that observed early in this unrest. The current seismicity is consistent with a continuing, slow rise of magma driving uplift of the crater floor and feeding a surface extrusion of lava. The overall low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor, thereby reducing the probability of highly explosive eruptions in the near term.

No geological or thermal-imaging observations were possible yesterday owing to poor weather. No field work is planned for today, but missions are being planned for Sunday.

2004 October 22

USGS Update 2004-0ct-22 10:10

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky.

Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

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

Seismicity remains at a low level compared to that observed early in this unrest. The current seismicity is consistent with a continuing, slow rise of magma driving uplift of the crater floor and feeding a surface extrusion of lava. The overall low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor, thereby reducing the probability of highly explosive eruptions in the near term.

In spite of deteriorating weather conditions yesterday, geological and thermal-imaging observations were possible and indicated that both the area of uplift and the new lava extrusion have grown noticeably since viewed on the previous day. The area of uplift and intense deformation continues to move southward and is nearing the crater wall. Intense steaming prohibited detailed estimates of dimensions, but the new lava extrusion, which has a volume of about 2 million cubic yards, displayed a new protrusion that had a maximum temperature of about 650 degrees C (1200 degrees F).

Any field work today will be limited to maintenance of telemetry systems.

2004 October 21

USGS Update 2004-0ct-21 10:45

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky.

Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

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

In the past 24 hours, seismicity has decreased somewhat and remains at a low level compared to that observed early in this unrest. The current seismicity is consistent with a continuing, slow rise of magma driving uplift of the crater floor and feeding a surface extrusion of lava. Last night, glow from this new lava was intermittently visible on the U.S. Forest Service web camera. The overall low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor.

Yesterday was a busy day in the field. Geological and thermal-imaging observations confirmed that both the area of uplift and the new lava extrusion have increased in size noticeably since last seen on October 14. The area of uplift and intense deformation continues to move southward and is nearing the crater wall. About 1 foot of new snow with a light dusting of ash covers much of the uplift, except for the new lava extrusion, which is steaming heavily. The new lava extrusion, which occupies the western part of the uplift, is now about 900 ft long by 250 ft wide and 230 ft high and has a volume of almost 2 million cubic yards. Its maximum temperature is about 600 degrees C (1100 degrees F). Rock samples from the new lava extrusion were collected from a helicopter by using a bucket slung on a 100-ft line. The samples look like typical Mount St. Helens lava, called dacite. Further detailed analyses of the samples will help to answer questions about the character of the magma driving the eruption and how it relates to lava erupted in the 1980s.

A gas-sensing flight detected low levels of the volcanic gases carbon dioxide, sulfur dioxide, and hydrogen sulfide, which is consistent magma continuing to rise from depth.

Test flights of the Unmanned Aerial Vehicles (UAVs), which will hopefully be used for monitoring the crater area in the future, were conducted yesterday close to the Johnston Ridge Observatory. More tests are scheduled for today if weather conditions permit.

Field crews will attempt to obtain additional geological and thermal-imaging observations today. Other work will continue on maintenance of instrumentation and improving our telemetry systems.

2004 October 20

Latest Updates

  • Dome continues to grow at Mount St. Helens 2004-Oct-20 18:45 from KING (ch.5) Seattle

    SEATTLE — Scientists got their first good look at Mount St. Helens Wednesday after the clouds cleared up, revealing a snow covered volcano still steaming and the new dome growing slowly but steadily.

    Clouds and fog had obscured the crater since before last weekend, but the clearing allowed scientists to calculate and confirm the new dome was growing in size and that new lava was still pushing up to the surface.

USGS Update 2004-0ct-20 11:00

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky.

Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that ash clouds that rise above the crater rim today would drift to the west and southwest from the volcano.

In the past 24 hours, seismicity has decreased somewhat and remains at a low level compared to that observed early in this unrest. The current seismicity is consistent with a continuing, slow rise of magma driving uplift of the crater floor and feeding a surface extrusion of lava. Last night, glow from this new lava was intermittently visible on the U.S. Forest Service web camera. The overall low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor.

Poor weather yesterday again prevented geological observations. When last seen during an overflight on October 14, estimated dimensions of the new lava extrusion were approximately 110 x 70 meters (360 x 230 ft) in length and height and about 18 m (58 ft) in width. The maximum temperature recorded on October 14 during the last successful overflight of the crater area, was 761 degrees C (1400 degrees F).

Today, weather conditions have improved considerably and field crews are flying this morning to obtain new photographs, video, thermal images, and other data. Preliminary reports from the field indicate that the new lava dome has increased in width since October 14 and much of the fin-shaped lava spine described earlier has collapsed. Some ash likely related to small avalanches from the spine and possibly small ash emissions is visible on snow inside the crater. A vigorous steam plume is rising to approximately 10,000 feet above sea level.

A gas measurement flight is planned for later in the day. Other field crews are conducting maintenance on instrumentation and improving our telemetry systems.

2004 October 19

USGS Update 2004-0ct-19 10:00

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky. Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that ash clouds that rise above the crater rim today would drift to the northwest, north, and northeast from the volcano.

In the past 24 hours, seismicity has not changed significantly and remains at a low level overall. Continuing storm noise explains some of the higher background signal observed. We have no new Global Positioning System (GPS) measurements to report. Poor weather yesterday again prevented geological observations.

The current level and character of seismicity are consistent with a continuing rise of magma driving uplift of the crater floor and feeding the surface extrusion of lava. Low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor.

When weather conditions improve, we will continue geologic observations, thermal imaging, and making improvements in telemetry systems.

2004 October 18

Latest Updates

  • St. Helens continues to build lava dome 2004-Oct-18 from The Seattle Post-Intellegencer

    Mount St. Helens continued the slow process of building a new lava dome in its crater yesterday with still more lava pushing to the surface, geologists reported.

  • Lava dome continues building on Mount St. Helens 2004-Oct-17 16:53 from KGW (ch.8) Portland/NW Cable News

    MOUNT ST. HELENS, Wash. -- Growth of the new lava dome inside the crater of Mount St. Helens continued over the weekend, scientists said, indicating that lava remains quietly pushing into the crater.

USGS Update 2004-0ct-18 11:00

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. At this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky. Although considered less likely at this time, the current eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that ash clouds that rise above the crater rim today would drift to the east and then to the north and northeast later this afternoon.

Seismicity has not changed significantly and remains at a low level overall. Continuing storm noise explains some of the higher background signal observed. We have no new Global Positioning System (GPS) measurements to report. Poor weather yesterday prevented geological observations.

The current level and character of seismicity are consistent with a continuing rise of magma driving uplift of the crater floor and feeding the surface extrusion of lava. Low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor. When weather conditions improve, we will continue geologic observations, thermal imaging, and making improvements in telemetry systems.

2004 October 17

USGS Update 2004-0ct-17 10:45

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Under current conditions, small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if they are triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. Such lahars pose negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people along the river channel upstream of the SRS. Owing to weather and stream-flow conditions at this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky. Although considered less likely at this time, eruptive activity could evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

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 will drift northeastward to eastward later in the day.

Seismicity has increased slightly in the past 24 hours, but remains at a low level overall. Some of the higher seismicity is due to storm noise. Overnight, rainfall triggered a small debris flow that flowed north from the crater and changed rapidly to muddy streamflow within 5 km of the volcano. Global Positioning System (GPS) measurements continue to indicate only minor deformation of the northern part of the 1980-86 lava dome and no deformation of the outer flanks of the volcano. Poor weather yesterday prevented geological observations.

The current level and character of seismicity are consistent with a continuing rise of magma driving uplift of the crater floor and feeding the surface extrusion of lava. Low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor.

Field crews will not be out in today's poor weather. When weather conditions improve, we will continue geologic observations, thermal imaging, and making improvements in telemetry systems.

2004 October 16

Latest Updates

  • Mount St. Helens' Fin May Be Splitting 2004-Oct-16 from KOMO (ch.4) Seattle

    SEATTLE - The stone "fin" on the new lava lobe inside the crater at Mount St. Helens seems to be starting to split.

    The fin, which is about 200 feet tall and 300 feet wide, is building on the new lava dome, which is about 1,600 feet in diameter and 400 feet high, U.S. Geological Survey geologist Tina Neal said Friday.

  • Mount St. Helens fin may be splitting 2004-Oct-16 12:42 from NW Cable News/Associated Press

    SEATTLE — The stone "fin" on the new lava lobe inside the crater at Mount St. Helens seems to be starting to split.

    The fin, which is about 200 feet tall and 300 feet wide, is building on the new lava dome, which is about 1,600 feet in diameter and 400 feet high, U.S. Geological Survey geologist Tina Neal said Friday.

USGS Update 2004-0ct-16 11:00

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Under current conditions, small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if they are triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. Such lahars pose negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people working or recreating along the river channel upstream of the SRS. Furthermore, due to weather and stream-flow conditions at this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky. Although considered less likely at this time, eruptive activity could also evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

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 will drift east-southeastward to eastward later in the day.

During the past 24 hours, seismicity has remained at a low level. Global Positioning System (GPS) measurements continue to indicate only minor deformation of the northern part of the 1980-86 lava dome and no deformation of the outer flanks of the volcano. Poor weather yesterday limited geological observations to a few time-lapse pictures from the video camera at Sugar Bowl and brief views from Johnston Ridge Observatory. Parts of the area of uplift and new lava dome visible from those points were higher than when last seen on 14 October.

Our recent observations are consistent with ongoing rise of magma driving the uplift and feeding the surface extrusion of lava. Low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor.

Today, field crews will continue geologic observations, thermal imaging, and improvements in telemetry systems if weather conditions permit.

2004 October 15

USGS Update 2004-0ct-15 11:00

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Growth of the new lava dome inside the crater of Mount St. Helens continues. As long as this eruption is in progress, episodic changes in the level of activity can occur over days, weeks, or even months. Increase in the intensity of eruption could occur suddenly or with very little warning and may include explosive events that produce hazardous conditions within several miles of the volcano. Under current conditions, small lahars (volcanic debris flows) could suddenly descend the Toutle River valley if they are triggered by heavy rain or by interaction of hot rocks with snow or glacier ice. Such lahars pose negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people working or recreating along the river channel upstream of the SRS. Furthermore, due to weather and stream-flow conditions at this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky. Although considered less likely at this time, eruptive activity could also evolve into a more explosive phase that affects areas farther from the volcano and sends significant ash thousands of feet above the crater where it could be a hazard to aircraft and to downwind communities.

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 will drift southeastward.

During the past 24 hours, seismicity has remained at a low level. Global Positioning System (GPS) measurements continue to indicate only minor deformation of the northern part of the 1980-86 lava dome and no deformation of the outer flanks of the volcano. A gas-sensing flight yesterday found conditions unchanged from Wednesday with a low flux of sulfur dioxide and no detectable carbon dioxide or hydrogen sulfide. Yesterday's geological observations and thermal imaging of the new lava dome indicate continued slow extrusion of lava. In addition, the surrounding uplifting and intensely deforming area on the south side of the 1980-86 lava dome and adjoining glacier continues to broaden.

Our recent observations are consistent with ongoing rise of magma driving the uplift and feeding the surface extrusion of lava. Low rates of seismicity and gas emission suggest that the lava reaching the surface is gas poor.

Today, field crews will continue geologic observations, thermal imaging, and improvements in telemetry systems.

We continue to monitor the situation closely and will issue additional updates and changes in alert level as warranted.

Latest Updates

  • Mount St. Helens' other big news -- a growing glacier 2004-Oct-15 from The Seattle Post-Intellegencer/Associated Press

    MOUNT ST. HELENS -- While earthquakes, steam and lava are getting all the attention on Mount St. Helens these days, the volcano's most unusual feature could be the icy epitome of slow motion that has sprouted on its flanks in the last two decades: its glacier.

  • Mount St. Helens oozing new lava 2004-Oct-15 08:37 from KING (ch.5) Seattle/Associated Press

    SEATTLE — Scientists were gearing up Friday to see what's inside Moun St. Helens' crater where new lava continues to ooze, expanding the growing rock formation behind the volcano's old lava dome

  • More Lava Emerges On Crater Floor 2004-Oct-14 05:55 (Update: 2004-Oct-15 06:09) from KIRO (ch.7) Seattle

    MOUNT ST. HELENS, Wash. -- More new lava emerged on the crater floor of Mount Saint Helens Thursday, expanding the growing rock formation behind the volcano's old lava dome and emitting a red glow at night.

2004 October 14

USGS Update 2004-0ct-14 18:15

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Seismic activity remained at a low level today. Today'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. Yesterday's gas-sensing flight detected low levels of sulfur dioxide and hydrogen sulfide, but no carbon dioxide. Abundant steam continues to rise from the area of lava extrusion to the crater rim, from which it is being dispersed downwind. Measurements taken yesterday of flow-rate and temperature in streams draining the crater showed no significant change from late September values.

Other field work today included a gas-sensing flight (data not yet reduced), downloading GPS data, and servicing GPS stations.

Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), combined with eruption models, show that any ash clouds will drift south-southeastward 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. Small emissions of steam and ash are possible. Reflection onto steam clouds of incandescence or glow from the hot rock and gases will be visible at night from some locations.

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. We expect fluctuations in the level of eruptive activity to continue. Escalation could occur suddenly. Therefore, we continue to monitor the situation closely and will issue additional updates and changes in alert level as warranted.

Under current conditions, small lahars (volcanic debris flows) could be triggered if hot material from the new lava extrusion swiftly melts glacier ice. Such lahars pose negligible hazard below the Sediment Retention Structure (SRS), but could pose a hazard to people working or recreating along the river channel upstream of the SRS. Furthermore, due to weather and stream-flow conditions at this time of year, it is not unusual for rivers draining the volcano to contain high concentrations of sediment that turn the water murky.

There will no longer be daily media briefings at the Headquarters of the Gifford Pinchot National Forest. A media briefing will be held tomorrow at 1 p.m. at Castle Lake Viewpoint in the Mount St. Helens National Volcanic Monument. However no additional such briefing are planned until conditions warrant them. Beginning tomorrow, we will release only one daily update, at approximately 11 a.m. Tomorrow's update will contain information regarding media contacts with the Joint Information Center.

Latest Updates

  • Mount St. Helens adds to new dome 2004-Oct-14 from The Seattle Post-Intellegencer

    Mount St. Helens continued to reveal its inner self yesterday as additional glowing lava pushed to the surface in the volcano's crater.

  • Slow Eruption Makes Mount St. Helens Glow At Night 2004-Oct-14 05:55 from KIRO (ch.7) Seattle

    MOUNT ST. HELENS, Wash. -- Molten rock rising inside Mount St. Helens is giving the volcano an eerie red glow at night.

  • New St. Helens dome producing eerie glow 2004-Oct-14 08:23 from KING (ch.5) Seattle

    MOUNT ST. HELENS, Wash. — The ongoing dome-building eruption at Mount St. Helens has produced glowing red lava that can be seen in nighttime aerial views of the peak, scientists say.

  • Mount St. Helens' lava dome grows steadily 2004-Oct-14 08:01 from The Seattle Times

    Molten rock continued to punch through the crater of Mount St. Helens yesterday, adding to a new lava dome and holding out the prospect of prime sightseeing, as long as the weather remains clear.

USGS Update 2004-0ct-14 07:00

Current Update

Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE

Seismic activity remained at a low level overnight, little changed from yesterday. Wednesday's visual observations and thermal imaging of the crater focused on the intensely deforming and uplifting area on the south side of the 1980-86 lava dome and on the new lobe of lava in the western part of that area. The areas of both the uplift and the new lobe of lava are still increasing. 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, where it dispersed southwestward in strong winds.

Other field work on Wednesday included a gas-sensing flight (data not yet reduced), downloading GPS data, and observations of water flows and temperatures in streams draining the crater. Today's fieldwork will include a thermal imaging flight, geologic observations, and instrument maintenance.

Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), combined with eruption models, show light north to northwesterly winds this morning. Any ash clouds will drift generally south to southeastward.

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 and may include explosive events. We continue therefore to monitor the situation closely and will issue additional updates and changes in alert level as warranted.

2004 October 13

USGS Update 2004-0ct-13 18:00

Current Update

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.

Latest Updates

  • Dome-building eruption creates eerie red glow at St. Helens Update: 2004-Oct-13 12:50 from The Seattle Times

    SEATTLE — The ongoing dome-building eruption at Mount St. Helens could last for days, weeks or months, and nighttime views of the peak now include a red glow from lava surfacing at nearly 1,300 degree Fahrenheit, scientists said today.

    Clouds also can reflect the glow of red-hot stone, geologist Tina Neal of the U.S. Geological Survey told a news conference.