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2005 July 31

News Report Update

  • 3.3 earthquake rumbles under Mount St. Helens 2005-Jul-31 14:31 from The Seattle Times

    VANCOUVER, Wash. — A 3.3-magnitude earthquake trembled beneath Mount St. Helens early this morning, the latest in a series of stronger than usual quakes at the volcano.

    The quake at 2:34 a.m. likely triggered the overnight collapse of large section of rock at the north end of the growing lava dome, U.S. Geological Survey scientists reported Sunday from the Cascades Volcano Observatory.

USGS Update 2005-Jul-31 10:00

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: Another large section of the spine at the north end of the growing lava dome collapsed overnight in a rockfall. An M=3.3 earthquake at about 2:34 a.m. this morning was the likely trigger. Much of the smooth surface of the spine, which is created as it extrudes from the vent, has now been removed by rockfalls over the past few weeks. A minor mistake was made in the gas measurements reported in Friday's (July 29) update. The correct sulfur dioxide value is 60 tonnes per day, not 80 as reported.

2005 July 30

USGS Update 2005-Jul-30 10:00

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: Rockfalls continue to topple the growing lava dome and produce minor ash plumes. A rockfall yesterday morning removed a large piece of the northeast part of the active lava spine and wafted an ash plume above the crater rim. Images from the camera on the SugarBowl dome near the crater mouth show that the lave spine continues to emerge.

2005 July 29

USGS Update 2005-Jul-29 10:00

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: Rockfalls and associated minor ash plumes continue to be generated from the growing lava dome. Yesterday crews were able to install a new seismic spider on the east side of the new lava dome. It replaces an important station that was destroyed recently by the advancing apron of rockfall debris. A couple of GPS spiders and one seismic spider on the glacier were moved slightly to avoid being swallowed in growing crevasses. Results of a flight on Wednesday show emission rates of volcanic gases remain little changed—about 80 tonnes per day of sulfur dioxide and 880 tonnes per day of carbon dioxide. Analysis of a rock sample collected from the dome on July 13 shows no change in the composition of lava being extruded.

2005 July 28

USGS Update 2005-Jul-28 08:05

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 east-northeastward, except at low altitudes later in the day when they could also drift southeastward.

Recent observations: Rockfalls continue to topple the growing lava dome. A rockfall associated with a minor steam and ash emission and M2.3 earthquake at 12:05pm yesterday lofted a photogenic ash plume above the rim. Crews are out again today continuing to make GPS measurements on the volcano's flanks, repairing communications systems, and retrieving and moving instrument packages in the crater.

2005 July 27

Views and panoramas

A few photos and some QuickTimeVR panoramas from a visit on 2005-Jul-27.

USGS Update 2005-Jul-27 08:15

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 generally southward to eastward, except at low altitudes where they could also drift westward.

Recent observations: Rockfalls continue to topple the steep spine on the growing lava dome, and its height has been now been greatly diminished. Crews had a busy and productive field day yesterday, and are out again today to make more GPS measurements on the volcano's flanks, to continue geologic mapping of the mountain, and to measure volcanic gases.

2005 July 26

USGS Update 2005-Jul-26 10:10

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 southeastward, except at low altitude this morning when they could also drift westward.

Recent observations: Rockfalls continue to occur from the steep spine on the growing lava dome. One happened a short time ago and produced a diffuse ash cloud visible from the metropolitan area that just cleared the crater rim. Last evening's (shortly after 9 p.m. PDT) M=5.6 earthquake in southwestern Montana was clearly recorded on the seismic stations around Mount St. Helens as a several-minutes-long signal. Several crews are at work in the field. A program starts today to systematically sample spring waters from the crater and flanks of the volcano. Volcanic gases can be dissolved in ground water and slightly increase levels of chloride, sulfate, and other chemicals. Heat can also raise the temperature of the water.

2005 July 25

USGS Update 2005-Jul-25 09:20

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 southeastward early in the day and southward to southwestward later.

Recent observations: Numerous rockfalls continue from the lava dome, but there have been none of the larger (magnitude about 3) earthquakes during the past 24 hours. Successive images from the Sugar Bowl DomeCam show that the lava spine at the north end of the dome continues to extrude at a rate similar to that of the past few weeks. But the rate of rockfall is greater and the altitude of the top of the spine is decreasing. Crews plan to work in the field on Tuesday and Wednesday of this week.

2005 July 24

USGS Update 2005-Jul-24 09:50

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 early in the day and southward to southeastward later.

Recent observations: A magnitude 3.3 earthquake at about 3:30 a.m. this morning triggered another large rockfall from the tip of the growing spine on the new lava dome. About 8:30 last evening a large rockfall without an apparent earthquake trigger generated an ash cloud that was observed drifting over the crater rim. Patterns of seismicity and ground deformation in the crater remain unchanged from those that have become well established during the past few weeks.

2005 July 23

USGS Update 2005-Jul-23 09:15

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 east-northeastward.

Recent observations: Two earthquakes a bit larger than magnitude 3 occurred during the past 24 hours, adding to the 5 similar such events of the past week. Clouds permitted only limited views of the new lava dome yesterday, but rockfalls removed noticeable portions of the steep spine between 4 and 5 p.m. yesterday afternoon and between 8 p.m. last night and 7 a.m. this morning, probably coincident with M=2.5 and M=3.2 earthquakes, respectively. The top and flanks of the steep spine are greatly fractured and additional rockfalls are expected, especially coincident with the larger earthquakes.

2005 July 22

USGS Update 2005-Jul-22 10:15

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 in the day and eastward to east-southeastward later.

Recent observations: Brief glimpses of the new lava dome from the Sugar Bowl DomeCam early this morning show a vapor plume rising above the growing lava dome. Overnight rain has settled the dust that was blowing around the crater yesterday and has created atmospheric conditions favorable for a visible vapor plume. Numerous rockfalls occurred overnight as revealed by flashes of light on the VolcanoCam. Analysis of a digital elevation model created from aerial photographs taken on June 15 shows that the volume of the new lava dome was about 54 million cubic meters (70 million cubic yards), or about 60% of the volume of the lava dome that grew in the crater from 1980 to 1986. The rate of addition of lava to the dome from mid-May to mid-June remained at about 1.5 cubic meters (2 cubic yards) per second. The high point of the lava dome (the actively growing spine) on June 15 was 2335 meters (7660 feet), but it is currently lower than that owing to the recent large rockfalls from the spine.

2005 July 21

USGS Photo Update

New views of the lava dome showing changes taking place due to (or causing) earthquake activity.

News Report Update

  • Chicken-egg question arises over quakes, rockfall from rising dome 2005-Jul-21 13:24 from The Portland Oregonian

    SEATTLE (AP) — There's a whole lotta shakin' going on at Mount St. Helens these days as the restless peak does what it has for thousands of years: build new lava domes for itself that totter and fall and then serve as the foundation for future domes.

    A series of stronger than usual earthquakes — exceeding magnitude 3 — has been reported in recent days by the Cascades Volcano Laboratory in Vancouver, Wash., about 50 miles south of the mountain. The latest was a magnitude 3.1 quake early Thursday that was accompanied by a rockfall.

USGS Update 2005-Jul-21 09:30

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 early in the day and northeastward later.

Recent observations: Several large rockfalls occurred overnight. The first was at about 9:30 p.m. and produced an ash cloud that drifted eastward over the crater rim. Another occurred about 3 a.m. and was accompanied by an M=3.1 earthquake. Views from the Sugar Bowl DomeCam this morning show that the top of the growing spine at the north end of the new lava dome collapsed and that a large crack is forming on the spine. Development of such cracks increases the probability of more rockfalls and accompanying ash clouds during the coming days.

2005 July 20

USGS Update 2005-Jul-20 08:30

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.

Recent observations: Another notable (M3.3) earthquake occurred last night at 10:20 pm. As has been common with these events, an associated rockfall generated a small ash plume that rose slightly above the rim of the volcano. After the event seismicity returned to the usual level of one small earthquake every 4 to 7 minutes.

2005 July 19

USGS Update 2005-Jul-19 09:45

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.

Recent observations: A M2.8 at 8:55pm yesterday caused a large rockfall that sent an ash plume about 2,000 feet above the rim of the volcano. The rockfall removed a large piece off the top of the growing dome, and it destroyed one of the seismometers in the crater. Seismicity returned to normal levels after the event. Although the forecast is for good weather, we are without helicopter support this week. At our next opportunity we will make visual observations and possibly deploy a new seismometer.

2005 July 18

USGS Earthquake Report

Magnitude 3.1 - MOUNT ST. HELENS AREA, WASHINGTON 2005 July 19 03:54:53 UTC

A minor earthquake occurred at 20:54:53 (PDT) on Monday, July 18, 2005. The magnitude 3.1 event has been located in the MOUNT ST. HELENS AREA, WASHINGTON.

News Report Update

  • 3.2 quake rattles volcano, causes ash plume 2005-Jul-17 15:49 from The Portland Oregonian

    VANCOUVER, Wash. (AP)— A 3.2-magnitude earthquake rumbled under Mount St. Helens this weekend, causing a rockfall that puffed an ash plume above the crater rim.

    That midday plume Saturday was followed by another just before dark that was visible from Vancouver, U.S. Geological Survey scientists reported Sunday from the Cascades Volcano Observatory.

  • Magnitude 3 earthquake rattles volcano 2005-Jul-15 11:29 from The Portland Oregonian

    MOUNT ST. HELENS NATIONAL MONUMENT, Wash. (AP) — A magnitude 3 earthquake rattled Mount St. Helens on Friday, triggering rockfall and sending an ash plume above the crater rim, the U.S. Geological Survey reported.

    The quake occurred at 5:22 a.m., the largest recorded at the volcano in several months. Its cause was not immediately known.

USGS Update 2005-Jul-18 08:45

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 over a sector extending eastwards to east-southeastwards of the volcano.

Recent observations: Following the M 3.2 earthquake on 07/16 seismicity returned to normal levels. The crater and new lava dome are clear this morning, and pictures from the Sugarbowl camera indicate that the dome is continuing to grow. Seismicity and ground-deformation data indicate that no significant changes have occurred in the level of activity over the last 24 hours.

2005 July 17

USGS Update 2005-Jul-17 08:00

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 over a sector extending from southeastwards to westwards of the volcano.

Recent observations: A M 3.2 occurred yesterday at 1:08 pm local time followed by a rockfall that put a small ash plume over the crater rim. Another rockfall at 9:10 pm yesterday evening produced a small ash plume that was visible from Vancouver and dissipated rapidly. With the steep-sided dome now standing hundreds of feet above the crater floor, frequent rockfalls are to be expected. Ash clouds resulting from these rockfalls may on occasion be large enough to reach above the crater rim. Such clouds rarely extend higher than 11,000' above sea level and dissipate relatively rapidly. The crater and new lava dome are clear this morning, and pictures from the Sugarbowl camera indicate that the dome is continuing to grow. Seismic and ground-deformation data indicate that no significant changes have occurred in the level of activity over the last 24 hours.

2005 July 16

USGS Update 2005-Jul-16 08:30

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 eastwards early and southeastwards later.

Recent observations: Following yesterday's M 3.1 event seismicity returned to normal levels. After several clear days clouds again obscure views of the crater this morning, but seismic and ground-deformation data indicate that no significant changes have occurred in the level of activity over the last 24 hours.

2005 July 15

USGS Update 2005-Jul-15 09:40

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 eastward to east-northeastward later.

Recent observations: An ~M3 earthquake at 5:22am triggered a rockfall that sent an ash plume above the rim. This is the largest quake that has occurred in some time, and its exact cause is under debate. Over the past two days, new GPS stations were deployed on the east and west arms of the glacier, along with a new seismic station on the west glacier. Measurements of CO2 and SO2 on Wednesday indicated that there has been little change in the amounts of gases emitted by the volcano. Thermal and conventional imagery show that maximum temperatures of the dome are about 660 C ( ~1200 F), and that a broad ridge along the west side of the dome continues to emerge. A digital elevation model (DEM) based on June photography should be completed soon, and photos for constructing another DEM were obtained on Wednesday. Overall, rates of seismicity and ground-deformation remain low while the dome continues to grow.

2005 July 14

USGS Update 2005-Jul-14 08:15

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.

Recent observations: Field crews had a busy and successful day yesterday retrieving and deploying new instrument packages in the crater, collecting rock samples, obtaining thermal imagery, measuring gases, and conducting GPS surveys on the volcano's flanks. Today, crews will be out retrieving and deploying more instruments and obtaining new photographs for making a digital elevation model. Rates of seismicity and ground-deformation remain low while the dome continues to grow.

2005 July 13

USGS Update 2005-Jul-13 08:50

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 early in the day and shift to more southeastward to eastward trajectories later.

Recent observations: A layer of low clouds continues to obscure views of the volcano, although glimpses from the remote camera at the crater mouth suggest the crater is mostly clear. If the clouds dissipate sufficiently today, some field crews may attempt to go out. Rates of seismicity and ground-deformation remain low even though camera images from late last week indicate that the dome continues to emerge at a rapid pace.

2005 July 12

USGS Update 2005-Jul-12 09:30

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 to east-northeastward.

Recent observations: The crater and growing lava dome remain mostly obscured by clouds this morning. We have not had a decent look at the dome since last Thursday. Rates of seismicity and ground-deformation have declined over the past two weeks and are now at some of the lowest levels since the eruption began. A similar lull in activity occurred in December, so it does not mean that the eruption is necessarily ending. Later this week, if weather allows, a full slate of field activity is planned. Crews will retrieve and deploy instrument packages in the crater, collect rock samples, obtain new photography, and conduct flights to measure gases and obtain thermal imagery.

2005 July 11

USGS Update 2005-Jul-11 09:30

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.

Recent observations: The crater and growing lava dome are again mostly obscured by clouds this morning. Seismic and ground-deformation data indicate that no significant changes have occurred in the level of activity over the past 24 hours, and brief glimpses of the dome a few days ago suggest there have been no significant changes in its shape.

2005 July 10

USGS Update 2005-Jul-10 08:45

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.

Recent observations: The crater and growing lava dome are completely obscured by clouds this morning, but seismic and ground-deformation data indicate that no significant changes have occurred in the level of activity over the past 24 hours.

2005 July 09

USGS Update 2005-Jul-09 08:45

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 to northeastward.

Recent observations: The crater and growing lava dome are mostly obscured by clouds this morning, but seismic and ground-deformation data indicate that no significant changes have occurred in the level of activity over the past 24 hours.

2005 July 08

USGS Update 2005-Jul-08 09:00

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 crater and growing lava dome are obscured by clouds this morning, but seismic and ground-deformation data indicate that no significant changes have occurred in the level of activity over the past 24 hours. Yesterday's planned gas-sensing flight and other field work were canceled due to cloudy conditions around the mountain, and the return of poor weather conditions today will force postponement of crater-based field work to next week.

2005 July 07

USGS Update 2005-Jul-07 09:15

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 to northeastward.

Recent observations: One clear view from the Sugar Bowl Domecam this morning shows evidence of continued lava-dome growth as well as continued crumbling by rockfall. Today's gas-sensing flight and other field work await improvement in weather conditions.

2005 July 06

USGS Update 2005-Jul-06 08:15

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 crater and growing lava dome are obscured by clouds this morning, but seismic and ground-deformation data indicate that no significant changes have occurred in the level of activity over the past 24 hours. Hopefully weather conditions will improve tomorrow and permit us to conduct field studies.

2005 July 05

USGS Update 2005-Jul-05 09:45

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 to northeastward.

Recent observations: No significant changes have occurred in seismicity, ground deformation, or dome features over the past day. Weather wise, Thursday is looking like the best day for field work this week. We're planning a gas-sensing flight, exchange of some GPS receivers, aerial-photographic mission, and installation of a tiltmeter on the old lava dome.

2005 July 04

USGS Update 2005-Jul-04 10:30

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 east-southeastward early in the day and eastward to east-northeastward later.

Recent observations: The crater and new lava dome are clear this morning. There have been no significant recent changes in levels of seismicity or ground deformation. Dome growth continues with numerous small rockfalls. The USFS VolcanoCam showed glow from the dome through most of the night with bright bursts at about 10 pm last night and 4 am this morning; neither were marked by especially large seismic signals.

2005 July 03

News Report Update

  • Lava dome falls into Mount St. Helens 2005-Jul-03 04:20 from The Portland Oregonian/Associated Press

    MOUNT ST. HELENS NATIONAL MONUMENT, Wash. (AP) — A large part of the growing lava dome on Mount St. Helens fell Saturday, sending an ash plume above the crater rim, the U.S. Geological Survey reported. A rock fall had caused what scientists called a “substantial seismic signal” and knocked the chunk off the lava dome. The volcano was relatively quiet for the rest of the day.

    The U.S. Geological Survey and the University of Washington have monitored the volcano closely since it rumbled back to life Sept. 23 with shuddering seismic activity that peaked above magnitude 3 as hot magma broke through rocks in its path.

USGS Update 2005-Jul-03 10:00

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 chiefly eastward to east-northeastward; however, this morning low-altitude ash clouds would also drift westward.

Recent observations: The crater and new lava dome are clear this morning. No additional large rockfalls have occurred from the growing lava dome since the one yesterday morning, although small ones occur often. Seismicity and ground deformation remain at levels typical of those of the past few weeks.

2005 July 02

USGS Update 2005-Jul-02 10:15

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.

Recent observations: A rockfall at 6:30 this morning from the growing lava dome removed a large piece of the top of the dome, produced an ash plume that rose above the crater rim (which triggered pilot reports), and generated a substantial seismic signal. Persistent smaller rockfalls from the growing lava dome are building talus aprons on the western and northeastern flanks of the dome. Otherwise, the volcano remains relatively quiet and there are no significant changes in seismicity or deformation.

2005 July 01

USGS Update 2005-Jul-01 10:15

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 east-northeastward.

Recent observations: Crews had a productive day in the field yesterday. A new seismic station was slung onto the southeastern part of the new lava dome and one new and one relocated GPS spider will provide better information on direction and rate of glacier movement. Several spiders were retrieved for repairs and will return to service soon. The summer deployment of broadband seismometers is now complete after seismologists installed 2 instruments, increasing the total number to 19. Scientists also sampled water from streams draining the crater for chemical analysis and made repairs to flow monitors and other instruments. Persistent rockfalls from the growing lava dome are building talus aprons on the western and northeastern flanks of the dome. The northeastern talus is advancing close to several important instrument sites, which will probably have to be moved soon.