Charles G. Groat hosts Ask the White House

Thank you for joining us today. I am pleased to have the opportunity to answer questions about Mt. St. Helens, the most active volcano in the United States. While there hasn't been a full eruption, the activity over the past few weeks has made it clear that the volcano has awakened from its slumber. The steam and ash we have seen is likely to be followed by further activity as magma continues to move upward. While we don't expect anything as large and powerful as the 1980 eruption, some extrusion of molten material is likely. Right now the series of small earthquakes continues and there has been a small steam plume at times. Chip Groat

steve, from waukesha west high school writes:
now what my question is. when Mt saint helens was still with a top on did it really shoot its top off or did it discengrate?

When Mt. St. Helens erupted in 1980 the force was so powerful that it blew the upper part of one side of the mountain away. This destroyed much of the peak area and exposed the crater. Today you can see into the crater area through the huge gap in its side made by the eruption.

Mike, from Underwood, WA writes:
I have a house less than 50 miles from the volcano; what can I expect? Thanks for your time.

Our current opinion, based on the type of activity we are seeing, is that any eruption would not be large enough to affect areas nearly as extensive as the major eruption in 1980. If you are outside of that range or have high ridges or mountains between you and Mt. St. Helens, chances are the main thing you might experience is ash fall, if the wind were to be blowing in your direction during an eruption. Conditions can change, however, and you and others living in the general area should follow the news. We are holding briefings each day to keep the news media informed.

Bryan, from Milwaukie, Oregon writes:
I know Mt. St. Helens is quite active right now, as I found out up front and personal at noon on Oct. 1 at Windy Ridge and she has been certainly the center focus of attention lately. Is anyone keeping an eye on the more silent type of volcanoes like Mt. Rainier, Mt. Adams, and Mt. Hood, or perhaps the developing bulge in the Three Sisters area in Central Oregon?

Twenty eight volcanoes in the Pacific states and Wyoming have been active within the last 10,000 years. The ones you mentioned are among those and we are monitoring them. Three Sisters has been especially interesting and we have followed the bulging you mentioned with an exciting form of remote sensing called InSAR. It is taken from a satellite and allows us to measure changes in the elevation of the land surface of only a few centimeters. Mt. Ranier is also of special interest because of its closeness to heavily populated areas. There have been occasional very small earthquakes of the type commonly associated with volcanoes, but no signs of an impending eruption.

Sara, from California writes:
Dr. Groat,Thank you for your time today. Is Mount St. Helens the only active volcano in the United States? I know there are some in Hawaii, but are there any others in the Continental U.S.?

I find it interesting that Washington State has a volcano even though it seems tropical cultures (like Hawaii) are normally prone to them.

There are 172 volcanoes in the United States that have been active within the last 10,000 years. We consider that 70 of these would be a serious threat to life and property if they were to erupt again. Most of this group are in Alaska and Hawaii. Currently, three volcanoes in Alaska are showing signs of unrest. In Hawaii, Kilauea continues to erupt and activity at Mauna Loa suggests it is progressing toward eruption. Mt. St. Helens receives most of the attention because of its location and past history, however the others bear watching and we are monitoring them carefully. The location of volcanoes is related to the condition of the Earth's crust. The area in and surrounding the Pacific Ocean has crustal conditions that result in the formation of volcanoes which is why, as you mentioned, many volcanoes occur in places like Hawaii.

Travis, from St. Petersburg, Florida writes:
Do we still have to be concered about Mount St. Helen's today? It seems like it has cooled off a bit since last week and the news isn't reporting on it so much. Also--do we have to worry as much because it is only releasing steam right now?

Activity at Mt. St. Helens, including small earthquakes, steam and ash eruptions, and upward movement of magma, goes through different levels of intensity. People from the USGS and universities that study volcanoes have learned that we have to closely monitor these things as well as any gases being emitted, the rise and fall of the crater floor, and heat levels around the volcano to better understand what it might do next. While things are relatively quiet now, the rise of magma suggests that there is a good chance of further eruptions, but whether this will be over the next few days, months, or even years is not definite at this point.

Joanna, from Traverse City, MI writes:
Hi We were wondering how the BIG eruption of Mt. St. Helens that everyone is expecting to happen, would compare to the BIG BLAST of 1980? It would seem that since the big top of the mountain is gone, now, surely this wouldn't be as enormous, but maybe not. Thank-you for explaining to us all about Mt. St. Helens--it is an interesting subject

Based on the type and intensity of the activity we have been monitoring for the past few weeks, our scientists do not expect that any eruption stemming from what is currently occurring will be nearly as large as the big event of 1980. This sense of what is likely to happen could change if we see new patterns of activity, which is why it is so important to continually monitor volcanoes that show signs of life.

Adam, from New Orleans,LA writes:
Dear Director Groat, How is Mount St. Helen and because of the activeness of the volcano do you think that there may be an upcoming earthquake in the West Coast? I know it sounds broad, but I've heard from Discovery Channel (who has its own sources) that there may be an earthquake from the increasing erosion. Or is it really a matter of the plates underwater that could be the source of the volcano? Thank you Director Grant, Adam

Volcanoes in the Pacific Northwest, including Mt. St. Helens, and the major faults there and in California are related to the boundaries of the plates you mentioned, but one doesn't cause the other. The earthquakes we are measuring at the volcano are small and related to the movement of magma up into the volcano and are not the same type as the ones that occur along major faults and that cause large earthquakes. Because of this difference, the eruption of Mt. St. Helens will not cause earthquakes along the West Coast.

Bryan, from Tacoma, WA writes:
If indications of an eruption on the scale of the one in 1980 begin to show, what can be done to safeguard the public today considering what we've learned since then?

While, based on the present level of activity, we don't expect a large, destructive eruption from Mt. St. Helens, your question about safeguarding the public is an important one for those living near geologic features and process that affect life and property. Preparedness, based on understanding what the effects will be, is the key to avoiding loss of life and minimizing property damage. Earthquakes, landslides, volcanic eruptions, and land subsidence need continuing study to improve our understanding of how they operate, and regular monitoring to provide information to both scientists and the public. We have learned much more about volcano behavior since 1980, including about Mt. St. Helens. In the case of any future major eruption of Mt. St. Helens, this information will allow us to inform emergency response agencies and the news media so people can be evacuated from the projected areas of impact before the event occurs.

Dave, from Phoenix, AZ writes:
Is there any correlation to the recent earthquakes in California and the volcanic activity at Mount St. Helens ?

The volcanoes in the Cascade Range, including Mt. St. Helens, and the major faults in the West Coast area of the United States, both have a relationship to the boundaries of major crustal plates that continue to move. However the California earthquakes and the activity at Mt. St. Helens are not directly related, even though they are part of forces and heat generated along plate boundaries. So while we expect both of these features to be present, they do not cause each other.

Ken, from Mckinney, TX writes:
Over the last two weeks it seems a greater incidence of geologic events have been reported. Is this true and if so are we entering a period where more significant events can be expected? Thank You.

On a worldwide basis, the geologic events you noted, occur on a regular basis. The news media tend to focus on those that affect their audiences so we are hearing about Mt. St. Helens and the Parkdale earthquake in California. One creative person suggested that we should have a TV channel dedicated to reporting these events, something like the Discovery Channel. The frequency and worldwide distribution of volcanic eruptions, earthquakes, landslides, and other dramatic natural process remind us of how active our planet is.

Geoff, from Philadelphia, PA writes:
Director Groat,I was just wondering what tools are used to monitor Mount St. Helens and other volcanos. Is any of the data produced by these tools available to the public on the internet?

As technology has advanced, more and more tools for monitoring volcanoes have become available. We use seismometers to measure the small earthquakes associated with the movement of magma and fracturing of rocks. Global positioning system (GPS) instruments are used to measure the rise and fall of the sides and crater floor of Mt. St. Helens. Gas, is collected on the ground and from aircraft to provide information about the presence of fresh magma near the surface. Carbon dioxide, hydrogen sulfide, and sulfur dioxide are of particular interest. We use satellites, using a remote sensing tool known as InSAR, to measure the rise and fall of volcano slopes and craters. This is very useful because we don't have to put instruments on the ground and can observe many volcanoes on a regular basis. Information from some of these measurements is available at our web site http://volcanoes.usgs.gov.

Charles G. Groat
It has been a pleasure to answer your interesting questions about Mt. St. Helens. I hope you will log into our volcanoes web site at http://volcanoes.usgs.gov/ if you would like updates on Mt. St. Helens or information about the state of other U.S. volcanoes. Chip Groat