Mount St. Helens Erupts Again: Activity from September 2004 through March 2005

Major, Jon J.; Scott, William E.; Driedger, Carolyn; Dzurisin, Dan

Abstract:

Eruptive activity at Mount St. Helens captured the world‘s attention in 1980 when the largest historical landslide on Earth and a powerful explosion reshaped the volcano, created its distinctive crater, and dramatically modified the surrounding landscape. Over the next 6 years, episodic extrusions of lava built a large dome in the crater. From 1987 to 2004, Mount St. Helens returned to a period of relative quiet, interrupted by occasional, short-lived seismic swarms that lasted minutes to days, by months-to-years long increases in background seismicity that probably reflected replenishment of magma deep underground, and by minor steam explosions as late as 1991. During this period a new glacier grew in the crater and wrapped around and partly buried the lava dome. Although the volcano was relatively quiet, scientists with the U.S. Geological Survey and University of Washington‘s Pacific Northwest Seismograph Network continued to closely monitor it for signs of renewed activity.

Genre:

USGS Numbered Series

ProdID:

75973

Citation Author:

Major, Jon J.; Scott, William E.; Driedger, Carolyn; Dzurisin, Dan

Citation Contributing Office:

USGS Cascades Volcano Observatory

Citation Datum:

Citation Day:

Citation Edition:

Citation Editor:

Citation End Page:

Citation Issue:

Citation Keywords:

Citation Language:

ENGLISH

Citation Larger Work Title:

Citation LatN:

Citation LatS:

Citation LonE:

Citation LonW:

Citation Month:

Citation No Pagination:

Citation Number Of Pages:

Citation Online Only Flag:

Citation Phsyical Description:

4 p.

Citation Projection:

Citation Public Comments:

Citation Publisher:

Citation Series:

Fact Sheet

Citation Series Code:

Citation Series Number:

2005-3036

Citation Search Results Text:

Mount St. Helens Erupts Again: Activity from September 2004 through March 2005; 2005; FS; 2005-3036; Major, Jon J.; Scott, William E.; Driedger, Carolyn; Dzurisin, Dan

Citation Start Page:

Citation Volume:

Citation Year:

2005

Type:

citation/reference

Text:

Mount St. Helens Erupts Again: Activity from September 2004 through March 2005; 2005; FS; 2005-3036; Major, Jon J.; Scott, William E.; Driedger, Carolyn; Dzurisin, Dan