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Borehole observations of continuous strain and fluid pressure: Chapter 9

Strain is expansion, contraction, or distortion of the volcanic edifice and surrounding crust. As a result of magma movement, volcanoes may undergo enormous strain prior to and during eruption. Global Positioning System (GPS) observations can in principle be used to determine strain by taking the difference between two nearby observations and dividing by the distance between them. Two GPS stations
Authors
Evelyn A. Roeloffs, A. T. Linde

Explosive eruptive record in the Katmai region, Alaska Peninsula: An overview

At least 15 explosive eruptions from the Katmai cluster of volcanoes and another nine from other volcanoes on the Alaska Peninsula are preserved as tephra layers in syn- and post-glacial (Last Glacial Maximum) loess and soil sections in Katmai National Park, AK. About 400 tephra samples from 150 measured sections have been collected between Kaguyak volcano and Mount Martin and from Shelikof Strait
Authors
Judy Fierstein

Hydrothermal systems and volcano geochemistry

The upward intrusion of magma from deeper to shallower levels beneath volcanoes obviously plays an important role in their surface deformation. This chapter will examine less obvious roles that hydrothermal processes might play in volcanic deformation. Emphasis will be placed on the effect that the transition from brittle to plastic behavior of rocks is likely to have on magma degassing and hydrot
Authors
R.O. Fournier

Magmatic gas efflux at the Ukinrek Maars, Alaska

No abstract available.
Authors
Deborah Bergfeld, W. C. Evans, A.G. Hunt, R. G. McGimsey

Late pleistocene and holocene caldera-forming eruptions of Okmok Caldera, Aleutian Islands, Alaska

This chapter contains sections titled:IntroductionGeologic settingField and Analytical MethodsResultsDiscussionConclusions
Authors
Jessica F. Larsen, Christina A. Neal, Janet Schaefer, Jim Beget, Chris Nye

Strombolian explosive styles and source conditions

Forward Looking Infrared Radiometer (FLIR) cameras offer a unique view of explosive volcanism by providing an image of calibrated temperatures. In this study, 344 eruptive events at Stromboli volcano, Italy, were imaged in 2001–2004 with a FLIR camera operating at up to 30 Hz. The FLIR was effective at revealing both ash plumes and coarse ballistic scoria, and a wide range of eruption styles was r
Authors
Matthew R. Patrick, Andrew J. L. Harris, Maurizio Ripepe, Jonathan Dehn, David A. Rothery, Sonia Calvari

Volcano-electromagnetic effects

Volcano-electromagnetic effects—electromagnetic (EM) signals generated by volcanic activity—derive from a variety of physical processes. These include piezomagnetic effects, electrokinetic effects, fluid vaporization, thermal demagnetization/remagnetization, resistivity changes, thermochemical effects, magnetohydrodynamic effects, and blast-excited traveling ionospheric disturbances (TIDs). Identi
Authors
Malcolm J. S. Johnston

Volcano deformation--Geodetic monitoring techniques

This book describes the techniques used by volcanologists to successfully predict several recent volcanic eruptions by combining information from various scientific disciplines, including geodetic techniques. Many recent developments in the use of state-of-the-art and emerging techniques, including Global Positioning System and Synthetic Aperture Radar Interferometry, mean that most books on volca
Authors
Daniel Dzurisin, Zhong Lu

Ground-coupled acoustic airwaves from Mount St. Helens provide constraints on the May 18, 1980 eruption

The May 18, 1980 Mount St. Helens eruption perturbed the atmosphere and generated atmosphere-to-ground coupled airwaves, which were recorded on at least 35 seismometers operated by the Pacific Northwest Seismograph Network (PNSN). From 102 distinct travel time picks we identify coherent airwaves crossing Washington State primarily to the north and east of the volcano. The travel time curves provid
Authors
J.B. Johnson, S. D. Malone

Volcanic eruptions, hazards, and mitigation

No abstract available.
Authors
J. Feldman, R. I. Tilling

National volcanic ash operations plan for aviation

The National Aviation Weather Program Strategic Plan (1997) and the National Aviation Weather Initiatives (1999) both identified volcanic ash as a high-priority informational need to aviation services. The risk to aviation from airborne volcanic ash is known and includes degraded engine performance (including flameout), loss of visibility, failure of critical navigational and operational instrumen
Authors
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