Search Results - "Vallance, James W."

Dynamics of seismogenic volcanic extrusion at Mount St Helens in 2004-05 by Gardner, Cynthia A, Qamar, Anthony I, Major, Jon J, Schilling, Steven P, Vallance, James W, Messerich, James A, Lisowski, Michael, LaHusen, Richard G, Iverson, Richard M, Malone, Stephen D, Pallister, John S, Dzurisin, Daniel, Moran, Seth C, Gerlach, Terrence M

“…The 2004-05 eruption of Mount St Helens exhibited sustained, near-equilibrium behaviour characterized by relatively steady extrusion of a solid dacite plug and…”
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Characteristics, extent and origin of hydrothermal alteration at Mount Rainier Volcano, Cascades Arc, USA: Implications for debris-flow hazards and mineral deposits by John, David A., Sisson, Thomas W., Breit, George N., Rye, Robert O., Vallance, James W.

“…Hydrothermal alteration at Mount Rainier waxed and waned over the 500,000-year episodic growth of the edifice. Hydrothermal minerals and their stable-isotope…”
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Advances in our understanding of pyroclastic current behavior from the 1980 eruption sequence of Mount St. Helens volcano (Washington), USA by Brand, Brittany D, Pollock, Nicholas, Vallance, James W, Ongaro, Tomaso Esposti, Roche, Olivier, Trolese, Matteo, Giordano, Guido, Marshall, Aaron A, Criswell, C William

“…This review summarizes what the volcanology community has learned thus far from studying the deposits of pyroclastic currents (PCs) from the 1980 eruption…”
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Catastrophic precipitation-triggered lahar at Casita volcano, Nicaragua: occurrence, bulking and transformation by Scott, Kevin M., Vallance, James W., Kerle, Norman, Luis Macías, Jose, Strauch, Wilfried, Devoli, Graziella

“…A catastrophic lahar began on 30 October 1998, as hurricane precipitation triggered a small flank collapse of Casita volcano, a complex and probably dormant…”
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Ash aggregate-rich pyroclastic density currents of the 431 CE Tierra Blanca Joven eruption, Ilopango caldera, El Salvador by Brown, Richard J., Van Eaton, Alexa R., Hernández, Walter, Condren, Pearce, Sweeney, Clare, Tournigand, Pierre-Yves, Vallance, James W.

“…The VEI 6, Tierra Blanca Joven pyroclastic sequence (30–90 km3 DRE volume), erupted from Ilopango caldera, El Salvador, in 431 CE, is the product of one of the…”
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A re-examination of the three most prominent Holocene tephra deposits in western Canada: Bridge River, Mount St. Helens Yn and Mazama by Jensen, Britta J.L., Beaudoin, Alwynne B., Clynne, Michael A., Harvey, Jordan, Vallance, James W.

“…Volcanic ash deposits (tephra) in western Canada are instrumental in providing independent chronologic control for many archaeological and paleoenvironmental…”
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A latest Pleistocene and Holocene composite tephrostratigraphic framework for northeastern North America by Jensen, Britta J.L., Davies, Lauren J., Nolan, Connor, Pyne-O’Donnell, Sean, Monteath, Alistair J., Ponomareva, Vera, Portnyagin, Maxim, Booth, Robert, Bursik, Marcus, Cook, Eliza, Plunkett, Gill, Vallance, James W., Luo, Yan, Cwynar, Les C., Hughes, Paul, Pearson, D. Graham

“…Lakes and bogs in northeastern North America preserve tephra deposits sourced from multiple volcanic systems in the Northern Hemisphere. However, most studies…”
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Surface morphology of caldera-forming eruption deposits revealed by lidar mapping of Crater Lake National Park, Oregon – Implications for deposition and surface modification by Robinson, Joel E., Bacon, Charles R., Major, Jon J., Wright, Heather M., Vallance, James W.

“…Large explosive eruptions of silicic magma can produce widespread pumice fall, extensive ignimbrite sheets, and collapse calderas. The surfaces of voluminous…”
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Edifice collapse and related hazards in Guatemala by Vallance, James W., Siebert, Lee, Rose, William I., Girón, Jorge Raul, Banks, Norman G.

“…Guatemalan volcanoes have at least seven debris-avalanche deposits, associated with Cerro Quemado, Fuego, Pacaya, Tecuamburro and an unidentified volcano. The…”
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