de Silva, Shanaka (Shan)
Professor
| Office: | 21 Dawes House |
| Phone: | 541.737.1212 |
| Fax: | 541.737.1200 |
| Email: | desilvas@geo.oregonstate.edu |
Volcanology
I use the volcanologists toolbox (Petrology, Geochemistry, Physical Volcanology, Geochronology, Remotely Sensed data, Geophysics) and collaborate with lots of smart people (like our VIPER group at OSU) to address volcanic problems that intrigue me. Most of the questions I address start in the field - nature is a mystery, volcanology rocks! Studies my students and I are currently working on emphasize magmatism and volcanism in volcanic arcs, Physical Volcanology and Petrology of Explosive Volcanic Eruptions, Caldera (super)volcanism and the volcano-plutonic connection, at all different scales from the global to micron-scale. Basically if something piques our interest, we find ways of addressing those issues. My philosophy for students is to explore interesting volcanic problems in the field and then use the volcanologists "toolbox" to solve those problems - an approach I call "Volcano Forensics" - a sort of CSI apporach to volcanic processes.
The broader impacts of our work relate to Volcanic hazards, Volcanism and Climate, and Earth Science Education and Outreach VolcanoWorld (http://volcano.oregonstate.edu). I am also committed to undergraduate research and Incearsing Diversity in the Earth Sciences (http://ides.oregonstate.edu).
I have recently formalized my interest in Planetary Geology by using the Puna of the Central Andes as an analog for Mars. Projects on the Medusae Fossae Formation on Mars and the Origin of Gravel Megripples are now underway.
Come and join the fun!
Education
B.Sc (Hons) Geology
University of Southampton, United Kingdom, 1982
PhD Earth Sciences
Open University, United Kingdom, 1987
Courses
GEO 305 - Living with Active Cascades Volcanoes (Winter term)
GEO 315 - Petrology (Winter 2009 only - sabbatical replacement)
GEO 427 - Introduction to Volcanology (Undergraduates) (Spring term)
GEO 527 - Volcanology (for Graduate Students) (Spring Term)
GEO 495 - Field Camp (Summer 2008, 2011)
GEO 295 - Intro to Field Geology (Fall 2011)
Recent Publications
Selected Papers from last Five Years (Student authors identified with #)
Salisbury, M.J#., Jicha, B.R., de Silva, S.L., Singer, B.S., Jimenez, N.C., and Ort, M.H., 2010. 40Ar/39Ar chronostratigraphy of Altiplano-Puna volcanic complex ignimbrites reveals the development of a major magmatic province. Geological Society of America Bulletin, doi:10.1130/B30280.1
de Silva, S.L., 2010. The largest wind ripples on Earth: COMMENT. Geology, v. 38, p. e218, doi:10.1130/G30780C.
Hora, J.M., Singer, B.S., Jicha, B.R., Beard, B.L., Johnson, C.M. de Silva, S.L., and Salisbury, M.J.#, 2010. Volcanic biotite-sanidine 40Ar/39Ar age discordances reflect partitioning and pre-eruption closure in biotite. Geology, v. 38; no. 10; p. 923–926; doi: 10.1130/G31064.1
de Silva, S.L., Bailey, J.E., Mandt, K.E.#, and J-G., Viramonte, 2010. Yardangs in terrestrial ignimbrites: Synergistic remote and field observations on Earth with applications to Mars. Planetary and Space Science, v. 58, Issue 4, p. 459-471
Lavallee, Y., de Silva, S. L., Salas, G., and Byrnes, J.M., 2009. Structural control on volcanism at the Ubinas, Huaynaputina, and Ticsani Volcanic Group (UHTVG), southern Peru Journal of Volcanology and Geothermal Research, v.186, p.253–264
Mandt, K.#, de Silva, S.L., Zimbleman, J., and Wyrick, D., 2009. Distinct erosional progressions in the Medusae Fossae Formation, Mars, indicate contrasting environmental conditions. Icarus, 204, Issue 2, , Pages 471-477
Mandt, K#., de Silva, S.L., Zimbleman, J., and Crown, D.A., 2008. The origin of the Medusae Fossae Formation, Mars: Insights from a synoptic approach. Journal of Geophysical Research (Planets) VOL. 113, E12011, doi:10.1029/2008JE003076..
Self, S., de Silva, S.L., and Cortes, J.A., 2008. Enigmatic clastogenic rhyolitic volcanism: the Corral de Coquena spatter ring, North Chile. Journal of Volcanology and Geothermal Research, v. 177, Issue 4, Pages 812-821. doi.org/10.1016/j.jvolgeores.2008.047.
de Silva, S.L., 2008. Arc magmatism, calderas, and supervolcanoes. Geology, v.36, no.8., p.671-672.
de Silva, S.L., Salas, G., and Schubring, S.#, 2008.Triggering Explosive Eruptions: The case for silicic magma recharge at Huaynaputina, southern Peru. Geology v. 36, p. 387-390.
Bachmann, O., Miller, C.F., de Silva, S.L., 2007. The volcanic-plutonic connection as a stage for understanding crustal magmatism. Journal of Volcanology and Geothermal Research. doi:10.1016/j.jvolgeores.2007.08.002. v. 167, p.1-23.
de Silva, S.L., and Gosnold, W.A., 2007. Episodic construction of batholiths: insights from the spatiotemporal development of an ignimbrite flare-up. Journal of Volcanology and Geothermal Research, v. 167, p.320-335. doi:10.1016/j.jvolgeores.2007.07.015
Lavallee, Y.#, de Silva, S.L., Salas, G., and Byrnes, J., 2006. Subsidence cessation during the initial stage of funnel caldera formation at Huaynaputina, southern Peru. Bulletin of Volcanology, v.68, No.4, p. 333-348.
Graduate Students
Current Graduate Students
Casey Tierney (Iowa State, MS), Timescales of silicic magmatic processes
Stephanie Grocke (Colby, PhD) Volatile constrains on superexplosive eruptions
Dale Burns (SDSU, Ph.D.), Evolution of continental magmatic system: insights from microanalysis Rodrigo Iriarte (Bolivia, PhD) The Cerro Guacha Caldera Complex
Jason Kaiser (UMass, Ph.D.), The Pastos Grandes Caldera Complex
Jamie Kern (MS/PhD) The Laguna Colorada Ignimbrite Shield
Recent Graduate Theses
Chris Harpel (Ph.D. 2010), Lahar sedimentology and hazards of the 2ka eruption of El Misti, southern Peru
Robert Peckyno (MS - 2010), Morphometric parameters of terrestrial lavas Mangon Abot (MS - 2010), Amphibole-Plagioclase P-T estimates for the Altiplano Puna Volcaninc Complex Kathy Mandt (MS - 2007) The origin and significance of the Medusa Fossae Formation, Mars
Peter Schoch (MS - 2006), Enhancing Undergraduate Physics Using Earth System Science Content
Shubhada Savant (MS - 2005), Volcano Spacing in the Central Andes : A GIS approach
Yan Lavallee (MS - 2004), Constraining Caldera formation processes at Volcan Huaynaputina, Southern Peru
Stephen Schubring (MS - 2001), Petrology and Geochemistry of Volcan Huaynaputina
Jason Permenter (MS - 2000), A GIS Approach to Volcanic Hazard Assessment in the Arequipa, Southern Peru
Nancy Adams (MS - 2000), Physical Volcanology of the 1600 eruption of Huaynaputina, Southern Peru
Where Former Advisees are Now
Chris Harpel, Earth Observatory of Singapore (Post-doc) Robert Peckyno, Multimedia Artist, Corvallis Kathy Mandt, SWRI San Antonio, Research Associate
Shubahada Savant, University of Illinois/NASA Stennis Space Center, Research Staff
Peter Schoch, Dean of Science, Sutton County Community College
Yan Lavallee, University of Munich, Assistant Professor
Steve Schubring, August Mack Environmental Inc, Indianapolis
Jan Lindsay, University of Auckland, New Zealand, Research Associate
Axel Schmitt, University of California, Los Angeles, Assistant Professor
Adam Dunne, Widener University, Department of Physics, Assistant Professor
Jason Permenter, Multimedia Artist, San Francisco
Nancy Adams, SWRI, San Antonio, Research Associate
Ken Copenhaver, NASA Stennis Space Center
Rob Watts, University of Puerto Rico, Mayaguez campus, Assistant Professor
Other Information
Important Collaborations
I am lucky to be working with an excellent young post-doc Trish Gregg. I wish I had her talent and energy.
The VIPER group at Oregon State is one of the leading groups focused on volcanological and magmatic processes in the world.