Research drilling in young silicic volcanoes
Eichelberger JC. 1989. Research drilling in young silicic volcanoes. Scientific Drilling. 1(2):90-102
Magmatic activity, and particularly silicic magmatic activity, is the fundamental process by which continental crust forms and evolves. The transport of magma from deep crustal reservoirs to the surface is a neglected but important aspect of magmatic phenomena. It encompasses problems of eruptive behavior, hydrothermal circulation, and ore deposition, and must be understood in order to properly interpret deeper processes. Drilling provides a means for determining the relationship of shallow intrusive processes to eruption processes at young volcanoes where eruptions are best understood. Drilling also provides a means for directly observing the processes of heat and mass transfer by which recently emplaced intrusions approach equilibrium with their new environment. Drilling in the Inyo Chain, a 600-year-old chain of volcanic vents in California, has shown the close relationship of silicic eruption to shallow dike emplacement,the control of eruptive style by shallow porous-flow degassing, the origin of obsidian by welding, the development of igneous zonationby viscosity segregation, and the character and size of conduits in relation to well- understood magmatic and phreatic eruptions. Planned drilling at the site of the largest eruption of the century, in the Mt. Katmai region of Alaska, will test models for explosive eruptions, elucidate the process of vapor- transport of metals, and provide the first measurements of rates of cooling and chemical alteration in a relatively simple, non-composite igneous system.
- Type
- Journal Article
- Authors
- Eichelberger, J
- Units
- KATM
- Keywords
- Alaska, ashflows, Cooling, craters, Crystallization, degassing, Drilling, Emplacement, Eruptions, heat and mass transfer, Intrusions, Inyo Domes, Katmai National Park And Preserve, Long Valley Caldera, Magmas, Novarupta Lava Dome, Obsidian Dome, Rhyolites, siliceous composition, Valley Of Ten Thousand Smokes, Vents, volatiles, Volcanic Rocks, Volcanoes, Volcanology, Young Silicic Volcanoes