Arc Volcanism

✦ Wizard Island in Crater Lake, Oregon, field work 2011. (photo: Steve Shirey)

Arc volcanism, the product of plate subduction in the oceans at island arcs and on the continents at continental margins, is a prime place on Earth where crust differentiates into more silicic compositions and is added to continental margins. It is a natural laboratory for the study of volcanic processes.

Relevant Publications

Ankney, M. E., Shirey, S. B., Hart, G. L., Bacon, C. R., & Johnson, C. M. (2016). Os and U–Th isotope signatures of arc magmatism near Mount Mazama, Crater Lake, Oregon. Earth and Planetary Science Letters, 437 IS -, 25–34.

Bybee, G.M., Ashwal, L.D., Shirey, S.B., Horan, M., Mock, T., and Andersen, T.B. (2014) Pyroxene megacrysts in Proterozoic anorthosites: Implications for tectonic setting, magma source and magmatic processes at the Moho: Earth And Planetary Science Letters, v. 389, 74–85.

Jicha, B.R., Johnson, C.M., Beard, B.L., Hart, G.L., Shirey, S.B., and Singer, B., 2009, Discriminating assimilants and decoupling deep- vs. shallow-level crystal records at Mount Adams using 238U–230Th disequilibria and Os isotopes: Earth and Planetary Science Letters, v. 277, p. 38-49.

Jicha, B.R., Hart, G.L., Johnson, C.M., Hildreth, W., Beard, B.L., Shirey, S.B., and Valley, J.W., 2009, Isotopic and trace element constraints on the petrogenesis of lavas from the Mount Adams volcanic field, Washington: Contributions to Mineralogy and Petrology, v. 157, p. 189-207.

Hart, G.L., Johnson, C.M., Hildreth, W., and Shirey, S.B., 2003, New Os isotope constraints on intra-crustal recycling of crustal domains with discrete ages: Geology, v. 31, p. 427-430.;2

Hart, G.L., Johnson, C.M., Shirey, S.B., and Clynne, M.A., 2002, Osmium isotope constraints on lower crustal recycling and pluton preservation at Lassen Volcanic Center, CA: Earth and Planetary Science Letters, v. 199, p. 269-285.

Brandon, A.D., Becker, H., Carlson, R.W., and Shirey, S.B., 1999, Isotopic constraints on time scales and mechanisms of slab material transport in the mantle wedge: evidence from the Simcoe mantle xenoliths, Washington, USA: Chemical Geology, v. 160, p. 387-407.

Brandon, A.D., Creaser, R.A., Shirey, S.B., and Carlson, R.W., 1996, Osmium recycling in subduction zones: Science, v. 272, p. 861-864.