Geology Department
Prof. Frey

Holli Frey

Job Title
Professor of Geology
: F.W. Olin 315
Department/Program: Geology


B.A. 1999, Franklin Marshall College;
Ph.D. 2005 Geology, University of Michigan

Area of specialization:

Igneous petrology, volcanology, weathering of volcanic terrains

Field areas:

Oregon, Mexico, Maine, Dominica

Research interests

My research is focused on the evolution of volcanic and plutonic systems, phenocryst crystallization, and the weathering of volcanic terrains. I study the geochemical, geochronological, and physical aspects of continental magmatic systems at a variety of scales, from volcanic fields to individual phenocrysts. I am interested in how volcanic systems change over time and how that history is recorded in individual phenocrysts. I am also interested in how volcanic rocks break down and weather and their contribution to soil and watershed chemistry. My research is field based and uses a variety of analytical tools, including ICP-MS, EMPA, SEM, GIS, and 40Ar/39Ar geochronology.


Geology 112: Environmental Geology
Geology 117: Natural Disasters
Geology 220: Mineral Science
Geology 320: Origin of Igneous and Metamorphic Rocks
Geology 206: Volcanology
Geology 405: Senior Seminar


( * = students):

Frey, H.M., Szramek, K.J., Manon, M.R., and *Kissane, M.T. (2013) Slow weathering in a semiarid climate: changes in the mineralogy and geochemistry of subaerial lava flows in the Deschutes River Basin, central Oregon: Chemical Geology, v. 347, p. 135-152.
Frey, H.M., Lange, R.A., Hall, C.M., Nelson, S.A., Delgado-Granados, H., *Mastin, L., and *Wineberg, D.  (2013) 40Ar/39Ar geochronology of Volcán Tepetiltic, western Mexico: time scale for andesite cone construction and the climactic eruption of rhyolite-rhyodacite (in production, GSA Bulletin, doi:10.1130/B30790.1)
Frey, H.M., Manon, M.R.F., *Brehm, S., and *Flake, A. (2013) Monotonous crystal-rich dacitic ignimbrites from Dominica: Implications for magma recharge: Geological Society of America Abstracts with Programs, Vol. 45.
Frey, H.M., Manon, M.R.F., *Riehl, M., and *Kaminski, K. (2012) Generation of a zoned silicic pyroclastic deposit by partial melting of a sub-solidus magma chamber beneath Volcán Tepetitlic, Mexico: Geological Society of America Abstracts with Programs, Vol. 44.
Frey, H.M., Manon, M.R.F., *Delagdo, G., and *Willey, T. (2012) Field characterization of fine-grained lavas and volcanic tephras using portable x-ray fluorescence: Geological Society of America Abstracts with Programs, Vol. 44.
Lange RA, Frey HM, Hector J (2009) A thermodynamic model for the plagioclase-liquid hygrometer/thermometer. American Mineralogist, 94, 494-506.
Frey HM, Manon MRF (2009) Montserrat: The classroom to the field and back again. Geological Society of America Abstracts with Programs, Vol. 41, No. 7, p. 601
Crabtree S, Lange RA, Frey HM (2009) A Kinetic barrier to plagioclase nucleation in degassing andesite and dacite liquids during rapid ascent. Geological Society of America Abstracts with Programs, Vol. 41, No. 7, p. 416
Lange, R.A., Frey, H.M., Hall, C., Delgado-Granados, H., 2007, Evidence From a Crystal-Poor, Zoned (Rhyolite-Andesite) Pyroclastic Deposit From Volcan Tepetiltic, Western Mexico for Rapid Generation of Silicic Melt by Partial Melting of Granitoid and not by Segregation From a Long-Lived Crystal-Rich Mush, Eos Trans. AGU, 88 (52)

Academic Credentials

Ph.D., University of Michigan; B.A., Franklin & Marshall College;