A volcanic eruption in the presence of ice or meltwater can be extremely hazardous, injecting huge amounts of ash into the atmosphere and generating catastrophic glacial outburst floods. But there is so much we can learn from volcano-ice interactions because they also create characteristic glaciovolcanic deposits that tell us about the environmental conditions during the eruption. Glaciovolcanic products have been found all over the world, most commonly in Iceland, Canada, and Antarctica, and even on Mars. By studying glaciovolcanic products, we can learn how to better prepare for hazards, whether there was water on Mars, and where ancient ice sheets used to be located.
I work with Dr. Ben Edwards (Dickinson College) on glaciovolcanic ridges in Iceland and British Columbia. Our research combines mapping, drone imagery and 3-D modeling, petrology, and many geochemical techniques, including the measurements of major and trace elements, isotopes, and gases. We focus primarily on transitions in eruptive style from explosive to gentle, magma transport systems beneath and within growing glaciovolcanic ridges, and the formation mechanisms of tephra deposits, intrusions, and pillow lavas.
Grants
Sherman Fairchild (Internal) – $9,700
Construction of Glaciovolcanic Pillow Ridges in Iceland; PI; 1-year, 3-student research project to study the geochemistry of Icelandic glaciovolcanism field sites (Summer 2019 – Spring 2020)
Luce Funds (Internal) – $7,000
Glaciovolcanism in British Columbia, Canada; PI; Support to conduct isotope analyses at UNC Chapel Hill TIMS lab (Spring 2016 – Summer 2017)
Keck Geology Consortium – $40,000
Constraints on Magma Transport and Eruption Dynamics at a Glaciovolcanic Pillow Ridge, Southwest Iceland; PI w/ Co-Director Ben Edwards (Dickinson College); 6-person REU project administered through Keck and Wooster (Summer 2016 – Spring 2017)
NSF-EAR Petrology and Geochemistry (NSF-EAR-1220176) – $126,905
Collaborative Research/RUI: Testing Hypotheses on Pillow Lava Production During Glaciovolcanic Eruptions; PI with Co-PI Ben Edwards (Dickinson College); 3-year, 6-student project to study subglacial pillows in Iceland and British Columbia (Summer 2012 – Summer 2016)
Publications
Pollock, M., B.R. Edwards, S. Hauksdóttir, *R. Alcorn, *L. Bowman, (2014). Geochemical and lithostratigraphic constraints on the formation of pillow-dominated tindars from Undirhlíðar quarry, Reykjanes Peninsula, Southwest Iceland, Lithos, 200-201, 317-333, doi:10.1016/j.lithos.2014.04.023.
Presentations
Grachen, H.M.*, Crawford-Muscat, S.*, Irving, W.R.*, Pollock, M., Edwards, B.R., Judge, S.A., Devereux, K.*, Banna, L.*, and Schaefer, M.*, (2019), A geochemical study of Bræðravirki (Western Volcanic Zone, Iceland) reveals regional glaciovolcanic variations and complex tinder construction: American Geophysical Union, V43G-0164.
Edwards, B.R., M. Pollock, (2018). Understanding the construction of pillow-dominated glaciovolcanic ridges, Abstract V23M-0219, presented at 2018 Fall Meeting, AGU, Washington, D.C., December 10-14.
Irving, W.R.*, B.R. Edwards, M. Pollock, *K.M. Sah, *R. Reynolds, *S.E. Crawford-Muscat, (2018). A glaciovolcanic origin for Bræðravirki ridge, Abstract V23M-0218, presented at 2018 Fall Meeting, AGU, Washington, D.C., December 10-14.
Pollock, M., B. Edwards, C. Wallace*, A. Hiatt*, S. Seaman, (2017). Multiple pillow-forming eruptions under changing water/ice conditions revealed in an ancient pillow-dominated tindar in southwest Iceland: IAVCEI 2017, Seattle, WA, Abstracts, p. 847.
Edwards, B., M. Pollock, W. Kochtitzky*, E. Was*, (2017). Constraints on the evolution of glaciovoclanic pillow-dominated tindars from Iceland and British Columbia, IAVCEI 2017, Seattle, WA, Abstracts, p. 293.
Heineman, R.*, M. Pollock, B. Edwards, F. Zeb Page, C. Lembo*, M. Orden*, C. Wallace*, (2017). Glaciovolcanic megapillows of Undirhlíðar, Reykjanes Peninsula, Southwestern Iceland: GSA Abstracts with Programs 49(6), doi: 10.1130/abs/2017am-301116.
Edwards, B.R., M. Pollock, W. Kochtitzy, C.-L. Engen*, (2016). 3-D Mapping of quarry walls to constrain the internal structure of a glaciovolcanic tindar, SW Iceland, GSA Abstracts with Programs 48(7), doi: 10.1130/abs/2016AM-287547.
Heineman, R.*, C. Lembo*, C-L. Engen*, W. Kochtitzy, C. Wallace*, M. Orden*, A. Thompson*, B. Kumpf*, B.R. Edwards, M. Pollock, (2016). New insights on the formation of glaciovolcanic tindar ridges from detailed mapping of Undirhlíðar Ridge, SW Iceland, GSA Abstracts with Programs 48(7), doi: 10.1130/abs/2016AM-286590.
Thompson, A.C.*, M. Orden*, C. Lembo*, C. Wallace*, B. Kumpf*, R. Heineman*, C-L. Engen*, B. Edwards, M. Pollock, W. Kochtitzy, (2016). Physical characteristics of glaciovolcanic pillow lavas from Undirhlíðar, SW Iceland, GSA Abstracts with Programs 48(7), doi:10.1130/abs/2016AM-286574.
Wallace, C.*, B. Kumpf*, R. Heineman*, C. Lembo*, M. Orden*, A. Thompson*, C-L. Engen*, W. Kochtitzy, M. Pollock, B. Edwards, A. Hiatt*, (2016). Geochemical constraints on the magmatic system and eruptive environment of a glaciovolcanic tindar ridge from Undirhlíðar, SW Iceland, GSA Abstracts with Programs 48(7), doi:10.1130/abs/2016AM-286588.
Reinthal, M.C.*, M. A. Pollock, A. Hiatt*, B.R. Edwards, S. Seaman (2016). Comparative study of volatiles in glaciovolcanic eruptions in Iceland and British Columbia, Canada, presented at 2016 VMSG Conference in Dublin, Ireland, 6-8 January.
*Francheschi, J.O’R.. *M. Reinthal, M. Pollock, B. Edwards, *E. Placenscia, and *W. Kochtitzy, (2014). Preliminary geochemical constraints on the evolution of Pillow Ridge Tindar, Edziza Volcanic Complex, NCVP, Geological Society of America Abstracts with Programs, 46, 6, 576.
*Silverstein, A., M. Pollock, B. Edwards, *A. Hiatt, *A. Perpalaj, and *M. Reinthal, (2014). Constraints on emplacement depths and eruption dynamics for pillow lavas from quarries in southwestern Iceland, Geological Society of America Abstracts with Programs, 46, 6, 576.
Edwards, B.R., *A. Perpalaj, M. Pollock, *A. Hiatt, *M. Reinthal, *A. Silverstein, *E. Was, *E. Plascencia, and S. Hauksdottir, (2014). Overview of the mineralogy and geochemistry of pillow lavas and dikes exposed at Vatnsskarð, Iceland: insights on physical and chemical processes at tindar ridges, Geophysical Research Abstracts, 16, EGU2014-15345, presented at EGU General Assembly 2014.
Edwards, B.R., M. Pollock, S. Hauksdottir, *A. Perpalaj, *A. Silverstein, *M. Reinthal, *E. Plascencia, *E. Was, *A. Hiatt, M.T. Gudmundsson, (2013). Along-axis variations in volcanology and geochemistry of a pillow-dominated tindar: Comparison of exposures in Undirhlíðar and Vatnsskarð quarries, Reykjanes Peninsula, Iceland, Abstract V41D-2839 presented at 2013 Fall Meeting, AGU, San Francisco, CA, 9-13 December.
*Hiatt, A., M. Pollock, B.R. Edwards, S. Hauksdottir, *M. Williams, *M. Reinthal, (2013) Estimated hydrostatic/cryostatic pressures during emplacement of pillow lavas at Undirhlíðar quarry, Reykjanes Peninsula, southwest Iceland, Abstract V41D-2840 presented at 2013 Fall Meeting, AGU, San Francisco, CA, 9-13 December.
Pollock, B.R. Edwards, S. Haukdsottir, *R. Alcorn, *L. Bowman, (2013). Dynamics of pillow-dominated subglacial eruptions recorded in Undirhlíðar quarry, Reykjanes Peninsula, southwest Iceland, IAVCEI 2013, 3H-O13.
Pollock, M., B.R. Edwards, *L. Bowman, *E. Was, *R. Alcorn, S. Hauksdottir, (2012). Can detailed mapping of subglacial pillow lavas inform our understanding of pillow-dominated submarine eruptions?, EOS Trans. AGU, Fall Meet. Suppl., Abstract V21A-2760.
*Bowman, L., M. Pollock, B. Edwards, *R. Alcorn, (2011). Geochemical and field relationships of pillow and dike units in a subglacial pillow ridge, Undirhlíðar quarry, southwest Iceland, GSA Abstracts with Programs, 43, 5, 102.
*Alcorn, R., M. Pollock, B. Edwards, (2011). Construction of subglacial pillow ridges: insights from compositional variations in a 3-D exposure, Undirhlíðar Quarry, Southwest Iceland, GSA Abstracts with Programs, Vol. 43, No. 1, p. 92.
*Alcorn, R., M. Pollock, and B.E. Edwards, (2010). A three dimensional exploration of subglacial pillow eruptions on the Sveifluhals Ridge in southwest Iceland, GSA Abstracts with Programs, Vol. 42, No. 5, p. 294.
I.S. Theses
Hannah Grachen (2020) Construction of Bræðravirki ridge, a sublglacial tindar in Western Iceland
Simon Crawford-Muscat (2019) Geochemistry and eruptive sequence of a sublglacial tindar, Bræðravirki ridge, Western Iceland
Ric Reynolds (2019) Palagonite alteration and stratigraphy on a subglacial tephra cone, Undirhlíðar ridge, southwest
Julia Franceschi (2016) Stratigraphy and geochemistry of Pillow Ridge, MEVC, British Columbia
Mary Reinthal (2016) Volatile contents of subglacial pillow lavas from Pillow Ridge, MEVC, British Columbia
Alex Hiatt (2015) Volatile contents of basaltic glasses from Undirhlíðar quarry, southwest Iceland
Leo Jones (2015) Petrography and Geochemistry of Xenoliths in Pillow Ridge, Mt. Edziza Volcanic Complex, British Columbia
Lindsey Bowman (2012) Geochemical and field relationships of pillow and dike units in a subglacial pillow ridge, Undirhlíðar quarry, southwest Iceland
Rebecca Alcorn (2011) A three-dimensional investigation of subglacial pillows, Reykjanes Peninsula, Iceland
Todd Spillman (2010) Relationship between pillow size and lava viscosity, Reykjanes Peninsula, Iceland
*undergraduate student