Susan DeBari


Educational & Professional Experience

Ph.D. - Stanford 1990
B.A. - Cornell University 1984

Areas of Expertise

Geology:  Crustal scale petrologic processes within island arcs.  The focus is to understand the physical and chemical processes that operate within and beneath volcanic arc systems.  What processes govern magma generation in the mantle wedge? What happens to these magmas as they traverse the Moho into arc crust?  How does this arc crust become "continent-like"? This research takes the form of study of active arc systems as well as ancient systems. I am currently involved in three major research fronts: active Cascade volcanism, deep crustal sections of ancient volcanic arcs (Alaska, Vancouver Island, North Cascades Crystalline Core), and a marriage of the former fronts through a proposed research drilling expedition to the mid crust within the active Izu-Bonin volcanic arc of Japan.

Science Education:  Using results of research on student learning to develop curricular materials for undergraduate non-science majors that foster deep learning of science and scientific practices.

Courses Taught

  • GEOL 406 Igneous and Metamorphic Petrology (field and classroom versions)
  • GEOL 309 Volcanology
  • GEOL 423/523 Advanced Igneous Petrology
  • SCED 202 Transfer of Matter and Energy in Earth Systems
  • SCED 201 Transfer of Matter and Energy in Physical Systems
  • SCED 481 Fundamentals of Teaching Science

Recent M.S. Students

Cassandra King (in progress) - Volcanic Activity of the Izu-Bonin Rear-arc Since 2.8 Ma

Kim Wurth (2019) - Clinopyroxene trace element chemistry as a proxy for magma compositional variation in the Izu Bonin rear-arc over the last 14 million years. Read and download thesis here:

Luan Heywood (2018) - Diversity and petrogenesis of rhyolites from an intra-oceanic arc:  Evidence from IODP site U1437, Izu Bonin rear-arc and surrounding area. Read and download thesis here: and published here:

Rebecca Morris (Summer 2017) - Building Arc Crust – Plutonic to Volcanic Connections in an Extensional Island Arc, the Alisitos Arc Crustal Section (Southern Rosario Segment), Baja California. Read and download thesis here: and published here:

Ricardo Escobar (2016) - Mineral Complexities as Evidence for Open-System Processes in Formation of Intermediate Magmas of Mount Baker Volcanic Field, Northern Cascade Arc.  Read and download thesis here:

Mai Sas (2015) - High-Mg Andesites from the Northern Cascade Arc: Using Mineral Chemistry to Distinguish Between Hypotheses for Petrogenesis.  Read and download thesis here: and reprint of American Mineralogist paper here:

Christina Stout (2015) - High-Sr Volcanic Domes from the Lassen Volcanic Region, Southernmost Cascade Arc, Northern California: Implications for Andesite and Dacite Magma Generation. Read and download thesis here: 

Angela Cota (2014) - A geochemical study of the Riddle Peaks Gabbro, north Cascades: evidence for amphibole accumulation in the mid crust of an arc. Read and download thesis here:

Julie Gross (2012) - Felsic magmas from Mt. Baker in the northern Cascade arc: origin and role in andesite production. Read and download thesis here:

Steve Shaw (2011) - H2O contents in olivine-hosted melt inclusions from primitive magmas in the Northern Cascade Arc. Read and download thesis here:

Nicole Moore (2010) - Origin and geochemical evolution of mafic magmas from Mount Baker in the northern Cascade arc, Washington: probes into mantle and crustal processes. Read and download thesis here: and published here:

Troy Baggerman (2010) - The generation of a diverse suite of Late Pleistocene and Holocene basalt through dacite lavas from the northern Cascade arc at mount Baker, Washington. Read and download thesis here:  Published here:

Ben Paulson (2010) - Magmatic Processes in the Jurassic Bonanza Arc: Insights from the Alberni Region of Vancouver Island, Canada. Read and download thesis here:

Selected Awards & Honors

2016: Arlan Norman award for excellence in student mentoring