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Staff Directory

Director and State Geologist

Philip A. Pearthree, Ph.D.

  • Director
Quaternary mapping, seismicity, geologic hazards
  • 520-621-2444
pearthre@arizona.edu

Administrative Services

Randi Bellassai

  • Assistant Director, Business-Finance
Research administration, project management
  • 520-621-2432
rbellassai@arizona.edu

Gloria Cary

  • Administrative Assistant
  • 520-621-2470

Geoinformatics

Andrew Zaffos staff photo

Andrew Zaffos, Ph.D.

  • Chief of Geoinformatics
Paleobiology, Computer Science, Geography, Sequence Stratigraphy
  • 520-621-3635
azaffos@arizona.edu

Gary Hudman

  • Senior Research Scientist (Emeritus)
Systems Architecture
garyhudman@arizona.edu

Douglas Meredith, M.S.

  • Software Engineer
douglasm@arizona.edu

Haley-Mazzone Snellen

  • GIS Specialist II
hsnellen@arizona.edu

Leah Zaitlin

  • GIS Specialist
leahzaitlin@arizona.edu

Environmental Geology

Ann Youberg, Ph.D.

  • Chief of Environmental Geology
Landslides, post-wildfire debris flows
  • 520-621-2250
ayouberg@arizona.edu

Joseph P. Cook, M.S.

  • Research Scientist
Earth fissures, debris flows, Quaternary mapping
  • 520-621-2364
joecook@arizona.edu
Jeri Young

Jeri J. Young, Ph.D.

  • Research Scientist
Seismicity, Quaternary mapping
  • 520-621-2470
jeribenhorin@arizona.edu
Becky Beers

Rebecca Beers, M.S.

  • Research Scientist III
Geomorphology | Post-Wildfire Debris Flows | Geomorphic Hazards
rebeccabeers@arizona.edu
Chad at Wupatki National Monument, northern Arizona

Chad Kwiatkowski, M.S.

  • Research Scientist III
Geologic hazards, Quaternary geologic mapping, post-wildfire debris flows
chadjoseph@arizona.edu

Alexander B. Neely, Ph.D.

  • Research Scientist
Geomorphology, sediment transport, and field geology
abn5031@arizona.edu

Basin Analysis

Brian F. Gootee, M.S.

  • Chief of Basin Analysis
  • Tribal Liaison
Geologic mapping, basin analysis, geologic hazards, outreach
  • 520-621-2470
bgootee@arizona.edu

Lisa Thompson, M.S.

  • Research Scientist
Volcanology, GIS, Basin Analysis, Learning Design
  • 520-621-2470
lathompson@arizona.edu

Tawnya C. Wilson, M.S

  • Research Scientist
Subsurface characterization, basin analysis, CO2 and H2 geologic storage, sedimentology
  • 520-621-2470
tawnyawilson@arizona.edu

Mineral Resources & Bedrock Geology

Carson Richardson, Ph.D.

  • Chief, Mineral Resources & Bedrock Geology
Mineral deposits, structural geology, and regional geology
  • 520-621-2482
carichardson@arizona.edu
Brad Johnson

Brad Johnson, Ph.D.

  • Research Scientist
Bedrock mapping, structural geology, mineral deposits
  • 520-621-2470
bradjohnson@arizona.edu

Nathan Carey, M.S.

  • Research Scientist
economic geology, geochemistry, and petrology
  • 520-621-2470
ncarey@arizona.edu

Chong Ma, Ph.D.

  • Research Scientist
Structural geology, tectonics, geo/thermochronology, geochemistry
chongma@arizona.edu
Calvin Mako headshot

Calvin Mako, Ph.D.

  • Research Scientist
Structural Geology, Metamorphic Petrology, Tectonics, and Geochronology
cmako@arizona.edu

Zoey C. Plonka, M.S.

  • Research Scientist
Mineral deposits, geo/thermochronology, stratigraphy
  • 520-621-2470
zplonka@arizona.edu

Marcus Silva, M.S.

  • Research Scientist
Mine waste mapping and characterization, abandoned mine lands, mineral deposits and exploration
msilva01@arizona.edu

Mark E. Holland, Ph.D.

  • Research Scientist
Structural geology, tectonics, geochronology, and field geology
meholland@arizona.edu
  • About AZGS
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  • Ask a Geologist
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