Jump to navigation

The University of Arizona Wordmark Line Logo White
Home

 

 

FacebookTwitterYouTubeInstagramLinkedIn     Donate

Search form

  • Minerals
    • Mining in Arizona
    • King Copper
    • Gold Prospecting
    • Industrial Minerals
    • Mineral Rights
    • Mining Scams
    • Potash Case Study
    • Ask a Geologist
  • Publications
    • All Publications
    • Recent Publications
    • Document Repository
    • Map & Database Services
    • Geologic Report Index
    • Geologic Map Index
    • AZGS GeoBib Database
    • Photo Gallery
  • Center for Natural Hazards
    • All Natural Hazards
    • Earth Fissures & Ground Subsidence
    • Landslides & Debris Flows
    • Floods
    • Severe Weather
    • Problem Soils
    • Volcanism
    • Earthquakes
    • Radon
    • Homeowner's Guide
    • Ask a Geologist
    • Arizona Council on Earthquake Safety
  • Outreach & Geoheritage
    • Arizona Geoheritage
    • Educator Outreach
    • Public Resources
    • Ask a Geologist
    • Photo Gallery
  • Energy
    • Energy Resources
    • Geothermal
    • National Geothermal Data System
  • Basin Analysis
  • About
    • About AZGS
    • Projects
    • Events
    • News
    • Contact
    • Ask a Geologist
    • Staff
    • Services
    • Partners & Funders
    • Employment
  1. Home
  2. About

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

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

Ainsley Carling

  • Assistant Geologist (Student)

Katrina Im

  • Archivist (Student)

Chris Machado

  • Archivist (Student)

Rabia Qureshi

  • Archivist (Student)

Ibeth Ramirez

  • Archivist (Student)

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

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

Bridgett Holman

  • Archivist (Student)
  • About AZGS
  • Projects
  • Events
  • News
  • Contact
  • Ask a Geologist
  • Staff
  • Services
  • Partners & Funders
  • Employment

FacebookTwitterYouTubeInstagramLinkedIn

520.621.2352 | 1955 East 6th Street, P.O. Box 210184, Tucson, AZ 85721

The maps, reports, and other information and content on this website are provided as a public service for informational purposes only.  Accuracy is not guaranteed, and the information contained or linked on this website should not be relied on except as general information.  The University makes no warranties or representations of any kind, and specifically disclaims all warranties including the warranty of merchantability and fitness for a particular purpose.  Users are responsible for verification of all facts and information to their own satisfaction.

© 2025 The Arizona Board of Regents on behalf of The University of Arizona.