General Information:
About Us:
CU Boulder Webpages:

    Contact Information:

    Stephen ("Steve") J. Mojzsis

    Professor of Geology
    Director, Collaborative for Research in Origins (CRiO)
    Chair, Arts & Sciences Council
    Department of Geological Sciences
    University of Colorado at Boulder
    2200 Colorado Avenue
    Boulder, Co. 80309-0399
    office: 303-492-5014
    lab: 303-735-5021
    fax: 303-492-2606

    NEWS (click HERE for further information and bibliography):

    --> TWO of our Distinguished Alumni were highlighted in the December 2017 issue of ELEMENTS magazine!

  • Dustin Trail and Jennika Greer

    to Congratulations to Jennika (now a Ph.D. student at University of Chicago) for winning the Gordon McKay Award at the 80th MetSoc, and Dustin (Asst. Prof. at University of Rochester) for the 2017 Mineralogical Society of America (MSA) Award. We are *very* proud of their accomplishments.

  • Salutations and Huzzah! to Mike Zawaski (Ph.D. student in our group) who was awarded a Center for the Study of Origins Fellowship.

    RECENT WORK (check back for frequent updates):

  • Thermal effects of late accretion to the crust and mantle of Mercury Impact bombardment on Mercury in the solar system’s late accretion phase (ca. 4.4–3.8Ga) caused considerable mechanical, chemical and thermal reworking of its silicate reservoirs (crust and mantle). We use a 3D transient heating model to test the effects of two bombardment scenarios on early (pre-Tolstojan) Mercury’s mantle and crust. Results show that rare impacts by the largest (100km diameter) bodies deliver sufficient heat to the shallow mercurian mantle producing high-temperature ultra-magnesian (komatiitic s.s.) melts. We find that late accretion to Mercury induced volumetrically significant crustal melting (=58 vol.%), mantle heating and melt production, which, combined with extensive resurfacing (=100%), also explains why its oldest cratering record was effectively erased, consistent with crater-counting statistics.
  • Late accretion to the Moon recorded in zircon (U–Th)/He thermochronometry We conducted zircon (U–Th)/He (ZHe) analysis of lunar impact-melt breccia 14311 to detect low-temperature or short-lived impact events that have previously eluded traditional isotopic dating techniques. Our ZHe data record a coherent date vs. effective Uranium concentration (eU) trend characterized by >3500Ma dates from low (=75 ppm) eU zircon grains, and ca. 110Ma dates for high (=100 ppm) eU grains. Modeling shows that the data are most simply explained by impact events at ca. 3950Ma and ca. 110 Ma, and limits allowable temperatures of heating events between 3950–110 Ma. Our data show that zircon has the potential to retain 4He over immense timescales (=3950Myrs), thus providing a valuable new thermochronometer for probing the impact histories of lunar samples, and martian or asteroidal meteorites.
  • The cool and distant formation of Mars Mars’ formation requires a specific dynamical pathway, while this is less valid for Earth and Venus. We predict that Mars’ volatile budget is most likely different from Earth’s and that Venus formed close enough to our planet that it is expected to have a nearly identical composition from common building blocks.
  • A colossal impact enriched Mars' mantle with noble metals We show that Mars’ late accretion budget also requires a colossal impact, a plausible visible remnant of which is the emispheric dichotomy. The addition of sufficient HSEs to the Martian mantle entails an impactor of at least 1200 km in diameter to have struck Mars before ~4430 Ma, by which time crust formation was well underway. Thus, the dichotomy could be one of the oldest geophysical features of the Martian crust. Ejected debris could be the source material for its satellites.
  • Evaluating an impact origin for Mercury's high-magnesium region We find that an ~3000 km diameter impact basin easily exhumes Mg-rich mantle material but that the amount of subsequent modification required to hide basin structure is incompatible with the strength of the geochemical anomaly, which is also present in maps of Gamma Ray and Neutron Spectrometer data. Consequently, the high-Mg region is more likely to be the product of high-temperature volcanism sourced from a chemically heterogeneous mantle than the remains of a large impact event.

    GEOL 1020: Introduction to Geology 1 (some years)
    GEOL 1020: Historical Geology & Earth System History (next offered, Fall 2018)
    ASTR/GEOL 2040: Search for Life in the Universe (next offered, Spring 2018)
    GEOL 4500: Critical Thinking in Earth Sciences: Origin of Life (some years)
    GEOL 4130: Introduction to Planetary Field Geology (next offered Maymester, 2019)
    GEOL 4700/5700: Archean and Proterozoic Geology (some years)
    GEOL 4330/5330: Cosmochemistry (next offered, Spring 2019)
    ASTR/ATOC/GEOL 5835: Planetary Seminar (next offered Spring, 2018)
    GEOL 5700: Special Topics: Geobiology (this course is being remade and led by Profs. Kopf, Wing & Templeton)
    ASTR/GEOL 5130: Planetary Field Geology (next offered Spring, 2018 on the Big Island of Hawai'i)
    ASTR/GEOL 5800 Planetary Surfaces & Interiors (some years)
    ASTR/ATOC/GEOL 5830: Geology, Age and Origin of the Moon (some years)

[Ukalik site, September 2014]
  • Faculty Member

    Steve Mojzsis (email)

  • Staff Research Scientists

  • Graduate Students

    • Michael Zawaski - (B.Sc. Astronomy & Geology, CU; M.Sc. Earth Sciences, UNC), Ph.D. student since Fall 2016 (email)

  • Student Assistants and Researchers

    • Rayssa Martins-Pimentel (B.A. undergraduate student in Geology; PROJECT: Santa Fe impact structure)(email)

    • Amanda Alexander - (B.A. undergraduate student in Astronomy with a minor in Geology; PROJECT: Late Veneer contamination to Mars' crust)(email)

    • Ari Diddams (senior at Fairview High School, Boulder; PROJECT: Correlated compositions of stars with exoplanets)(email)

  • Our Distinguished Alumni

    • Jennika Greer (B.A./M.A. in Geology, now an NSF graduate fellow and Ph.D. student, University of Chicago, Department of Geophysical Sciences) (email)

    • Nicole Cates (Ph.D. in Geology; Research Faculty, University of Manitoba) (email)

    • Dr. Michelle Hopkins-Wilelicki (Ph.D. in Geology; Staff Associate, University of Alabama) (email)

    • Dr. Elizabeth Frank (Ph.D. in Geology; Science Director, Planetary Resources, Seattle, Washington) (email)

    • Dr. Oleg Abramov (former NAI NPP; Senior Scientist, Planetary Science Institute; Member of CRiO) (email)

    • Dr. Dominic Papineau (Ph.D. in Geology; Lecturer in geochemistry and astrobiology, University College London (UK)

    • Prof. Dustin Trail (M.A. in Geology; Assistant Professor, University of Rochester; Member of CRiO)

    • Prof. Elizabeth Swanner-Smith (Ph.D. in Geology; Assistant Professor, Iowa State University) (email)

    • Michael Gross B.Sc. undergraduate in Geology, now working with Prof. Julio Sepulveda (email)

    • Jon Adam M.Ed. in Science Education (Boulder Valley School District)

    • Steven Glaser M.Sc. in Geological Sciences (graduated Fall 2010; now Ph.D. student with E. Shock at ASU)

    • Laurie Carmack B.A. in Anthropology (M.Ed. student at University of Oregon)

    • Allison Schaiberger B.Sc. student in Geology (now a graduate student at the Colorado School of Mines)

    • Heather Sickels B.Sc. in Geology (freelance writer in Boulder, Colorado)

    • Kelsi Singer B.Sc. (honors) in Astrophysics/Archeaology/Geology; Ph.D. Washington University - St. Louis (now a posdoctoral researcher at the Southwest Research Institute, Boulder)

    • Nick Strohecker B.Sc. in Accounting, Minor in Geology (Robert Half International)

    • John Braswell B.Sc. in Geological Sciences at University of Michigan (2009 UNAVCO Summer Intern)

    • Diana Prado B.Sc. in Geological Sciences at University of Puerto Rico (2010 UNAVCO Summer Intern; now at Ferrovial Agroman S.A.)

    • Sarah Palaich (Ph.D. from UCLA, now back in Colorado doing Science Education)

    • Analisa Maier B.Sc., M.Sc. in Geological Sciences at University of Colorado (Staff Geologist, Apache Corporation, Midland, TX)

    • Ethan Putnam former high school honors student working in our lab, now at Dartmouth College(email)

    • Nick Warren B.Sc. in Geology (email)

    • Wilder Lavington B.Sc. undergraduate in Chemistry/Computer Science (email)

    • Cole Pazar B.Sc. undergraduate in Geology (now at Innovative Energy, Chegg Inc.) (email)

    • Jonathan Oulton (B.Sc. Geology, FSU), M.Sc. in Geological Sciences at the University of Colorado, now at Scarpa (email)

    • Jeff Jennings - (B.A. Physics, CU), M.Sc. in Astrophysics at LMU-Munich, Germany (email)

University of Colorado at Boulder
University of Colorado at Boulder

Department of Geological Sciences, University of Colorado
Department of Geological Sciences

Graduate Program in Planetary Sciences
Graduate Program in Planetary Sciences within the Department of Astrophysical and Planetary Sciences

The Center for Astrobiology at the University of Colorado
The Center for Astrobiology

Laboratory for Atmospheric and Space Physics at the University of Colorado
Laboratory for Atmospheric and Space Physics

CU Geophysics Program
Geophysics Program