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Home  /  People  /  Francois Tissot

Francois Tissot

Professor of Geochemistry; Investigator, Heritage Medical Research Institute
Option Representative: Geochemistry; 
Diplôme d'Ingenieur, École National Supérieure de Géologie, 2009; M.Sc., Lulea University of Technology, 2009; Ph.D., University of Chicago, 2015. Visiting Associate, Caltech, 2017-18; Assistant Professor, 2018-24; Professor, 2024-; HMRI Investigator, 2021-.

Research Options

Geochemistry;  Geology; 

Research Areas

Extraterrestrial Geochemistry/Cosmochemistry;  Stable Isotope Geochemistry; 

Profile

My current research focuses on three broad problematics: (1) the formation and evolution of the Solar System, (2) the reconstruction of paleo-redox conditions in the ocean/atmosphere system, and (3) the potential of non-traditional stable isotopes for studying magmatic processes. These elemental and isotopic investigations are carried out by combining wet chemistry sample preparation in a clean laboratory environment, high-precision isotopic analyses on Multi-Collector Inductively Coupled Mass Spectrometer (or MC-ICPMS) ± Laser ablation, and interpretation of the data using physically based models.

Examples of research projects include, but are not limited to:

- understanding the origin of nucleosynthetic anomalies preserved in meteorites and planets
- understanding how chondrules (which make up to 80% of some meteorites) formed
- developing new isotope systematics to track magmatic, mantle, and crustal evolution and mixing
- constraining the redox state of the ocean throughout Earth's history, and in particular during the so-called "boring billion"
- finding ways to harness the current (and future) precision of isotopic measurements for medical applications.

I am always looking for motivated researchers at all levels (undergraduates, graduates students and postdoctoral scholars) with a strong background in basic science to work with and go after exciting geo- and cosmochemical questions. If you are interested in a position in my group, don't hesitate to contact me!

Publications

For a complete publications list, see feeds.library.caltech.edu
Ge 140 b. Radiogenic Isotope Geochemistry. 9 units (3-0-6); second term, 2023-24. An introduction to the principles and applications of radiogenic isotope systems in earth science, with emphasis on the applications of these systems, from dating to forensic. Topics to be covered include nucleosynthesis, radioactive decay phenomena, geochronology, geochronometry, isotopes as tracers of solar system and planetary evolution, extinct radioactivities, cosmogenic isotopes and forensic geochemistry. Taught in even years; alternates with Ge 140 a. Offered 2023-24.
Instructor: Tissot
Ge 219. Non-traditional Isotopes Seminar. 6 units (2-0-4); third term, 2023-24. Prerequisites: Ge 140 a or b, or permission of instructor. The course deals with advanced topics in stable and radiogenic isotope geo-/cosmochemistry and builds on Ge 140 a and b, with emphasis on non-traditional isotope systems (Mg, Fe, Ti, Mo, U, etc.). Starting with close examination of seminal papers, each topic will build up to a discussion of the remaining outstanding questions. Topics to be covered will be guided by class interests. Example subjects could include: the early solar system, nucleosynthetic anomalies, the early Earth, planetary differentiation, paleoredox reconstructions, medical use of stable isotopes. All participants will lead discussions of papers and present a lecture on a relevant subject. Grades will include participation, a review/proposal paper, and oral examination(s).
Instructor: Tissot
Ge 140 b. Radiogenic Isotope Geochemistry. 9 units (3-0-6); second term, 2022-23. An introduction to the principles and applications of radiogenic isotope systems in earth science, with emphasis on the applications of these systems, from dating to forensic. Topics to be covered include nucleosynthesis, radioactive decay phenomena, geochronology, geochronometry, isotopes as tracers of solar system and planetary evolution, extinct radioactivities, cosmogenic isotopes and forensic geochemistry. Taught in even years; alternates with Ge 140 a. Not offered 2022-23.
Instructor: Tissot
Ge 141. Isotope Cosmochemistry. 9 units (3-0-6); first term, 2022-23. Prerequisites: Instructor's permission. An introduction to the study of the origin, abundances and distribution of the elements and their isotopes in the Universe, with emphasis on the isotopic constraints into the conditions, events and processes that shaped our Solar System. Topics to be covered include: cosmology and the age of the Universe, the age of the Milky Way and the duration of nucleosynthesis, the fundamentals of isotopic fractionations, the key roles of isotopic anomalies in understanding Solar System dynamics, early Solar System chronology from short- and long-lived nuclei, chondritic meteorite components as clues to solar nebula and asteroid evolution, as well as planetary formation and chronology (e.g., Moon, Mars, Earth).
Instructor: Tissot
Ge 219. Non-traditional Isotopes Seminar. 6 units (2-0-4); third term, 2022-23. Prerequisites: Ge 140 a or b, or permission of instructor. The course deals with advanced topics in stable and radiogenic isotope geo-/cosmochemistry and builds on Ge 140 a and b, with emphasis on non-traditional isotope systems (Mg, Fe, Ti, Mo, U, etc.). Starting with close examination of seminal papers, each topic will build up to a discussion of the remaining outstanding questions. Topics to be covered will be guided by class interests. Example subjects could include: the early solar system, nucleosynthetic anomalies, the early Earth, planetary differentiation, paleoredox reconstructions, medical use of stable isotopes. All participants will lead discussions of papers and present a lecture on a relevant subject. Grades will include participation, a review/proposal paper, and oral examination(s).
Instructor: Tissot
Ge 140 b. Radiogenic Isotope Geochemistry. 9 units (3-0-6); second term, 2021-22. An introduction to the principles and applications of radiogenic isotope systems in earth science, with emphasis on the applications of these systems, from dating to forensic. Topics to be covered include nucleosynthesis, radioactive decay phenomena, geochronology, geochronometry, isotopes as tracers of solar system and planetary evolution, extinct radioactivities, cosmogenic isotopes and forensic geochemistry. Taught in even years; alternates with Ge 140a. Offered 2021-2022.
Instructor: Tissot
Ge 141. Isotope Cosmochemistry. 9 units (3-0-6); first term, 2021-22. Prerequisites: Instructor's permission. An introduction to the study of the origin, abundances and distribution of the elements and their isotopes in the Universe, with emphasis on the isotopic constraints into the conditions, events and processes that shaped our Solar System. Topics to be covered include: cosmology and the age of the Universe, the age of the Milky Way and the duration of nucleosynthesis, the fundamentals of isotopic fractionations, the key roles of isotopic anomalies in understanding Solar System dynamics, early Solar System chronology from short- and long-lived nuclei, chondritic meteorite components as clues to solar nebula and asteroid evolution, as well as planetary formation and chronology (e.g., Moon, Mars, Earth). Not offered 2021-2022.
Instructor: Tissot