Dr. Lassiter's research focus is on the application of isotope and trace element geochemistry to fundamental problems of the Earth's origin and evolution, including but not limited to: Structure and chemical evolution of the mantle and crust; Origin of mantle plumes and nature of plume/lithosphere interaction; Generation and segregation of magma; Origin and chemical evolution of continental lithosphere; Chemical fluxes in constructive and destructive tectonic environments. Current areas of interest include the role of crust and lithospheric mantle recycling in the generation of mantle chemical heterogeneity, the origin and distribution of water and other volatile elements in the Earth's interior, and the thermal and chemical evolution of the Earth's core and core/mantle boundary.

Areas of Expertise

Earth's origin and evolution, isotope and trace element geochemistry, the role of crust and lithospheric mantle recycling in the generation of mantle chemical heterogeneity, the origin and distribution of water and other volatile elements in the Earth's interior, and the thermal and chemical evolution of the Earth's core and core/mantle boundary


Research Locations



Postdoctoral Fellowship - National Science Foundation (1995 - 1997)

The Berkeley Fellowship - to be entered (1993 - 1995)

Graduate Research Fellowship - National Science Foundation (1990 - 1993)

Phi Beta Kappa Honor Society - Brown University (1989)

Sigma Xi Science Honor Society - Brown University (1989)

Associate Editor, Reviews of Geophysics (2002)

Member, American Geophysical Union

member, Geochemical Society

member, European Union of Geosciences

Graduate Students

Edward W Marshall, Ph.D., expected 2017 (Supervisor)
I am currently studying the Colorado Plateau lithospheric mantle (CPLM), via xenoliths samples from the ca. 25 Ma Navajo Volcanic Field. My approach uses stable and radiogenic isotopes, nominally anhydrous mineral water contents, and Platinum Group Element (PGE) concentrations in sulfides. My PhD breaks down into three interrelated projects: 1) the long term geochemical evolution of the CPLM starting in the Proterozoic, 2) the more recent hydration and metasomatic overprint, and 3) the behavior of PGE elements in the CPLM and their relationship with hydration and metasomatic processes. Analytical techniques that I am familiar with are laser fluorination analysis for oxygen isotopes, SIMS analysis of nominally anhydrous mineral water contents, clean lab chemical separation methods for analysis of the Rb-Sr, Sm-Nd, Lu-Hf and Re-Os radiogenic systems, laser ICP-MS analysis of trace elements, and electron microprobe analysis of major elements. Other interests and projects of mine are the geology of the Philadelphia area, Anorthosite genesis, and laser fluorination technique development.

Jing Yang, Ph.D., expected 2016 (Committee Member)
My Area of Expertise: Diamond Anvil Cells, Synchrotron X-ray Diffraction, Conventional X-ray Diffraction, Brillouin Light Spectroscopy, Impulsive Stimulated Light Scattering, Raman Spectroscopy, Scanning Electron Microscopy, Electron Probe Mircron-analyzer, Matlab Programming

Benjamin L Byerly (Supervisor)
I use the major element, trace element, and isotopic (Sr-Nd-Pb-Hf-Os) chemistry of abyssal peridotites and mantle xenoliths to understand the evolution of the lithospheric and asthenospheric mantle.


YearSemesterCourse
2016Fall GEO 394 Rsch In Geological Sciences
2016Spring GEO 394 Rsch In Geological Sciences
2016Spring GEO 303C Intro To The Solar System
2015Fall GEO 394 Rsch In Geological Sciences
2015Fall GEO 388T High-Temperature Geochemistry
2015Fall GEO 376T High-Temperature Geochemistry
2015Spring GEO 391 Earth In Deep Time
2015Spring GEO 303C Intro To The Solar System
2014Fall GEO 394 Rsch In Geochemistry
2014Spring GEO 394 Rsch In Geochemistry
2014Spring GEO 303C Intro To The Solar System