Linda Elkins-Tanton and Group
Planetary formation and evolution
We are working on processes of chemistry and physics that control planetary evolution in the first tens of millions of years of the solar system, when planets are accreting, cooling, and developing their silicate mantle structure, their earliest crusts, and atmospheres formed by degassing the planetary interiors. By examining a range of possible bulk compositions as defined by primitive meteorites and applying a range of oxidizing or reducing conditions, we can predict a range of possible terrestrial planets, some pertinent to our solar system, and others appropriate for the unusual conditions of exoplanet systems.
We gratefully acknowledge the support of the NSF Astronomy program's CAREER grant, and NASA Mars Fundamental Research, LASER, and Lunar Institute programs.
Terrestrial planets and exoplanets: Magma ocean dynamics and early atmospheres
Planetesimals: Formation, heating, and differentiation
Mercury: Origin of core mass, mantle structure and composition, and crustal composition
Magma oceans on Earth: Implications for the earliest crust and the mantle before convection
The Moon and Earth: Tidal heating and timescales of solidification
The Siberian flood basalts and the end-Permian extinction
About 250 million years ago the largest continental flood basalts province, the Siberian flood basalts, and the largest extinction in the last 600 million years, the end-Permian extinction, seemed to occur simultaneously. We hope to demonstrate that the flood basalts triggered key environmental changes that lead to the severity of the extinction. Our team consists of about 30 scientists from 8 countries.
We are very grateful to the National Science Foundation's Continental Dynamics Program.
Please visit our project website: siberia.mit.edu
2010: The tuffs of the Kata and Angara river. Ben Black, Scott Simper, Seth Burgess, Anton, Volodia Pavlov, Lindy Elkins-Tanton, Sam Bowring. Roma Veselovskiy (photo: Scott Simper).
Magmatism and lithospheric dynamics
These projects address problems in lithospheric structure and dynamics. Our projects address processes of melting in the asthenosphere and the effects of melt on the lithosphere, including creating gravitational instabilities, lithospheric underplating, and compositional fertilization.
Magmatism on continents in the absence of subduction makes a fascinating study of process and mantle-lithosphere interaction. This magmatism can occur on a huge scale, as in the Siberian flood basalts, or in small-volume fields such as the Sierra Nevada.
Gravitational instabilities can produce melting both in the asthenosphere through which they fall, and in themselves, if they heat sufficiently quickly while sinking sufficiently slowly. We call this novel melting process "upside-down melting." These studies use finite element fluid flow codes, experimental petrology, and field work.
We gratefully acknowledge the support of the NSF Geophysics and Geology and Geochemistry programs, the NSF Continental Dynamics Program and the Jeptha H. (1945) and Emily V. Wade (1945) Funds.
The lithosphere-asthenosphere boundary - melt migration, densities, and viscosities
Magmatism in the Sierra Nevada
Upside-down melting and gravitational instabilities