Emily A. Hamecher
Ph.D. Candidate, Geology
California Institute of Technology
I am working with Paul Asimow and Mark Ghiorso on the development of a new thermodynamic model of mantle phase equilibria, xMELTS. Thermodynamic modeling of mineral solid solutions facilitates calculations of phase equilibrium in the Earth’s mantle. Mantle melting models include constraints from phase equilibria experiments, calorimetry, and crystal chemistry to indirectly explore mantle processes, as well as the physical properties of solid and liquid phases as a function of pressure, temperature, and composition. MELTS is a software package that models mantle melting. xMELTS extends the capabilities of MELTS to pressures and temperatures commensurate with those at the base of the transition zone in the Earth’s mantle. The goal is to create a model that reproduces phase relations for temperature and pressure conditions at depths from the shallow crust to the top of the lower mantle, for all compositions of natural magma and coexisting solids.
xMELTS will incorporate new activity-composition models for garnet and pyroxene solid solutions. We have recently completed a new comprehensive model of molar volumes of spinel solid solutions, and are currently developing a new molar volume model for garnet solid solutions, before moving on to the coupled-recalibration of the full thermodynamic models for garnet and pyroxene.
More information about the MELTS family can be found here.
My CV can be downloaded here.
Publications
Hamecher, E.A., Antoshechkina, P.M., Ghiorso, M.S., and Asimow, P.D. (In preparation) The molar volume of cubic garnets in the system SiO2-Al2O3-TiO2-Fe2O3-Cr2O3-FeO-MnO-MgO-CaO-Na2O.
Hamecher, E.A., Antoshechkina, P.M., Ghiorso, M.S., and Asimow, P.D. (2013) The molar volume of FeO-MgO-Fe2O3-Cr2O3-Al2O3-TiO2 spinels. Contributions to Mineralogy and Petrology, 165, p. 25-43, doi:10.1007/s00410-012-0790-0.
Jackson, J.M., Hamecher, E.A., and Sturhahn, W. (2009) Nuclear resonant X-ray spectroscopy of (Mg,Fe)SiO3 orthoenstatites. European Journal of Mineralogy, 21, p. 551-560.
Abstracts
Hamecher, E.A., Antoshechkina, P.M., Ghiorso, M.S., and Asimow, P.D. (2011) The molar volume of FeO-MgO-Fe2O3-Cr2O3-Al2O3-TiO2 spinels. Eos Trans. AGU, 92, Fall Meet. Suppl., Abstract V13G-08 (Oral presentation).
Hamecher, E.A., Antoshechkina, P.M., Ghiorso, M.S., and Asimow, P.D. (2009) Thermodynamic calibration of Cr-Al exchange equilibria for garnet and spinel. Eos Trans. AGU, 90, Fall Meet. Suppl., Abstract V13D-2056 (Poster presentation).
Hamecher, E.A., Sturhahn, W., and Jackson, J.M. (2008) Elasticity and sound velocities of (Mg,Fe)SiO3 orthopyroxenes determined by nuclear resonant inelastic X-ray scattering. Eos Trans. AGU, 89, Fall Meet. Suppl., Abstract MR53A-1701 (Poster presentation).
Teaching Experience
At Caltech:
Ge 215 Topics in Advanced Petrology: Interactive Lecture Course in Phase Equilibria (TA, Spring 2012)
Lectures, readings, seminars, and/or laboratory studies in igneous or metamorphic petrology, paragenesis, and petrogenesis. The course may cover experimental, computational, or analytical methods. Format and content are flexible according to the needs of the students. This year’s course was based on James B. Thompson’s GEOL 253 course taught at Harvard, c. 1975.
Ge 114a Mineralogy (TA, Fall 2010)
Atomic structure, composition, physical properties, occurrence, and identifying characteristics of the major mineral groups.
Ge 114b Optical Mineralogy Lab (TA, Fall 2010)
Additional laboratory studies of optical crystallography and the use of the petrographic microscope.
Ge 101 Introduction to Geology and Geochemistry (TA, Fall 2009)
A broad, high-level survey of geology and geochemistry with emphasis on quantitative understanding. Historical deduction in the geological and planetary sciences. Plate tectonics as a unifying theory of geology. Igneous and metamorphic processes, structural geology and geomorphology; weathering and sedimentary processes. Nucleosynthesis and chemical history of the solar system; distribution of the elements in the earth; isotopic systems as tracers and clocks; evolution of the biosphere; global geochemical and biogeochemical cycles; geochemical constraints on deep Earth structure.
Ge 212 Thermodynamics of Geological Systems (TA, Spring 2009)
Chemical thermodynamics as applied to geological and geochemical problems. Classical thermodynamics, including stability criteria, homogeneous and heterogeneous equilibria, equilibria subject to generalized constraints, equations of state, ideal and nonideal solutions, redox systems, and electrolyte conventions. Brief discussion of statistical foundations and an introduction to the thermodynamics of irreversible processes.