Collaborative Research: CMG: Microstructural Controls on Transport Processes in Geophysical Systems

University Of Alaska Fairbanks Campus, Fairbanks AK

Investigators

Abstract

A combination of mathematical and numerical modeling, laboratory experiments, field experiments, and three-dimensional data visualization techniques will be applied to the problem of determining the influence of the microscale pore structure of sea-ice on the macroscopic thermodynamic and fluid transport properties of such ice. The work represents a collaboration between a mathematician, a glaciologist and a computer scientist. A variety of mathematical approaches, including both lattice and continuum percolation representations, to modeling the bulk properties of irregular three-dimensional media will be applied to ice with varying degrees of connectivity between microscale brine inclusions. Field and lab experiments, including MRI and X-ray imaging of ice samples, will be combined with modern three-dimensional rendering of the resulting data to provide quantitative and qualitative information about the variability of such connectivity, particularly as a function of ice temperature. Model predictions of macroscopic permeability and thermal conductivity will be compared to experimentally measured transport properties. Through a collaboration with Dr. J. Fry at Victoria University, New Zealand, and student research projects, the models developed for transport in sea-ice will be extended to fluid migration through rock and the diffusion of gas through glacial firn. The latter is an important factor in the interpretation of paleo-atmospheric composition from bubbles trapped in ice-cores. The project also includes a substantial amount of training and outreach, with field work for graduate and undergraduate students, and classroom demonstrations and experiments in elementary and secondary schools.