If you’re planning to go to Friday’s joint colloquium at UNSW and can either offer space in your car or would like to share a ride, please let me know:firstname.lastname@example.org. If you want to go early enough to join the Speaker for lunch, please meet me at the watchtower just inside the city Road entrance at 12:15 p.m. (unless someone volunteers their car we need to meet at a place where a taxi can find us). I can also arrange transport for anyone wishing to go to the algebra seminar and then across to the colloquium. Speaker: Prof. Herbert E Huppert, (DAMTP, Cambridge) Title: Fluid modelling of carbon dioxide sequestration. Date: Friday, 22 August 2008 Time: 2:00 pm Venue: RC-4082, The Red Centre, UNSW. Meet for lunch at 1 p.m. outside the Eastern entrance to the Red-Centre by the big fig. Abstract: Current global anthropogenic emissions of carbon dioxide are approximately 27 Gigatonnes annually. The influence of this green-house gas on climate has raised concern. A means of reducing environmental damage is to store carbon dioxide somewhere until well past the end of the fossil fuel era. Storage by injection of liquid, or supercritical, carbon dioxide into porous reservoir rocks, such as depleted oil and gas fields and regional saline aquifers, is being considered. The presentation will discuss the rate and form of propagation to be expected. It builds on theoretical and experimental investigations of input of liquid of one viscosity and density from a point source above an impermeable boundary, either horizontal or slanted, into a heterogeneous porous medium saturated with liquid of different viscosity and density. Key predictions are: 1) for constant supply the radius of carbon dioxide ponding below a horizontal impermeable barrier will increase as the square root of time; 2) at constant supply rate the central thickness of the carbon dioxide pond is invariant with time; 3) the radius is proportional to the quarter power of input flux and permeability; 4) the effect of a slope is unnoticed until a time scale which varies between months and years for typical natural parameters; and 5) it is possible to use measurements of radius to estimate volume stored. In the Sleipner natural gas field, carbon dioxide has been injected at a rate of ~ 1 Mt/yr since 1996. We will briefly show how to apply our results to interpret these field observations.