Prof. Herbert E Huppert
Institute of Theoretical Geophysics, University of Cambridge & Faculty of Science, Universities of Bristol and New South Wales
Current global anthropogenic emissions of carbon dioxide are approximately 32 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 and quantify some of the risks involved. The talk 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. 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. One of the best controlled field experiments, the Otway Project, commenced on 2 April 2008 in Victoria, Australia. Approximately sixty thousand tonnes of carbon dioxide was injected into a slanted sill over a period of just over a year. We will show how accurately some of our theoretical models predict the field data obtained so far. The talk will be illustrated by colour movie sequences of laboratory experiments and some simple desk-top demonstrations of aspects of flow of multi-phase fluids into a porous ambient.