Fluid dynamical, geochemical and geomechanical aspects of geological CO2 storage
Event details
| Date | 24.05.2011 |
| Hour | 11:15 |
| Speaker | Marc Hesse, Assistant Professor, University of Texas at Austin, USA |
| Location |
ELA 1
|
| Category | Conferences - Seminars |
Geological CO2 storage raises many fundamental scientific questions and challenges our ability to simulate the long-term evolution and fate of the injected CO2. In my talk, I will discuss recent results and the ongoing work to answer the following questions: 1) How fast is CO2 dissolving into the brine? 2)Can geochemical field observations constrain the long-term convective dissolution rate? 3) Do surface deformation measurements provide a cost effective and real-time monitoring approach for geological CO2 storage?
The dissolution rate of CO2 is likely controlled by the presence or absence of convective currents induced by the increase in brine density with increasing CO2 saturation. I will present recent experimental, numerical and scaling results for the convective flux from a horizontal interface, and discuss possible opportunities to quantify CO2 dissolution rates from geochemical field data.
While convective currents have been observed in the lab and in numerical simulations the persistence of natural CO2 fields over geological periods of time suggests that convective dissolution may be limited in nature. Variations in noble gases and carbon isotopes in natural CO2 reservoirs suggest that large amounts of CO2 have dissolved, and lateral isotopic gradients may constrain the long-term CO2 dissolution rate. This requires the extension of our numerical simulations to include the isotopic fractionations occurring during two phase flow.
Finally, I will address how detailed observations of surface deformation may be assimilated into poroelastic models for coupled flow and deformation to improve predictions of the long-term CO2 migration. The unknown permeability structure of the storage formation contributes greatly to the uncertainty of our predictions. Repeated areal maps of changes in surface elevation provide valuable additional information that constrains the physical properties of the storage formation. Currently no systematic approach to the assimilation of this new data source is available. I will present first results from a poroelastic inverse model that can assimilate multiple types of data and will therefore greatly reduce the uncertainty in the permeability distribution in the storage formation.
Links
Practical information
- General public
- Free
Contact
- Christina Treier