Staff and Postgraduate Students

Dr Alan Roberts, BA (Hons), MSci, PhD (Cantab), AMInstP

Post-Doctoral Research Asst. in the Department of Earth Sciences

Telephone: +44 (0) 191 33 42357

Room number: Rm 309

Contact Dr Alan Roberts (email at a.w.roberts@durham.ac.uk)

Biography

2008-present Research Associate; Dept. of Earth Sciences, University of Durham, UK
2006-2008 Research Associate; Bullard Laboratories, University of Cambridge, UK
2002-2006 PhD "Crustal Structure of the Faroes North Atlantic Margin from Wide Angle Seismic Data"; University of Cambridge, UK
(supervisor: Prof. R.S. White FRS)
2001-2002 Intern; WesternGeco, Gatwick, UK
1997-2001 BA (Hons), MSci Natural Sciences (Experimental and Theoretical Physics); University of Cambridge, UK

Carbon Dioxide Injection and Storage

Motivated by mitigating against global climate change, industry is strongly incentivised to store CO₂ from industrial processes underground. Depleted hydrocarbon reservoirs are considered good locations for CO₂ injection, due to the currrently existing infrastructure and geological structures suited for gas trapping.

To assess the feasibility of such injection, accurate modelling is needed of the fluid dynamical processes involved as CO₂ is injected into the porous depleted reservoir systems, and the potential risk, due to potential leakage and other sources.

Working with Prof. Jon Gluyas and Dr. Simon Mathias, and funded by Centrica, through simulation of the injection, mixing and shock processes and the development of new algorithms, to accurately model key fluid dynamical processes, Alan is seeking to generate insight into these processes in order to better inform policy makers and process design engineers.

Uncertainty characterisation and JIBA: Joint Inversion with Bayesian Analysis

Alan is interested in the question of modelling uncertainty in geophysical contexts and has been working with Dr. Richard Hobbs (Earth Sciences) and Prof. Michael Goldstein (Mathematics), along with collaborators in IFM-Geomar on the JIBA (Joint Inversion with Bayesian Analysis) project.

The aim has been to develop a workable scheme for the joint inversion of Gravity, MT and Seismic datasets using an emulator-based rapid model screening approach, which is Bayesian in character. The main advantage of a Bayesian approach over traditional deterministic techniques is that all sources of uncertainty, as well as all prior beliefs about the structure can be fully included in the 'inversion'.

The JIBA website can be found at:

http://www.ifm-geomar.de/index.php?id=jiba&L=1

As well as in the specifically geophysical context, Alan is also interested in the wider question of uncertainty treatment and public perception across science and other fields, and is working with PIs from Earth Sciences, Mathematics and Computer Sciences on developing inter-disciplinary proposals to address these questions.

iSIMM: integrated Seismic Imaging and Modelling of Margins

Prior to working in Durham Alan was based at the Bullard Laboratories, Cambridge, where he completed a PhD entitled "Crustal Structure of the Faroes North Atlantic Margin from Wide-Angle Seismic Data" and then continued as a post-doc working under Prof. Bob White. His work was part of the iSIMM (integrated Seismic Imaging and Modelling of Margins) programme, and was primarily focused on the construction and analysis of a 2D wide-angle velocity model of the Continent-Ocean Transition (COT) and surrounding continental basalt and sub-basalt structure. As well as exploring new ways of probing sub-basalt, the work resulted in important new conclusions about the nature of intruded material at the COT, results of which were published in Nature, March 2008.

Details of the iSIMM project can be found at: http://www.badleys.co.uk/isimm-public/

Analysing the uncertainty of the low velocity sub-basalt sediment/hyaloclastic structure on this profile provided personal motivation for work on Bayesian constraint.

Research Groups

Geophysics Research Group

Research Interests

Application of Bayesian methods to joint inversion
Carbon Dioxide sequestration
Emulation of complex model simulators
Enhanced hydrocarbon recovery
Travel-time tomography
Deep crustal seismic imaging
Hydrocarbon reservoir simulation
Theology & Philosophy of Science

Publications

Edited works: conference proceedings

White, R.S., Eccles, J.D. & Roberts, A.W. (2010). Constraints on volcanism, igneous intrusion and stretching on the Rockall-Faroe continental margin. 7th Petroleum Geology Conference, London, England, Geological Society of London.
Roberts, A.W., Hobbs, R.W., Goldstein, M., Moorkamp, M., Heincke, B. & Jegen, M. (2010). Emulation: A Bayesian tool for joint inversion. 80th Annual Meeting of the Society of Exploration Geophysicists, Denver, Colorado, USA.
Eccles, J. D., White, R. S., Christie, P. A. F., Roberts, A. W. & iSIMM Team (2009). Insight into sub-basalt lithology from wide angle converted shear wave analysis. Faroe Islands Exploration Conference: Proceedings of the 2nd Conference, Torshavn, Faroe Islands, Annales Societatis Scientiarum Faeroensis (Faroese Society of Sciences and Humanities).
Roberts, A. W., White, R. S., Lunnon, Z. C., Christie, P. A. F., Spitzer, R. & iSIMM Team (2005). Imaging Magmatic Rocks on the Faroes Margin. 6th Petroleum Geology Conference, London, England, Geological Society of London.
White, R. S., Spitzer, R., Christie, P. A. F., Roberts, A., Lunnon, Z., Maresh, J. & iSIMM Team (2005). Seismic imaging through basalt flows on the Faroes Shelf. Faroe Islands Exploration Conference: Proceedings of the 1st conference, Annales Societatis Scientiarum Faeroensis (Faroese Society of Sciences and Humanities), Torshavn, Faroe Islands..

Journal papers: academic

Roberts, A.W., Hobbs, R.W., Goldstein, M., Moorkamp, M., Jegen, M. & Heincke, B. (Submitted). Joint stochastic constraint of a large dataset from a salt-dome. Geophysics
Mathias, S.A. & Roberts, A.W. (2013). A Lambert W function solution for estimating sustainable injection rates for storage of CO2 in brine aquifers. International Journal of Greenhouse Gas Control
Roberts, A. W., Hobbs, R. W., Goldstein, M., Moorkamp, M., Jegen, M. & Heincke, B. (2012). Crustal constraint through complete model space screening for diverse geophysical datasets facilitated by emulation. Tectonophysics 572-573: 47-63.
Moorkamp, M., Heincke, B., Jegen, M., Roberts, A. & Hobbs, R. (2011). A framework for 3-D joint inversion of MT, gravity and seismic refraction data. Geophysical Journal International 184(1): 477–493.
Moorkamp, M., Jegen, M., Roberts, A. & Hobbs, R. (2010). Massively parallel forward modeling of scalar and tensor gravimetry data. Computers & Geosciences 36(5): 680-686.
Roberts, A. W., White, R. S. & Christie, P. A. F. (2009). Imaging igneous rocks on the North Atlantic rifted continental margin. Geophysical Journal International 179: 1024-1038.
White, R. S., Smith, L. K., Roberts, A. W., Christie, P. A. F., Kusznir, N. & Team, iSimm (2008). Lower-crustal intrusion on the north atlantic continental margin. Nature 452: 460-464.
Eccles, J. D., White, R. S., Roberts, A. W., Christie, P. A. F. & iSIMM Team (2007). Wide angle converted shear wave analysis of a North Atlantic volcanic rifted continental margin: constraint on sub-basalt lithology. First Break 25: 63-70.
Lunnon, Z., Roberts, A. W., Christie, P. A. F., White, R. S., Kusznir, N. & Roberts, A. (2002). Integrated seismic imaging and modelling of margins: an overview. Journal of Conference Abstracts 7: 138-139.
White, R. S., Christie, P. A. F., Kusznir, N. J., Roberts, A., Davies, A., Hurst, A. N., Lunnon, Z., Parkin, C. J., Roberts, A. W., Smith, L. K., Spitzer, R., Surendra, A. & Tymms, V. (2002). iSIMM pushes frontiers of marine seismic acquisition. First Break 20: 782-786.
Roberts, A. & Brown, L.M. (2001). Evolution of physics examining 1940-2000 at Cambridge. European Journal of Physics 22(4): 413-420.