Mr Guy Paxman
- 2015 - 2019: Ph.D. - 'Reconstructing the palaeotopography of Antarctica', Durham University.
- 2011 - 2015: MEarthSci - Earth Sciences, University of Oxford.
The Antarctic ice sheet has been present for ca. 34 million years (Ma). During and prior to this time, the landscape beneath the ice has been modified significantly by erosion, sedimentation, isostatic adjustment to loading/unloading, tectonic uplift and subsidence, and horizontal plate movements. Recent work has demonstrated that the behaviour of the ice sheet is highly sensitive to the topography; reconstructing the palaeotopography of Antarctica in the past is crucial for understanding ice sheet behaviour since at least 34 Ma.
My research is geared towards reconstructing regional Antarctic palaeotopography as far back as 100 Ma. In order to achieve this I am integrating a number of datasets, including geophysics (bedrock topography and potential fields), geomorphology, offshore sediment records, and ice surface conditions (e.g. elevation, velocity). I am focussing on large, recently-explored marine-based regions of the Antarctic ice sheet, where ice is grounded on bed that lies below sea-level. These areas include:
- The Recovery Catchment
- The Wilkes Subglacial Basin
- The Pensacola-Pole Basin
I am also interested in the linkages between mountain building, erosion, flexure, and ice sheet behaviour in mountain ranges such as the Gamburtsevs and Ellsworths.
My research aims to test a number of existing hypotheses for the topographic evolution of these regions, and in particular quantify the magnitude and distribution of erosion, sedimentation, elastic plate flexure, and tectonic deformation. Topographic reconstructions can then be fed into numerical ice sheet models, which can compare the behaviour of an ice sheet on the reconstructed topography compared to the modern topography. This work will help to understand key open questions, e.g. whether the ice sheet has become increasingly unstable as a result of landscape evolution processes; where and when ice first formed on Antarctica; and how we can reconcile records of past Antarctic (and global) temperature, ice volume and sea-level.
My research also aims to address some major open questions regarding intraplate mountain- and basin-forming processes and the role of erosion as a driver of isostatic uplift in temperate and polar climates.
This research will involve extensive collaboration with other IAPETUS partner institutions and the British Antarctic Survey (BAS).
- 2015 - 2019: 3.5 year NERC-funded studentship as part of the IAPETUS Doctoral Training Partnership (DTP).
- Paxman, G. J. G., Jamieson, S. S. R., Ferraccioli, F., Bentley, M. J., Ross, N., Armadillo, E., Gasson, E. G. W., Leitchenkov, G. & DeConto, R. M. Bedrock erosion surfaces record former East Antarctic Ice Sheet extent. Geophysical Research Letters. 2018;45:4114-4123.
- Paxman, G. J. G., Jamieson, S. S. R., Ferraccioli, F., Bentley, M. J., Forsberg, R., Ross, N., Watts, A. B., Corr, H. F. J. & Jordan, T. A. Uplift and tilting of the Shackleton Range in East Antarctica driven by glacial erosion and normal faulting. Journal of Geophysical Research: Solid Earth. 2017;122:2390-2408.
- Paxman, G. J. G., Watts, A. B., Ferraccioli, F., Jordan, T. A., Bell, R. E., Jamieson, S. S. R. & Finn, C. A. Erosion-driven uplift in the Gamburtsev Subglacial Mountains of East Antarctica. Earth and Planetary Science Letters. 2016;452:1-14.
- Paxman, G. J. G., Gregory, B. S., Payne, S. J., Forshaw, J. B., Brady, M. P., Khan, M. D., Avadanii, D., Wardle, G., Wills, J. J., Kovin, O. N., Naumova, O. B., Osovetskiy, B. M. & Naumov, V. A. Placer Gold Composition and Provenance Studies in the Kuznetskiy Alatau and Western Sayan, South-East Siberia: Results of Field Trip, Summer 2014. Bulletin of Perm State University: Geology. 2015;1:44-59.