Flexural loading of the West Antarctic lithosphere

Southern McMurdo Sound, Antarctica, comprises eight distinctive volcanic centres in an impressive 150-km long archipelago of 5-km high volcanoes. The volcanoes decrease in age from early Miocene in the SE to recent in the NE and hence provide a unique opportunity to determine the flexural rigidity of the West Antarctic lithosphere within a temporal framework. The project will use magnetic, gravity and seismic survey data to determine the geometry of the volcanic massifs below the McMurdo Ice Shelf and their relationship to the sedimentary basins beneath southern McMurdo Sound, and use this data to determine the flexural rigidity of the West Antarctic lithosphere. Some of the data has already been collected and is available. Additional data will be collected in November-December, 2001. The project will involve data processing and computer modelling of magnetic and gravity data and combining this with existing seismic data. Project could involve fieldwork during November-December 2001 (to be negotiated).

Selected References

Behrendt, L.R., S.A. Henrys, J.B. Anderson, and P.J. Barrett, Patterns of late Cenozoic volcanic and tectonic activity in the West Antarctic rift system revealed by aeromagnetic surveys, Tectonics, 15, 660-676, 1996.

Fitzgerald, P.F., The Transantarctic Mountains of southern Victoria land: the application of apatite fission track analysis to a rift shoulder uplift, Tectonics, 11, 634-662, 1992.

Stern, T.A., and U.S. ten_brink, Flexural uplift of the Transantarctic Mountains, J. Geophys. Res., 94, 10,315-10,330, 1989.

Stern, T.A., F.J. Davey, and G. Delisle, Lithospheric flexure induced by the load of the Ross Archipelago, southern Victoria land, Antarctica, in Geological evolution of Antarctica, edited by M.R.A. Thomson, A. Crame, and J.W. Thomson, pp. 323-328, Cambridge University Press, 1991.

Sugden, D.E., G.H. Denton, and D.R. Marchant, Landscape evolution of the Dry Valleys, Transantarctic Mountains: tectonic implications, J. Geophys. Res., 100, 9949-9967, 1993.

ten Brink, U., and T. Stern, Rift Flank Uplifts and Hinterland basins: Comparison of the Transantarctic Mountains with the Great Escarpment of Southern Africa, J. Geophys. Res., 97, 569-585, 1992.