Tectonic implications for uplift of the Transantarctic Mountains

• Main Authors: J. F. Lawrence, J. W. Van Wijk, N. W. Driscoll
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Antarctic; East Antarctica; Transantarctic Mountains; West Antarctica; Wilkes Subglacial Basin; Antarc*; Antarctica
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.605.7668

Summary The Transantarctic Mountains are a non-compressional mountain belt located on the tectonic boundary between cratonic East Antarctica and non-cratonic West Antarctica. Formation of this mountain belt and a possible relation with the West Antarctic Rift system are still debated. Here we suggest a new explanation for uplift of the mountains, formation of a small crustal root, depression of the hinterland Wilkes Basin and formation of the West Antarctic Rift system. Using thermo-mechanical models to study deformation of the tectonic boundary, we find that convergence of crustal material at the craton edge during extension results in formation of a small crustal root and uplift of the surface. Crustal material accumulates at the craton edge during extension because the cratonic lithosphere is too strong to deform. This explains the location of the mountains. We further suggest that the West Antarctic Rift system formed at the side of the craton because this is the weakest location in the region. The hinterland Wilkes Subglacial Basin is a flexural depression; thermo-mechanical models show that rifting does not occur in the hinterland as the craton is simply too strong. Our models thus suggest that uplift of the Transantarctic Mountains is related to formation of the West Antarctic Rift system and flexural depression of the Wilkes Basin. Citation: J. F. Lawrence, J. W. van Wijk and N. W. Driscoll (2007), Tectonic implications for uplift of the Transantarctic Mountains, in Antarctica: A Keystone in a Changing World – Online Proceedings of the 10th ISAES X, edited by A. K. Cooper and C. R. Raymond et al., USGS