Yunnan Province - Southeast Margin of the Tibetan Plateau

Debate about the largest continental plateau on Earth, the Tibetan plateau, is often framed in terms of two end member models: diffuse deformation and crustal thickening vs. discrete deformation and the importance of major strike-slip shear zones (England and Houseman, 1988 vs. Molnar and Tapponnier, 1975; Tapponnier et al., 1982). My thesis work on the southeast margin of the Tibetan Plateau demonstrated there is room for both models. Along the SE margin of the plateau, a major strike-slip fault, the Ailao Shan shear zone, was active until mid-Miocene time, accumulating significant displacement (Leloup et al., 1995; Harrison et al., 1996; Schoenbohm et al., 2005). Since Pliocene time, however, my work has shown that crustal thickening through lower crustal flow and diffuse surface deformation have been dominant, documented through geomorphic mapping and analysis of drainage networks (Clark and Royden, 2000; Clark et al., 2004; Schoenbohm et al., 2004; 2006a; 2006b), probably reflecting changes in the state of the crust that resulted from lower crustal flow. I demonstrated propagating uplift from NW to SE along the SE margin of the plateau, and quantified ~1400 m uplift along the Red River since Pliocene time or later, both of which I interpreted to reflect lower crustal flow.

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Clark, M.K., Royden, L.H., 2000, Geology, v. 28, p. 703-706.
Clark, M.K., Schoenbohm, L.M., Royden, L.H., Whipple, K.X., Burchfiel, B.C., Zhang, X., Wang, W., and Chen, L., 2004, Tectonics, v. 23, TC1006.
England, P.C., and Houseman, G.A., 1988, Phil Transactions Royal Society London, v. 326, p. 301-320.
Harrison, T.M., Leloup, P.H., Ryerson, F.J., Tapponier, P., Lacassin, R., and Chen, W.-J., 1996, in Yin A., and Harrison, T.M., eds., The Tectonic Evolution of Asia, Cambridge University Press, p. 208-226.
Leloup, P.H., Lacassin, R., Tapponnier, P., Schärer, U., Zhong, D., Liu, X., Zhang, L., Ji, S., and Phan, T.T., 1995, Tectonophysics, v. 251, p. 3-84.
Molnar, P., and Tapponnier, P., 1975, Science, v. 189, p. 419-426.
Schoenbohm, L.M., Whipple, K.X., Burchfiel, B.C., and Chen, L., 2004, GSA Bulletin, v. 116, p. 895-909.
Schoenbohm, L.M., Burchfiel, B.C., Chen, L.-Z., and Yin, J.-Y., 2005, Tectonics, v. 24, TC6015.
Schoenbohm, L.M., Burchfiel, B.C., Chen, L.-Z., and Yin, J.-Y., 2006a, GSA Bulletin, v. 118, p. 672-688.
Schoenbohm, Burchfiel, B.C., and Chen, L.-Z., 2006b, Geology, v. 34, p. 813-816.
Tapponnier, P., Peltzer, G., Le Dain, A.Y., Armijo, R., and Cobbold, P., 1982, Geology, v. 10, p. 611-616.