|
|
 |
|||||||||||||||||
|
|||||||||||||||||
 |
|||||||||||||||||
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
,1,1,1,2
1 Massachusetts Institute of Technology, Department of Earth, Atmospheric and Planetary Sciences, 77 Massachusetts Ave., Cambridge, Massachusetts 02139, USA
2 Yunnan Institute of Geological Sciences, 131 Baita Rd., Kunming, Yunnan, China
Field observations, digital elevation model (DEM) data, and longitudinal profile analysis reveal a perched low-relief upland landscape in the Red River region, Yunnan Province, China, which correlates to an uplifted, regional low-relief landscape preserved over the eastern margin of the Tibetan Plateau. As with other major rivers of the plateau margin, the Red River has deeply incised the low-relief upland landscape, which we interpret to be the remnants of a pre-uplift or relict landscape. We examine longitudinal river profiles for 97 tributaries of the Red River. Most profiles consist of three segments separated by sharp knickpoints: an upper, low-gradient channel segment, a steeper middle channel segment, and a very steep lower channel segment. Upper channel segments correspond to the relict landscape and have not yet experienced river incision. Steeper middle and lower segments indicate onset of rapid, two-phase river incision, on the basis of which changes in external forcings, such as climate or uplift, can be inferred. In terms of two end-member scenarios, two-phase incision could be the result of pulsed plateau growth, in which relatively slow uplift during the first phase is followed by rapid uplift during the second phase, or it could reflect adjustments of the main channel to changing climate conditions against the backdrop of steady plateau growth. Reconstruction of the paleo–Red River indicates 
1400 m river incision, 1400–1500 m surface uplift, and a maximum of 750 m vertical displacement across the northern Red River fault, elevating the northern Ailao Shan range above the surrounding relict landscape. On the basis of stratigraphic constraints, incision along the Red River likely began in Pliocene time.
Key Words: Asia • landscape evolution • Red River fault • Ailao Shan shear zone • erosion surface • fluvial geomorphology • incision
This article has been cited by other articles:
|
|
 |
|
  N. Harris Channel flow and the Himalayan-Tibetan orogen: a critical review Journal of the Geological Society, May 1, 2007; 164(3): 511 - 523. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. M. Schoenbohm, B. C. Burchfiel, and C. Liangzhong Propagation of surface uplift, lower crustal flow, and Cenozoic tectonics of the southeast margin of the Tibetan Plateau Geology, October 1, 2006; 34(10): 813 - 816. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Enkelmann, L. Ratschbacher, R. Jonckheere, R. Nestler, M. Fleischer, R. Gloaguen, B. R. Hacker, Y. Q. Zhang, and Y.-S. Ma Cenozoic exhumation and deformation of northeastern Tibet and the Qinling: Is Tibetan lower crustal flow diverging around the Sichuan Basin? Geological Society of America Bulletin, May 1, 2006; 118(5-6): 651 - 671. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. M. Schoenbohm, B. C. Burchfiel, C. Liangzhong, and Y. Jiyun Miocene to present activity along the Red River fault, China, in the context of continental extrusion, upper-crustal rotation, and lower-crustal flow Geological Society of America Bulletin, May 1, 2006; 118(5-6): 672 - 688. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. M. Gasparini, R. L. Bras, and K. X. Whipple Numerical modeling of non-steady-state river profile evolution using a sediment-flux-dependent incision model Geological Society of America Special Papers, January 1, 2006; 398(0): 127 - 141. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. V. Hodges A synthesis of the Channel Flow-Extrusion hypothesis as developed for the Himalayan-Tibetan orogenic system Geological Society, London, Special Publications, January 1, 2006; 268(1): 71 - 90. [Abstract] [PDF]
|
|
|
|
 |
|
 J. A. Spotila Applications of Low-Temperature Thermochronometry to Quantification of Recent Exhumation in Mountain Belts Reviews in Mineralogy and Geochemistry, January 1, 2005; 58(1): 449 - 466. [Full Text] [PDF]
|
|
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
