|
|
 |
|||||||||||||||||
|
|||||||||||||||||
 |
|||||||||||||||||
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
2 Institute for Crustal Studies, University of California, Santa Barbara, California 93106, USA
1 Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
Despite intensive research into the coupling between tectonics and surface processes, our ability to obtain quantitative information on the rates of tectonic processes from topography remains limited due primarily to a dearth of data with which to test and calibrate process rate laws. Here we develop a simple theory for the impact of spatially variable rock-uplift rate on the concavity of bedrock river profiles. Application of the analysis to the Siwalik Hills of central Nepal demonstrates that systematic differences in the concavity of channels in this region match the predictions of a stream power incision model and depend on the position and direction of the channel relative to gradients in the vertical component of deformation rate across an active fault-bend fold. Furthermore, calibration of model parameters from channel profiles argued to be in steady state with the current climatic and tectonic regime indicates that (1) the ratio of exponents on channel drainage area and slope (m/n) is 
0.46, consistent with theoretical predictions; (2) the slope exponent is consistent with incision either linearly proportional to shear stress or unit stream power (n = 0.66 or n = 1, respectively); and (3) the coefficient of erosion is within the range of previously published estimates (mean K = 4.3 x 10–4 m0.2/yr). Application of these model parameters to other channels in the Siwalik Hills yields estimates of spatially variable erosion rates that mimic expected variations in rock-uplift rate across a fault-bend fold. Thus, the sensitivity of channel gradient to rock- uplift rate in this landscape allows us to derive quantitative estimates of spatial variations in erosion rate directly from topographic data.
Key Words: geomorphology • stream gradient • fluvial erosion • neotectonics • Siwalik Hills
This article has been cited by other articles:
|
|
 |
|
  P. A. Cowie, A. C. Whittaker, M. Attal, G. Roberts, G. E. Tucker, and A. Ganas New constraints on sediment-flux-dependent river incision: Implications for extracting tectonic signals from river profiles Geology, July 1, 2008; 36(7): 535 - 538. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N.F. Lane, A.B. Watts, and A.R. Farrant An analysis of Cotswold topography: insights into the landscape response to denudational isostasy Journal of the Geological Society, January 1, 2008; 165(1): 85 - 103. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. J. Finnegan, B. Hallet, D. R. Montgomery, P. K. Zeitler, J. O. Stone, A. M. Anders, and L. Yuping Coupling of rock uplift and river incision in the Namche Barwa Gyala Peri massif, Tibet Geological Society of America Bulletin, January 1, 2008; 120(1-2): 142 - 155. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. B. DeLong, J. D. Pelletier, and L. Arnold Bedrock landscape development modeling: Calibration using field study, geochronology, and digital elevation model analysis Geological Society of America Bulletin, January 1, 2007; 119(1-2): 157 - 173. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. F. Garcia Thresholds of strath genesis deduced from landscape response to stream piracy by pancho rico creek in the coast ranges of central california Am J Sci, October 1, 2006; 306(8): 655 - 681. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. R. Miller and R. L. Slingerland Topographic advection on fault-bend folds: Inheritance of valley positions and the formation of wind gaps Geology, September 1, 2006; 34(9): 769 - 772. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. T. Codilean, P. Bishop, and T. B. Hoey Surface process models and the links between tectonics and topography Progress in Physical Geography, July 1, 2006; 30(3): 307 - 333. [Abstract] [PDF]
|
|
|
|
|
|
A. D. Huerta and D. W. Rodgers Constraining rates of thrusting and erosion: Insights from kinematic thermal modeling Geology, July 1, 2006; 34(7): 541 - 544. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Wobus, K. X. Whipple, E. Kirby, N. Snyder, J. Johnson, K. Spyropolou, B. Crosby, and D. Sheehan Tectonics from topography: Procedures, promise, and pitfalls Geological Society of America Special Papers, January 1, 2006; 398(0): 55 - 74. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G.Y. Brocard and P.A. van der Beek Influence of incision rate, rock strength, and bedload supply on bedrock river gradients and valley-flat widths: Field-based evidence and calibrations from western Alpine rivers (southeast France) Geological Society of America Special Papers, January 1, 2006; 398(0): 101 - 126. [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]
|
|
|
|
|
|
M. A. Ellis and A. L. Densmore First-order topography over blind thrusts Geological Society of America Special Papers, January 1, 2006; 398(0): 251 - 266. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J.-L. Mugnier, D. Becel, and D. Granjeon Active tectonics in the Subandean belt inferred from the morphology of the Rio Pilcomayo (Bolivia) Geological Society of America Special Papers, January 1, 2006; 398(0): 353 - 369. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. E. Hilley and M. R. Strecker Processes of oscillatory basin filling and excavation in a tectonically active orogen: Quebrada del Toro Basin, NW Argentina Geological Society of America Bulletin, July 1, 2005; 117(7-8): 887 - 901. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. D. Stock, D. R. Montgomery, B. D. Collins, W. E. Dietrich, and L. Sklar Field measurements of incision rates following bedrock exposure: Implications for process controls on the long profiles of valleys cut by rivers and debris flows Geological Society of America Bulletin, January 1, 2005; 117(1-2): 174 - 194. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Molin, F. J. Pazzaglia, and F. Dramis Geomorphic expression of active tectonics in a rapidly-deforming forearc, Sila massif, Calabria, southern Italy Am J Sci, September 1, 2004; 304(7): 559 - 589. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
N. C. Mitchell Form of submarine erosion from confluences in Atlantic USA continental slope Canyons Am J Sci, September 1, 2004; 304(7): 590 - 611. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L.M. Schoenbohm, K.X Whipple, B.C. Burchfiel, and L. Chen Geomorphic constraints on surface uplift, exhumation, and plateau growth in the Red River region, Yunnan Province, China Geological Society of America Bulletin, July 1, 2004; 116(7-8): 895 - 909. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Huyghe, M. Foata, E. Deville, G. Mascle, and C. W. Group Channel profiles through the active thrust front of the southern Barbados prism Geology, May 1, 2004; 32(5): 429 - 432. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. W. Wobus, K. V. Hodges, and K. X. Whipple Has focused denudation sustained active thrusting at the Himalayan topographic front? Geology, October 1, 2003; 31(10): 861 - 864. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Spatial and Temporal Deformation along the Northern San Jacinto Fault, Southern California: Implications for Slip Rates Bulletin of the Seismological Society of America, October 1, 2002; 92(7): 2782 - 2802.
|
|
|
|
 |
|
 S. J. Jones Transverse rivers draining the Spanish Pyrenees: large scale patterns of sediment erosion and deposition Geological Society, London, Special Publications, January 1, 2002; 191(1): 171 - 185. [Abstract] [PDF]
|
|
|
|
|
|
L. S. Sklar and W. E. Dietrich Sediment and rock strength controls on river incision into bedrock Geology, December 1, 2001; 29(12): 1087 - 1090. [Abstract] [Full Text] [PDF]
|
|
| JOURNAL HOME | HELP | CONTACT PUBLISHER | SUBSCRIBE | ARCHIVE | SEARCH | TABLE OF CONTENTS |
