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Durham University

Department of Geography

Staff Profile

Publication details for Professor Alexander Densmore

Densmore, A.L., Allen, P.A. & Simpson, G. Development and response of a coupled catchment fan system under changing tectonic and climatic forcing. Journal of Geophysical Research: Earth Surface. 2007;112:F01002.

Author(s) from Durham


Sediment fans are a potentially useful and underexploited recorder of Earth's climatic and tectonic history, but historical observations have led to conflicting views on the importance of tectonic, climatic, and lithologic variables in controlling fan morphology and deposition. A one-dimensional model of a sediment fan and its associated catchment is used to explore the sensitivity of such simple sediment routing systems to perturbations in fault slip and precipitation rates. A transport-limited catchment is coupled to a fan whose surface slope is set by the balance between catchment sediment efflux and the available tectonically generated basin accommodation. Rock uplift rate is spatially variable across the model space. Increasing the fault slip rate, or decreasing the precipitation rate, leads to an increase in fan slope, temporary back-stepping of the fan toe, and a pronounced angular unconformity. Conversely, a decrease in slip rate, or an increase in precipitation rate, results in a decrease in fan slope, and progradation and eventual stabilization of the fan toe. Once perturbed, the system evolves toward a new equilibrium state with time constants of ~0.5 to 2 Myr; these response times are insensitive to slip rate but are strongly dependent on precipitation rate. Variations in fan slope are well described by a dimensionless parameter that expresses equilibrium slope as a function of slip rate, precipitation rate, system size, and catchment lithology.
This parameter holds promise as a predictive tool in inverting the morphology of natural fans for environmental variables.


Allen, P. A. (2005), Striking a chord, Nature, 434, 961.
Allen, P. A. (2007), Time scales of tectonic landscapes and their sediment routing systems, in Earth's Dynamic Surface: Catastrophe and Continuity in Landscape Evolution, Geol. Soc. of London Spec. Publ., in press.
Allen, P. A., and A. L. Densmore (2000), Sediment flux from an uplifting fault block, Basin Res., 12, 367 380.
Allen, P. A., and N. Hovius (1998), Sediment supply from landslide-dominated
catchments: Implications for basin-margin fans, Basin Res., 10, 19 35.
Blair, T. C. (1999a), Sedimentary processes and facies of the waterlaid Anvil Spring Canyon alluvial fan, Death Valley, California, Sedimentology, 46, 913 940.
Blair, T. C. (1999b), Sedimentology of the debris flow-dominated Warm Spring Canyon alluvial fan, Death Valley, California, Sedimentology, 46, 941 965.
Blair, T. C., and J. G. McPherson (1994), Alluvial fan processes and forms, in Geomorphology of Desert Environments, edited by A. D. Abrahams and A. J. Parsons, pp. 354 402, CRC Press, Boca Raton, Fla.
Blair, T. C., and J. G. McPherson (1998), Recent debris-flow processes and resultant form and facies of the Dolomite alluvial fan, Owens Valley, California, J. Sediment. Res., 68, 800 818.
Bull, W. B. (1962), Relations of alluvial fan size and slope to drainage basin size and lithology in western Fresno County, California, Prof. Pap., 450- B, pp. 51 53, U.S. Geol. Surv., Washington D.C.
Bull, W. B. (1964), Geomorphology of segmented alluvial fans in western Fresno County, California, Prof. Pap., 352-E, 129 pp., U.S. Geol. Surv., Washington D.C.
Carretier, S., and F. Lucazeau (2005), How does alluvial sedimentation at range fronts modify the erosional dynamics of mountain catchments?, Basin Res., 17, 361 382.
Castelltort, S., and J. van den Driessche (2003), How plausible are highfrequency sediment supply-driven cycles in the stratigraphic record?, Sediment. Geol., 157, doi:10.1016/S0037-0738(03)00066-6.
Dade, W. B., and P. F. Friend (1998), Grain size, sediment transport regime, and channel slope in alluvial rivers, J. Geol., 106, 661 675.
Denny, C. S. (1965), Alluvial fans in the Death Valley region, California and Nevada, Prof. Pap., 466, 62 pp., U.S. Geol. Surv., Washington D.C.
Densmore, A. L., N. H. Dawers, S. Gupta, R. Guidon, and T. Goldin (2004), Footwall topographic development during continental extension, J. Geophys. Res., 109, F03001, doi:10.1029/2003JF000115.
Dorsey, R. J., P. J. Umhoefer, and P. D. Falk (1997), Earthquake clustering inferred from Pliocene Gilbert-type fan deltas in the Loreto basin, Baja California Sur, Mexico, Geology, 25, 679 682.
Du hnforth, M., A. L. Densmore, S. Ivy-Ochs, and P. A. Allen (2007), Timing of debris-flow fan aggradation and incision on Shepherd and Symmes Creek fans, Owens Valley, California, deduced from cosmogenic 10Be, J. Geophys. Res., doi:10.1029/2006JF000562, in press.
Fernandes, N. F., and W. E. Dietrich (1997), Hillslope evolution by diffusive
processes: The timescale for equilibrium adjustments, Water Resour.
Res., 33, 1307 1318.
Fraser, G. S., and P. G. DeCelles (1992), Geomorphic controls on sediment accumulation at margins of foreland basins, Basin Res., 4, 233 252.
Gordon, I., and P. L. Heller (1993), Evaluating major controls on basin stratigraphy, Pine Valley, Nevada: Implications for syntectonic deposition, Geol. Soc. Am. Bull., 105, 47 55.
Heller, P. L., C. L. Angevine, N. S. Winslow, and C. Paola (1988), Twophase stratigraphic model of foreland-basin sequences, Geology, 16, 501 504.
Hooke, R. L. (1967), Processes on arid-region alluvial fans, J. Geol., 75, 438 460.
Hooke, R. L. (1968), Steady-state relationships on arid-region alluvial fans in closed basins, Am. J. Sci., 266, 609 629.
Hooke, R. L., and W. L. Rohrer (1977), Relative erodibility of source-area rock types, as determined from second-order variations in alluvial fan size, Geol. Soc. Am. Bull., 88, 1177 1182.
Howard, A. D. (1980), Thresholds in river regimes, in Thresholds in Geomorphology, edited by D. R. Coates and J. D. Vitek, pp. 227 258, Allen and Unwin, St. Leonards, N.S.W., Australia.
Humphrey, N., and P. L. Heller (1995), Natural oscillations in coupled geomorphic systems: An alternative origin for cyclic sedimentation, Geology, 23, 499 502.
Hungr, O., S. McDougall, and M. Bovis (2005), Entrainment of material by debris flows, in Debris-flow Hazards and Related Phenomena, edited by M. Jakob and O. Hungr, pp. 135 158, Springer, New York.
Marr, J. G., J. B. Swenson, C. Paola, and V. R. Voller (2000), A twodiffusion model of fluvial stratigraphy in closed depositional basins, Basin Res., 12, 381 398.
Me tivier, F., and Y. Gaudemer (1999), Stability of output fluxes of large rivers in South and East Asia during the last 2 million years:
for floodplain processes, Basin Res., 11, 293 303.
Me tivier, F., Y. Gaudemer, P. Tapponier, and M. Klein (1999), Mass accumulation rates in Asia during the Cenozoic, Geophys. J. Int., 137, 280 318.
Milana, J. P., and L. Ruzycki (1999), Alluvial-fan slope as a function of sediment transport efficiency, J. Sediment. Res., 69, 553 562.
Mortimer, E., S. Gupta, and P. Cowie (2005), Nucleation and growth in coarse-grained deltas, Loreto Basin, Baja California Sur, Mexico: A response to episodic accelerations in fault displacement, Basin Res., 17, 337 359.
Oguchi, T., and H. Ohmori (1994), Analysis of relationships among alluvial fan area, source basin area, basin slope, and sediment yield, Z.
38, 405 420.
Paola, C., P. L. Heller, and C. L. Angevine (1992), The large-scale dynamics of grain size variation in alluvial basins: 1, Theory, Basin Res., 4, 73 90.
Parker, G., C. Paola, K. X. Whipple, and D. Mohrig (1998), Alluvial fans formed by channelized fluvial and sheet flow: 1, Theory, J. Hydraul.
Eng., 24, 985 995.
Pelletier, J. D. (2004), The influence of piedmont deposition on the time scale of mountain belt denudation, Geophys. Res. Lett., 31, L15502, doi:10.1029/2004GL020052.
Saito, K., and T. Oguchi (2005), Slope of alluvial fans in humid regions of Japan, Taiwan, and the Philippines, Geomorphology, 70, 147 162.
Simpson, G., and F. Schlunegger (2003), Topographic evolution and morphology of surfaces evolving in response to coupled fluvial and hillslope sediment transport, J. Geophys. Res., 108(B6), 2300, doi:10.1029/ 2002JB002162.
Smith, T. R., and F. P. Bretherton (1972), Stability and the conservation of mass in drainage basin evolution, Water Resour. Res., 8, 1506 1529.
Snyder, N. P., K. X. Whipple, G. E. Tucker, and D. J. Merritts (2000), Landscape response to tectonic forcing: Digital elevation model analysis of stream profiles in the Mendocino triple junction region, Northern California, Bull. Geol. Soc. Am., 112, 1250 1263.
Stein, R. S., and S. E. Barrientos (1985), Planar high-angle faulting in the Basin and Range: geodetic analysis of the 1983 Borah Peak, Idaho, earthquake, J. Geophys. Res., 90, 11,355 11,366.
Stock, J. D., K. M. Schmidt, and D. M. Miller (2004), Observations on alluvial fans with relevance to recent sediment transport, Eos Trans.
AGU, 85(47), Fall Meet. Suppl., Abstract H41G-03.
Sun, T., C. Paola, G. Parker, and P. Meakin (2002), Fluvial fan deltas:
Linking channel processes with large-scale morphodynamics, Water Resour.
Res., 38(9), 1151, doi:10.1029/2001WR000284.
Talling, P. J. (2000), Self-organization of river networks to threshold states, Water Resour. Res., 36, 1119 1128.
Talling, P. J., and M. J. Sowter (1998), Erosion, deposition, and basin-wide variations in stream power and bed shear stress, Basin Res., 10, 87 108.
Tucker, G. E., and K. X. Whipple (2002), Topographic outcomes predicted by stream erosion models: sensitivity analysis and intermodel comparison, J. Geophys. Res., 107(B9), 2179, doi:10.1029/2001JB000162.
van der Beek, P., and P. Bishop (2003), Cenozoic river profile development in the upper Lachlan catchment (SE Australia) as a test of quantitative fluvial incision models, J. Geophys. Res., 108(B6), 2309, doi:10.1029/ 2002JB002125.
Whipple, K. X. (2001), Fluvial landscape response time: how plausible is steady-state denudation?, Am. J. Sci., 301, 313 325.
Whipple, K. X. (2004), Bedrock rivers and the geomorphology of active orogens, Annu. Rev. Earth Planet. Sci., 32, 151 185.
Whipple, K. X., and T. Dunne (1992), The influence of debris-flow rheology on fan morphology, Owens Valley, California, Bull. Geol. Soc. Am., 104, 887 900.
Whipple, K. X., and C. R. Trayler (1996), Tectonic control of fan size:
The importance of spatially variable subsidence rates, Basin Res., 8, 351 366.
Whipple, K. X., and G. E. Tucker (1999), Dynamics of the stream power incision model: Implications for height limits of mountain ranges, landscape response time scales, and research needs, J. Geophys. Res., 104, 17,661 17,674.
Whipple, K. X., and G. E. Tucker (2002), Implications of sediment-fluxdependent river incision models for landscape evolution, J. Geophys.
Res., 107(B2), 2039, doi:10.1029/2000JB000044.
Willett, S. D., and M. T. Brandon (2002), On steady states in mountain belts, Geology, 30, 175 178.
Wobus, C., K. Whipple, E. Kirby, N. Snyder, J. Johnson, K. Spyropolou, B. T. Crosby, and D. Sheehan (2006), Tectonics from topography:
Procedures, promise, and pitfalls, in Tectonics, Climate, and Landscape Evolution, Geol. Soc. Am. Spec. Pap., 398, edited by S. D. Willett et al., pp. 55 74, Geol. Soc. of Am., Boulder, CO.
Zienkiewicz, O. C., and R. L. Taylor (2000), The Finite Element Method:
Volume 1, The Basis, 689 pp., Elsevier, New York.