Colorado
River near, Moab, UT ; photograph by Robert Cress
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GEOG 5251: FLUVIAL
GEOMORPHOLOGY
Lecture:
Tues/Thurs 11:00-12:15 PM
Lab: Tues 1:00-3:50
PM
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OVERVIEW
The goal of this course is to develop a detailed understanding of the
processes that govern the function and form of rivers. Rivers
adjust their characteristics over time and space to convey whatever
quantities of water and sediment are supplied from the watershed.
Assuming these quantities are known-- and often they are not-- the job
becomes one of predicting the spatial-temporal evolution of the channel
in response to changes in these inputs. Rarely is this possible
because rivers can develop different characteristics to accommodate the
same inputs of water and sediment; thus, there isn't a general solution
to the problem of river morphology. We can, however, make some
simplifying assumptions, or we can use robust empirical relations, to
develop predictive models of river behavior. Furthermore, given
that rivers are dynamic over human time scales, we can make field
measurements to test theoretical models. That's where the fun
begins. Topics to be covered in this course are as follows:
1. Basic fluid mechanics and flow in
natural channels
2. Sediment transport
3. Hydraulic geometry
4. Channel morphology (development of
bars; braided & meandering rivers)
5. Sediment sorting and development of
the longitudinal profile
6. Drainage basins, sediment yield, and
landscape evolution
We will spend about three weeks on each topic, although this will
vary. I will lecture most of the time; however, periodically we will
have short, discussion oriented sessions focusing on assigned readings
(listed below). We will also take several field trips and collect data
that will be used to test specific hypothesis or theories for river
behavior. In teaching the course, I assume that everyone has been
exposed to the basics of hydrology and geomorphology in upper division
courses in Geography or Geology, and that you are reasonably proficient
in math and physics. Lectures and discussions will be drawn from papers
on the attached reading list, supplemented by information in the
following textbooks:
Knighton, D., 1998, Fluvial Forms and
Processes, Arnold, New York, 383 pp.
Dingman, S.L., 1984, Fluvial Hydrology,
W.H. Freeman, New York, 383 pp.
I have put these books on reserve in the Geology Library. Copies of
the readings will be distributed in class.
Grading: There are no exams in this course. Grades will be based on
your scores on homework and lab exercises (30%), written critiques of
the readings (20%), and a 10-page term paper / field project (50%). My
expectations regarding the latter two components are as follows:
1. Readings: For several of the above topics I will assign a group
of papers; you will read these and summarize your thoughts in a 3-page
critique. The purpose of the written critiques is to get you to (a)
read the literature, (b) become critical of other people's work, and
(c) learn to write concisely. We will discuss the papers as a
group when the time arises.
2. Field Project: Half of your grade will be based on a field
project. The purpose of the field project is for you to get some
experience doing research. I expect that you will spend a minimum of
2-3 days in the field, and 2-3 days preparing the final report. I will
provide suggestions for possible projects and show you some examples of
good projects that people have done in the past. The field project must
be related to fluvial geomorphology- no snow and ice stuff, and no
canned data sets. Successful completion of this part of the course
requires careful time management; if you leave the project until the
last minute, you will not receive a high grade. The course will
conclude with student presentations of their field projects.
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Roaring
River, RMNP, Colorado
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Rees River, near Queenstown, NZ
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Flume at St. Anthony Falls Lab
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Hoffstad Creek, near Mt. St.
Helens, WA
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GEOG 5251 Fluvial
Geomorphology Reading List
1. Fluid Mecahnics and Open Channel Flow
No required reading; we will do several
exercises associated with field data collection. Papers of potential
interest:
Nelson, J.M., J.P. Bennett, and S.M. Wiele, 2003, Flow and
sediment-transport modeling, in Tools
in Fluvial Geomorphology, edited by G.M. Kondolf and H. Piegay,
pp. 539-576, John Wiley & Sons, Chichester.
Wiberg, P.L. and J.D. Smith, 1991, Velocity distribution and bed
roughness in high-gradient streams, Water Resour. Res., 5, 825-838.
Wilcock, P.R., 1996, Estimating local bed shear stress from velocity
observations, Water Resour. Res., v. 32, p. 3361-3366.
2. Initiation of Motion and Sediment Transport
Required Reading:
Andrews, E.D., 1983. Entrainment of
gravel from naturally sorted riverbed material, Geol. Soc. Amer. Bull.,
v. 94, p. 1225-1231.
Pitlick, J. and M.M. Van Steeter, 1998, Geomorphology and endangered
fish habitats of the upper Colorado River 2. Linking sediment
transport to habitat maintenance, Water Resour.
Res., v. 34, p. 303-316.
Wilcock, P.R. and B.W. McArdell, 1993, Surface-based fractional
transport rates: Mobilization thresholds and partial transport of a
sand and gravel sediment, Water Resour. Res., v. 29,
p.1297-1312.
Additional Papers:
Ferguson, R.I., and Wathen, S.J., 1998,
Tracer pebble movement along a concave river profile: Virtual velocity
in relation to grain size and shear stress, Water
Resour. Res., v. 34, p. 2031-2038.
Wiberg, P.L. and Smith, J.D., 1987. Calculations of the critical shear
stress for motion of uniform and heterogeneous sediments, Water
Resour. Res., v. 23, p. 1471-1480.
Parker, G., Klingeman, P.C. and Mclean, D.G., 1982. Bed load and size
distribution in paved gravel-bed streams, J. Hydraul. Div.
ASCE, v.108
(HY4), p. 544-571.
3. Hydraulic Geometry
Required Reading:
Pitlick, J. and R. Cress, 2002,
Longitudinal trends in the channel characteristics of a large
gravel-bed river, Water Resour. Res., v. 38(10), 1216,
doi:10.1029/2001WR000898
Pizzuto, J.E., 1992, The morphology of graded gravel rivers- a network
perspective, Geomorphology, v. 5, p. 457-475
Wolman, M.G. and Miller, J.P., 1960. Magnitude and frequency of forces
in geomorphic processes, J. Geol., v. 68, p. 54-74.
Additional Papers:
Ferguson, R., 1986, Hydraulics and
hydraulic geometry, Prog. Phys. Geog., v.10, p.1-31.
Parker, G., 1979. Hydraulic geometry of active gravel rivers, J.
Hydraul. Engr. ASCE, v. 105 (HY 9), p. 1185-1201.
Pizzuto, J.E., 1994, Channel adjustments to changing discharges, Powder
River, Montana, Geol. Soc. Amer. Bull., v. 106, p.
1494-1501.
Wolman, M.G. and Gerson, R., 1978, Relative scales of time and
effectiveness of climate in watershed geomorphology: Earth Surf.
Proc., v. 3, p. 189-208.
4. Meandering and Braided Rivers; Floodplains
Required Reading:
Everitt, B.L., 1968. Use of the
Cottonwood in an investigation of the recent history of a floodplain,
Am. J. Sci., v. 266, p. 417-439.
Lewin, J., 1976. Initiation of bed forms and meanders in coarse-grained
sediment, Bull. Geol. Soc. Amer., v. 87, p. 281-285.
Murray, A.B. and C. Paola, 1994, A cellular model of braided rivers,
Nature, v. 371, p. 54-57.
Additional Papers:
Church, M., Channel morphology and
typology, in The Rivers Handbook: Hydrological and Ecological
Principles, edited by P. Calow and G. Petts,
126-143, Blackwell, Oxford, 1992.
Dietrich, W.E. and Smith, J.D., 1983. Influence of the point bar on
flow through curved channels, Water Resour. Res., v. 19, p.
1173-1192
Hickin, E.J., 1974. The development of meanders in natural river
channels, Am. J. Sci., v. 274, p. 414-442.
Nelson, J.M., 1990, The initial instability and finite-amplitude
stability of alternate bars in straight channels, Earth-Sci. Rev., v.
29, p. 97-115.
Crowley, K.D., 1983. Large-scale bed configurations (macroforms),
Platte River Basin, Colorado and Nebraska: Primary structures and
formative processes, Bull. Geol. Soc. Amer., v. 94,
p. 117-133.
Wolman, M.G. and Leopold, L.B., 1957. River flood plains: some
observations on their formation, U.S. Geol. Surv. Prof. Paper 282-C, p.
89-109.
5. Longitudinal profile, downstream fining, & base level
Required Reading:
Bradley, W.C., Fahnestock, R.K., and
Rowekamp, E.T., 1972. Coarse sediment transport by flood flows on the
Knik River, Alaska, Bull. Geol.
Soc. Amer., v. 83, p. 1261-84.
Ferguson, R.I. et al., 1996, Field evidence for rapid downstream fining
of river gravels through selective transport, Geol., v. 24, p.
179-182.
Gasparini, N.M., G.E. Tucker, and R.L. Bras, 2004, Network-scale
dynamics of grain size sorting: Implications for downstream fining,
stream profile concavity, and drainage basin morphology, Earth Surf.
Process. Landforms, v. 29, p. 401-421.
Additional Papers:
Bradley, W.C., 1970. Effect of
weathering on abrasion of granitic gravel, Colorado River (Texas),
Bull. Geol. Soc. Amer., v. 81, p.
61-80.
Hack, J.T., 1957. Studies of longitudinal stream profiles in Virginia
and Maryland, U.S. Geol. Surv. Prof. Paper 294-B, 94 pp.
Schumm, S.A., 1993. River response to baselevel change: implications
for sequence stratigraphy, J. Geol., v. 101, p. 279-294.
6. Drainage basins, sediment yield, and landscape evolution
Required Reading:
Molnar, P. and England, P., 1990, Late
Cenozoic uplift of mountain ranges and global climate change- chicken
or egg, Nature, v. 346, p. 29-34.
Milliman, J.D. and Syvitski, J.P.M., 1992, Geomorphic/tectonic control
of sediment discharge to the ocean: The importance of small
mountain rivers,, J. Geol., v.
100, p. 525-544.
Tucker, G.E., 2004, Drainage basin sensitivity to tectonic and climatic
forcing: Implications of a stochastic model for the role of entrainment
and erosion thresholds, Earth Surf. Process. Landforms, v. 29, p.
185-205.
Additional Papers:
Howard, A.D., 1994, A
detachment-limited model of drainage basin evolution, Water Resour.
Res., v. 30, p. 2261-2285.
Pinet, P. and Souriau, M., 1987, Continental erosion and large-scale
relief, Tectonics, v. 7, p. 563-582.
Summerfield, M.A. and N.J. Hulton, 1994, Natural controls of fluvial
denudation rates in major world drainage basins, J. Geophys.
Res., v. 99, B7, p. 13,871-13,883.
