Page 46 - Fundamentals of Geomorphology

WHAT IS GEOMORPHOLOGY? 29

accepted even before Lyell’s death, and non-actualism with dating techniques. Geomorphology has engaged
and, in particular, catastrophism are discussed in geo- in methodological debates over the extent to which the
morphological circles. present is a key to the past and the rates of Earth surface
processes.
SUMMARY
ESSAY QUESTIONS
Geomorphology is the study of landforms. Three
key elements of geomorphology are land form, geo- 1 To what extent do process
morphic process, and land-surface history. The three geomorphology and
main brands of geomorphology are process (or func- historical geomorphology
tional) geomorphology, applied geomorphology, and inform each other?
historical geomorphology. Other brands include tec-
tonic geomorphology, submarine geomorphology, plane- 2 Discuss the pros and cons of a
‘systems approach’ in
tary geomorphology, and climatic geomorphology. Form geomorphology.
is described by morphological maps or, more recently, by
geomorphometry. Geomorphometry today uses digital 3 Explain the different types of
elevation models and is a sophisticated discipline. Armed equilibrium and non-equilibrium
with a powerful combination of predictive models, field recognized in geomorphic systems.
observations, and laboratory experiments, process geo-
morphologists study geomorphic processes in depth.
They commonly use a systems approach to their subject.
Form systems, flow or cascading systems, and process– FURTHER READING
form or process–response systems are all recognized.
Negative feedback and positive feedback relationships Ahnert, F. (1998) Introduction to Geomorphology.
are significant features in the dynamics of geomorphic London: Arnold.
systems. The great achievements of process geomor- A good starting text with many unusual examples.
phology include notions of stability, instability, and Bloom, A. L. (1998) Geomorphology: A Systematic Anal-
thresholds in landscapes, the last two of which belie ysis of Late Cenozoic Landforms, 3rd edn. Upper Saddle
simplistic ideas on cause and effect in landscape evo- River, N. J., and London: Prentice Hall.
lution. Uncertainty surrounds the issue of geomorphic
process rates. Magnitude and frequency impinge on A sound text with a focus on North America.
part of this uncertainty. At first it was believed that Goudie, A. S. (ed.) (1994) Geomorphological Techniques,
medium-magnitude and medium-frequency events did 2nd edn. London and New York: Routledge.
the greatest geomorphic work. Some studies now sug- Covers the topics not covered by the present book – how
gest that rare events such as immense floods may have geomorphologists measure form and process.
long-lasting effects on landforms. Land-surface history Kennedy, B. A. (2005) Inventing the Earth: Ideas on
is the domain of the historical geomorphologist. Some
early historical work was criticized for reading too much Landscape Development Since 1740. Oxford: Blackwell.
A good read on the relatively recent history of ideas about
into purely morphological evidence. Nonetheless, his- landscape development.
torical geomorphologists had some great successes by
combining careful field observation with the analysis Ritter, D. F., Kochel, R. C., and Miller, J. R. (1995) Pro-
of the sedimentary record. Historical geomorphologists cess Geomorphology, 3rd edn. Dubuque, Ill., and London:
reconstruct past changes in landscapes using the meth- William C. Brown.
ods of environmental and stratigraphic reconstruction A good, well-illustrated, basic text with a fondness for
or topographic chronosequences, often hand in hand North American examples.