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geomorphology Powered By Docstoc
					Geomorphology (from Greek: γῆ, ge, "earth"; μορφή, morfé, "form"; and λόγος, logos, "study")

Geomorphology is the study of the form and structure of the Earth. Geomorphologists try to
understand why landscapes look the way they do: to understand landform history and
dynamics, and predict future changes through a combination of field observation, physical
experiment, and numerical modeling.

The size and shape of the Earth's surface, on land and beneath the sea, is constantly
changing. This is due to landform evolution and the processes of weathering, which have
altered the original geological shape of the rocks. Landform evolution and weathering are
controlled by many different processes, the most important being climate and Earth
movements, or plate tectonics.

Plate tectonics alter the geomorphology of the landscape more dramatically than any other
natural process. For instance, they may create the steep slopes associated with mountain
chains and volcanoes, whose continual uplift or outpouring of lava contributes more to
topography than climate. Continual fault movements in earthquake-prone areas will also tend
to dominate the landscape more than the modifying effects of erosion.

Landscapes experiencing different types of climate are subject to very different types of
weathering. In cold, mountain areas, glaciation is the dominant shaping force at work; water is
the main weathering agent in warm, humid coastal and river regions; and wind erosion is
responsible for shaping many of the landforms in dry deserts.

Landforms evolve in response to a combination of natural and anthropogenic processes. The
landscape is built up through tectonic uplift and volcanism. Denudation occurs by erosion and
mass wasting, which produces sediment that is transported and deposited elsewhere within
the landscape or off the coast. Landscapes are also lowered by subsidence, either due to
tectonics or physical changes in underlying sedimentary deposits. These processes are each
influenced differently by climate, ecology, and human activity.

Primary surface processes responsible for most topographic features include wind (Aeolian),
waves, chemical dissolution, mass wasting, groundwater movement, surface water flow
(fluvial), glacial action, tectonism, and volcanism. Other more exotic geomorphic processes
might include periglacial (freeze-thaw) processes, salt-mediated action, or extraterrestrial

Practical applications of geomorphology include measuring the effects of climate change,
hazard assessments including landslide prediction and mitigation, river control and restoration,
coastal protection, and assessing the presence of water on Mars.

In the earth sciences and geology sub-fields, a landform or physical feature comprises a
geomorphological unit, and is largely defined by its surface form and location in the landscape,
as part of the terrain, and as such, is typically an element of topography. Landform elements
also include seascape and oceanic waterbody interface features such as bays, peninsulas,
seas and so forth, including underwater terrain features such as submersed mountain ranges,
volcanoes, and the great ocean basins under the thin skin of water, for the whole earth is the
province and domain of geology.

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