Application to Surficial Materials
Application To Geomorphological Processes
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Qualifier symbols provide additional information about the mode of formation and/or the depositional environment of surficial materials and the status of activity of geomorphological processes.

APPLICATION TO SURFICIAL MATERIALS

Qualifiers are used to provide additional information about surficial materials. These are denoted by an upper case superscript that follows the surficial material symbol. Two distinct types of qualifiers are available: (1) glacial qualifiers, and (2) activity qualifiers.

Glacial Qualifiers

The "glacial" descriptor "G" is used to qualify surficial materials where there is direct evidence that glacier ice exerted a strong although secondary control upon the mode of origin of the material. The use of this qualifier implies that glacier ice was close to the site of deposition of the material. The most common types of glacially-modified materials are included in the surficial material classes. However, the "glacial" modifier may be used with other materials where necessary, in which case appropriate descriptions should be added to the map legend and terrain report.

Application and Examples:

• Applied to surficial materials that exhibit any of the following: kettled or irregular (hummocky or ridged) surfaces that result from the melting of buried or partially buried ice; slump structures indicating partial collapse of a landform due to melting of supporting ice; ice-contact and moulded forms such as crevasse fillings and eskers; non-sorted and non-bedded gravel with a wide range of particle sizes resulting from very rapid aggradation at an ice front; the presence of flowtills; and the presence of ice-rafted stones in glaciolacustrine or glaciomarine deposits.

Examples:	kettled outwash plain	sgFGp-H
	silty lacustrine terrace with ice-rafted stones	zLGt

• Surficial materials that display none of the ice-contact features described above can be qualified by the "glacial" term if reconstruction of geomorphological history indicates a glacial source.

Application and Examples:

• By definition, each surficial material has an assumed status of activity. If the actual state of activity of the surficial material is contrary to the assumed state, then the actual state is indicated by attaching the appropriate superscript to the surficial material symbol. If the actual state is the same as the assumed state, no superscript is used.

Examples:	fluvial terrace high above river level (actual state and assumed state, are the same)	Ft (qualifier is not shown)
	floodplain subject to shifting channels (actual state is active contrary to assumed state)	FAp (qualifier is shown)
	outwash in front of a modern glacier (actual state is active, contrary to assumed state)	sgFAGp (qualifier is shown)

• A surficial material is "active" if there is evidence of its recent deposition. The nature of the evidence varies with the type of depositional process, but will include some of the following:

i)	Absence of vegetation or presence of immature or successional vegetation; recently disturbed or damaged vegetation.
ii)	Lack of soil development (immature soil); recently deposited sediment overlying soil or litter layers (cumulic soil horizons).
iii)	Fresh, unweathered surface with no lichen or moss cover.
iv)	Historical records and air photographs; eyewitness accounts.
v)	Indications of an active sediment supply.

APPLICATION TO GEOMORPHOLOGICAL PROCESSES

Application and Examples:

• By definition all geomorphological processes are assumed to be active except for deglacial processes which are assumed to be inactive (see Geomorphological Processes). If the actual state of activity of the geomorphological process is contrary to the assumed state, then the actual state is indicated by attaching the appropriate superscript to the geomorphological process symbol. If the actual state is the same as the assumed state, no superscript is attached.

Examples:	active sand dunes and deflation hollows (actual and assumed states, are the same)	sEAr-D (process qualifier is not shown)
	vegetated sand dunes and deflation hollows (actual state is inactive, contrary to assumed state)	sEr-DI (process qualifier is shown)

• Geomorphological processes should be considered active for terrain mapping purposes if there is evidence of current or recent occurrence, or likely future occurrence. Indicators of present or future activity include freshly deposited sediments, visible slope instability, soil and vegetation characteristics or other features in the landscape (refer to Activity Qualifiers for surficial materials).
  
  
• The use of the "activity" qualifiers is not defined in quantitative terms (e.g., once every hundred years) because the assessment of the frequency of most geomorphological processes (e.g., floods, snow avalanches) is beyond the scope of this terrain classification system.

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