MAP UNIT LETTER NOTATION

A terrain map unit symbol is composed of combination of letters which designate different characteristic of the terrain. The relative position of letters within the symbol indicates the characteristic that they represent.

Simple Terrain Symbol

TEXTURE (one to three lower case letters) describes the size, roundness and sorting of particles in mineral sediments and the fiber content of organic materials.

QUALIFIERS (up to two superscript upper case letters) are used where appropriate to provide information about surficial materials and geomorphological processes.

SURFICIAL MATERIAL (one upper case letter) is classified according to its mode of deposition.

SURFACE EXPRESSION (one to three lower case letters) describes the form (shape) of the land surface or the thickness of the surficial material.

GEOMORPHOLOGICAL PROCESSES(one to three
upper case letters) describes geomorphological processes
that are modifying either surficial material or land forms.

This map unit consists of a gravelly glaciofluvial terrace that overlies sandy lacustrine
material and is modified by gullies that are no longer active

Explanatory Notes

1. Units consisting of two or more types of terrain are designated by two or more groups of letters separated by slashes and/or dotes (see Composite Unites below)
2. Materials underlying the surface unit are shown by a symbol that is written beneath the surface symbol and separated from it by a horizontal line.

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TEXTURE

Texture refers to the size, roundness and sorting of particles in clastic sediments, and the proportion and degree of decomposition of the plant fibre in unconsolidated organic sediments.
Clastic Terms
Organic Terms

Explanatory Notes

1. The absence of a textural term from a unit symbol indicates that texture of the material was not observed in the field and cannot be reliably interpreted from air photos or from knowledge of the bedrock geology. The radar is referred to surficial material descriptions for general textural information.
2. Where two or three textural terms are used together, they are written in reverse order of importance and indicate that either the various textures are intermixed or interstratified

QUALIFIERS

Qualifiers qualify either surficial material or geological process terms. They are used to supply additional information about the mode of information and/or depositional environment of surficial material and the status activity of geological processes.

Symbol - Name Description

G - glacial

Used to qualify non-glacial surficial material where there is evidence that glacier ice affected the mode of deposition of materials (See surficial materials F^G, L^G, W^G).

A,I - active,inactive

Used to qualify surficial materials and geological processes with regards to their current state of activity.

Active:

there is evidence that a geological process is either operating continuously or is of a recurrent nature at the present time; there is evidence that the process of information of a surficial material is operative at the present time. Inactive: there is no evidence to suggest that a geological process is continuing or recurrent; the process of information of a surficial material has ceased.

Explanatory Notes

An activity qualifier for surficial material and geological processes are shown only in unit symbols where the current state of activity is contrary to the designated state.

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EXAMPLE TERRAIN MAP AND LEGEND

MAP UNIT LETTER NOTATION

Simple Terrain Symbol

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