Terrain - A User's Guide - Terrain Map Symbols


	B.C. Home

MOE > ESD > Ecosystems Branch >Terrain > A User's Guide

Ecosystems Branch

	TERRAIN TOPICS
	Terrain Home
	Terrain Overview
	Types of Terrain Maps
	Access to Maps & Data
	Terrain Listserv
	Standards & Guidelines
	•	A User's Guide to Terrain Maps in BC
	•	Terrain Information
	•	Terrain Map Symbols
	•	Character of Surficial Materials
	•	Texture of Surficial Materials
	•	Surface Expression (Landforms)
	•	Geomorphological Processes
	•	Land Capability
	•	Assessment of Geomorphological Hazards
	•	Granular Resources
	Program Updates
	Site Map

RELATED SITES

Ecology

Soils

Wildlife


	Ministry of Environment



	Terrain

Terrain Map Symbols

Information is shown on terrain maps by the use of letters and on-site symbols. Each group of letters constitutes a "terrain symbol", for example "zL^Gt-V". The letters within the group are arranged so that each letter position represents a particular characteristic of the terrain. The arrangement of letters and groups of letters is explained below by means of examples. Definitions of all individual letter symbols used on each terrain map are given in the map legend. The most commonly used letter symbols are defined in this booklet. On-site symbols are used to provide additional information about surficial materials or landforms that cover areas that are too small to show as terrain units. On-site symbols used on each terrain map are defined in the map legend.

Terrain Map

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.

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

COMPOSITE TERRAIN UNIT SYMBOLS are used where two or three different kinds of terrain occur within a map unit. The symbol consists of two or three terrain unit symbols that are separated by slashes or dots:

. components on either side of this symbol are of approximately equal extent (1:1).
/ the component in front of the slash is more extensive than the one that follows (approximately 2:1).
// the component in front of the double slash is considerably more extensive than the one that follows (ranges from 3:1 to 9:1)

Examples:

rCv/Rs	a veneer (v) of rubbly (r) colluvium (C) is more extensive than steep (s) bedrock (R) slopes.
Mb.Cv/R	a blanket (b) of moraine (M) and colluvial veneer (Cv) of equal extent, and both are more extensive than bedrock (R).

Note: a geomorphological process affecting any part of a composite unit is always written at the right hand side of the composite terrain unit symbol; see example in illustration.

Terrain Map

STRATIGRAPHIC SYMBOLS are used where information is available about unconsolidated material that underlies the surface layer of material.

Examples:

	glaciofluvial (F^G) gravels (g) in the form of a terrace (t) that overlies undulating (u) till (M)
	a veneer (v) of eolian (E) sand (s) overlies a terrace of fluvial gravels (gFt) which in turn rest upon lacustrine (L) silt (z)
	a veneer of fluvial sand overlies a gravel flood- plain; the area is subject to periodic flooding (F^A)

ON-SITE SYMBOLS are used to show the specific location of some landforms and other features that cannot be accommodated by terrain unit symbols.

Examples:

	scarp (steep slope)
	drumlin (ice flow direction indicator)
	kettle (depression)
	cirque (head of glacial trough)
	glacial meltwater channel

Web Page Last Updated: February 6, 2007