National Ecological Framework (15 of 23)

Surficial Geology

These data are presented as a set of components within each polygon.   The following attributes are included:

Name Description
UNIT Surficial Geology

The extent and nature of the surficial materials in this database are derived from the Surficial Materials Map of Canada (Fulton, 1996). The map identifies twenty-four types of materials.

UNIT Description
I Glaciers: Ice and minor morainal debris.
A Alluvial Deposits: stratified silt, sand, clay, and gravel; floodplain, delta, and fan deposits; in places overlies and includes glaciofluvial deposits.
  Marine Deposits: sediments deposited in marine waters under nonglacial conditions and remaining at or below present lake level.
mM Marine Mud: Fluid silty clay and clayey silt: deposited as quiet water sediments.
sM Marine Sand: Sand and locally gravel; deposited as sheet sands, lags, and beaches.
  Lacustrine Deposits: sediments deposited in lakes under nonglacial conditions and remaining at or below present lake level.
mL Lacustrine Mud:Fluid silty clay and clayey silt: deposited as quiet water sediments.
sL Lacustrine Sand: Sand and locally gravel; deposited as sheet sands, lags, and beaches.
E Eolian Deposits: sand and minor silt: dunes, blowouts, and undulating plains: In most places overlies deltaic sediments, coarse lacustrine sediments, or glaciofluvial deposits.
O Organic deposits: peat, muck and minor inorganic sediments; large bog, fen, and swamp areas where organic fill masks underlying surficial materials; generally >2 m thick.
  Colluvial Deposits: colluvial and residual materials deposited as veneers and blankets of debris through downslope movement and in place disintegration of bedrock; includes areas of rock outcrop.
bC Colluvial Blocks: Blocks, and rubble with sand and silt; derived from crystalline bedrock, medium grade metamorphic substrate, and cemented sandstone.
rC Colluvial Rubble: Rubble and silt; derived from carbonate and consolidated fine classic sedimentary rock substrate.
fC Colluvial Fines: Silt, clay, and fine sand: derived from substrate weakly consolidated shale and siltstone substrate.
sC Colluvial Sand: Sand and gravel; derived from poorly lithified sandstone and conglomerate substrate.
  Glaciolacustrine and Lacustrine deposits: sediments deposited in a glacial lake during deglaciation and subsequent lake drainage.
fM Fine Grained: Fine grained silt and clay, locally containing stones: deposited as quiet water sediments.
cL Coarse Grained: sand, silt, and gravel: deposited as deltas, sheet sands and lag deposits.
  Glaciomarine and Marine Deposits: sediments deposited from meltwater and floating ice, in marine waters, during deglaciation and subsequent regression.
fM Fine Grained: Dominantly silt and clay, locally containing stones; deposited as a quiet water sediment.
cM Coarse Grained: Sand and gravel: deposited as sheet sands, deltas, and extensive flights of beaches.
Mv Lag: Sand, gravel, and pockets of fine sediment; thin to discontinued sediment veneer and residual lag developed during marine submergence; includes areas of washed till and rock.
  Glaciofluvial Deposits: gravel and sand, deposited by meltwater streams.
Gp Plain: Sand and Gravel: deposited as outwash sheets, valley trains, and terrace deposits.
Gx Complex: Sand and gravel and locally diamicton: undifferentiated ice contact stratified drift, and outwash; locally includes till and rock.
  Glacial Deposits: silty, sandy, and clayey diamicton; formed by the direct action of glacier ice.
Tb Till Blanket: Thick and continuous till.
Tv Till Veneer: Thin and discontinuous till: may include areas of rock outcrop.
V Quarternary Volcanics: consolidated lava, breccia and tephra: dominantly basaltic and andesitic in composition; includes flows, volcanic piles and cinder cones.
  Rock: areas of abundant ( > 75%) rock outcrop.
Ra Alpine Complexes: rock, colluvium, and till: rock and Quarternary deposits complex in an area, characterized by alpine and glacial landforms.
R Undivided: rock with minor Quaternary deposits.

This database does not capture the linear features identified on the "Surficial Materials of Canada". The original source map identifies the former Wisconsin and maximum glaciation ice-limits; general ice flow direction based on drumlins, fluting, etc.; areas of hummocky topography; end and interlobate moraines; and eskers. All are important characterizing features that contribute to the delineation of the ecological units in the national framework.

A table on the back of the "Surficial Materialsof Canada" map lists the sources of surficial materials maps in Canada through 1993.


Fulton, R. J. (Compiler), 1996. Surficial Materials of Canada, Geological Survey of Canada, Natural Resources Canada. Ottawa. Map 1880A, Scale 1:5 000 000

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