Soil_Erosion50k_dki

Metadata

Created new base file of terrain stability mapping done in FRBC days downloaded from Energy and Mines Mapplace.  Most of these projects are late 1970’s style terrain classification.  Merged base files fr67, fr65, fr71, fr64, fr59 to create soil_base_merge4.  Ran union with 50k slope mapping (tslp_dki_srm) to create resultant file soil_erosion_50k.  Rational for this process is previous file sferopot_dki did not include fr59 mapping, and similarily was unclear who completed the proxy mapping for soil erosion.  Whatever process was used was not documented or easily identified, and comparison with recent work, just didn’t make sense.

Process for assigning soil erosion potential as follows based on Madrone Consultants Ltd. Process documented in one of their mapping projects:

VERY LOW: irrespective of surface material and texture, slope code equal to 1,

LOW: irrespective of surface material and texture, slope code equal to 2 or 3,

MODERATE: for all ‘%fluvial’ surface material on slope codes less than 4 (i.e. 1, 2, 3).  This was calculated for colluvium or morainal surface material for slope codes 4, 5 or 6 where there wasn’t a geologic process identified such as gully or avalanche..

HIGH: for all ‘%fluvial’ surface material on slope codes equalling 4, 5 or 6.  For colluvium and morainal surface material, slope codes equalling 4, 5, 6 where a texture was specified as either ‘s’ (sand) or ‘gs’ (gravel-sand), and all slope codes of 7.
If gullying was present without existing potential rating from above, a HIGH rating was given for slopes equalling 4, 5 or 6 regardless of surface material.  The same was generated for avalanche areas.

VERY HIGH: for all ‘%fluvial’ surface material on slope codes greater than 7.  This rating was given to morainal and colluviam surface textures on slope codes greater than 8.
If gullying was present without existing potential rating from above, a VERY HIGH rating was given for slopes greater than 7, regardless of surface material.  The same was generated for avalanche areas.

Created: December 29, 2008
Created by: BElls