CGRG Bibliography of Canadian Geomorphology
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Author : Axeslon, J.; and Walker, I.J.
Date : 2003.
Title : Historical and recent morphodynamics of coastal dunes on Graham Island, Haida Gwaii (Queen Charlotte Islands), British Columbia.
Publication : 'On the Edge' Conference. Joint Meeting of the ACMLA, CAG, CCA and CRSA. May 27 to May 31, 2003. University of Victoria, Victoria, British Columbia.
Issue :
Page(s) :
Abstract
Active parabolic dune systems, comprised of unconsolidated Quaternary sediments, are part of the dynamic beaches and steep coastal bluffs that make up the east coast of Graham Island, Haida Gwaii (Queen Charlotte Islands). The northeast shores of Graham Island, Naikoon Park, are characterized by strongly seasonal wind patterns with frequent southeasterly gales predominating in winter. The purpose of this paper is to characterize the morphodynamic nature of coastal dunes in this region. Through the use of historical air photos, local wind data and field observation it is evident that parabolic dunes are highly active in this moist marine climate. The average dune alignment over a thirty-one year period of air photo coverage is 336°+7.65°. Transport potential was measured using the Fryberger method (1979) resulting in a high resultant drift potential of 1925 vector units, and a resultant drift direction of 345?. Dune activity and migration is apparent by the presence of covered and uncovered sitka spruce located on dune ridges and on established foredunes. Adventitious root structures have been uncovered through blowout development, and many trees are titled or have extensive bark damage as a result of burial. Dune orientation and sand rose results provide a strong case that despite wet winter months that dunes are highly active in this area as a result of intense southeast winter winds and storms.
Bibliography of Canadian Geomorphology