Geomorphology, Sedimentary Structures, and Genesis of Dome Dunes in Western Canada

Abstract

<jats:title>ABSTRACT</jats:title><jats:p>Dome dunes in four stabilized, inland dune fields in western Canada are predominantly composed of horizontal to low-angle cross-strata, indicating that slip face development was rare. Dip angles of lee side deposits decrease upward in the dome dunes. The spread of dip directions increases with elevation in the dunes, spanning 360° for topset deposits. Sedimentary structures indicative of moisture (adhesion laminae) and vegetation (scour surfaces) occur in the dunes and denivation features are also present. Sediment adhesion is responsible for the maintenance of the dome morphology. Sediment sorting within the dome dunes is poorer than in other local dune types in the vicinity, suggesting that less reworking/ineffective selective transport occurred and that the dome dunes are more efficient in retaining sediment. The rarity of slip face and grainfall deposits and the abundance of low angle deposits indicate that preferential accumulation of sediment at the top of the lee side did not occur. Development of domal morphology is a consequence of the inhibition of slip face development. In inland, relatively moist boreal environments, the primary factor limiting or precluding sediment accumulation at the crest of the dunes is a low rate of sedimentation.</jats:p>

Coversand and Pleistocene palaeosols in the Landes region, southwestern France

“…The first 15 cm show lamination due to alternating sand and silty sand approximately parallel to the palaeosol surface and slightly deformed by cryoturbation. Similar facies have been described in boreal and Arctic regions (Good and Bryant, 1985;Lea, 1990;Halsey and Catto, 1994) and in the northern European coversand (Schwan, 1986;Kasse, 1997). They are attributed to aeolian transport on wet soils, which trap the fine-grained particles and prevent dune formation.…”

Sedimentology and preservation of aeolian sediments on steep terrains: Incipient sand ramps on the Atacama coast (northern Chile)

“…This is testified by the occasional occurrence of granule and pebble lags along such surfaces. Similar aeolian facies have been identified in sand-sheet deposits (Fryberger et al, 1979;Kocurek, 1986;Lea, 1990;Halsey and Catto, 1994;Williams, 1998) and in aeolian accumulations of periglacial settings (Hètu, 1995;Hètu and Gray, 2000).…”

Inland aeolian deposits of south‐west France: facies, stratigraphy and chronology

“…Parabolic dunes typify vegetated landscapes with reduced sand transport (McKee, 1979) and initiate from local blowouts. A 3‐m‐high dome‐like dune without distinct lee face has been cut by trenches at Retjons, and is thought to represent a downwind, poorly developed end‐member of the parabolic dune generation (Halsey and Catto, 1994).…”