Ice-sheet glaciation of the Puget lowland, Washington, during the Vashon Stade (Late Pleistocene)

Auteur :
THORSON, R. M.

Description :
Reconstructed longitudinal profiles for the Puget lobe at its maximum extent, suggest that the ice sheet may have been in a nearequilibrium state at the glacial maximum. Progressive northward retreat from the terminal zone was accompanied by the development of ice-marginal streams and proglacial lakes that drained southward during initial retreat, but northward during late Vashon time. Relatively rapid retreat of the Juan de Fuca lobe may have contributed to partial stagnation of the northwestern part of the Puget lobe. Final destruction of the Puget lobe occurred when the ice retreated north of Admiralty Inlet. The sea entered the Puget lowland at this time, allowing the deposition of glacial-marine sediments which now occur as high as 50 m altitude. These deposits suggest that a significant amount of postglacial isostatic and (or) tectonic deformation has occurred in the Puget lowland since deglaciation.


Type de document :
Article de périodique

Source :
Quaternary research New York, 1980, vol. 13, n°. 3, p. 303-321, Références bibliographiques : 42réf.

Date :
1980