Geographic change in the glacial period

These maps show the extent of glacier ice in Atlantic Canada from the last glacial maximum until 12,000 radiocarbon years ago. Ice cover is indicated by a transparent white tone. The thin blue lines represents ice-flow lines. The heavy dashed lines are ice divides. Further information on the process of deglaciation is contained in recent paper: Shaw, J., Piper, D.J.W., Fader, G.B, King, E.L., Todd, B.J., Batterson, M.J., and Liverman, D.J.E., 2006. A conceptual model of the deglaciation of Atlantic Canada. Quaternary Science Reviews, 25, 2059-2081.

20 kaGlacier ice extended to the edge of the continental shelves in most areas. Major ice streams occur in the Bay of Fundy, the Laurentian Channel, and off northeast Newfoundland.

20 ka

Glacier ice extended to the edge of the continental shelves in most areas. Major ice streams occur in the Bay of Fundy, the Laurentian Channel, and off northeast Newfoundland.

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20 kaBy 20,000 radiocarbon years before present glacier ice has retreated in some areas, notably off northeast Newfoundland and in the Bay of Fundy.

20 ka

By 20,000 radiocarbon years before present glacier ice has retreated in some areas, notably off northeast Newfoundland and in the Bay of Fundy.

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18 kaThe ice margin continues to retreat in the Bay of Fundy, on the western Scotian Shelf, and off northeast Newfoundland.

18 ka

The ice margin continues to retreat in the Bay of Fundy, on the western Scotian Shelf, and off northeast Newfoundland.

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16 kaIce-margin retreat is occurring in deeper water, so that ice remains grounded in shallow areas such as the eastern Scotian Shelf.

16 ka

Ice-margin retreat is occurring in deeper water, so that ice remains grounded in shallow areas such as the eastern Scotian Shelf.

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14 kaJust before 14 ka BP, extensive retreat occurred in the Gulf of St. Lawrence. Retreat off Newfoundland has isolated an ice cap on the Grand Banks.

14 ka

Just before 14 ka BP, extensive retreat occurred in the Gulf of St. Lawrence. Retreat off Newfoundland has isolated an ice cap on the Grand Banks.

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13 kaBy now the retreating ice margin is near modern Quebec City. Much of the west coast of Newfoundland is also ice-free.

13 ka

By now the retreating ice margin is near modern Quebec City. Much of the west coast of Newfoundland is also ice-free.

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12 kaBy 12 ka BP ice is mostly on land, and islands are present offshore. The changing geography from 13 ka BP onwards is explored Progression of sea-level change.

12 ka

By 12 ka BP ice is mostly on land, and islands are present offshore. The changing geography from 13 ka BP onwards is explored Progression of sea-level change.

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