Jim Baichtal(FS) is going to speak at the school to the students and community.
The Alexander Archipelago, Southeastern Alaska. For years it was
thought that glaciers covered much of the coastline of British
Columbia and Southeastern Alaska to the edge of the continental
margin extending as a large uniform front. Nothing lived along the
coast until the ice retreated, then plants and animals soon followed.
Exploration of the caves in Southeast Alaska yielded bones of
mammals, birds, and fish dating to beyond the limits of radiocarbon
methods. Animals have been on the landscape for over 50,000 years,
refuting previous models of glaciation.
Our new model for glaciation in involves the dynamic processes
associated with the effects of glacial ice on the land and sea levels.
As the glaciers advanced during the last ice age, the weight of the ice
depressed the earth’s surface beneath it. As the glaciers grew the
global sea levels fell. As the glaciers melted, sea level rose, and the
lands depressed by the weight of the ice rapidly rebounded.
The first plants and animals in Southeast Alaska were living on this
rapidly changing landscape, first on the now flooded coastal plane,
then on shorelines now well beyond the reach of the sea. Dr. Jim
Baichtal, Forest Geologist with the Tongass National Forest, will
explain how shell deposits now stranded hundreds of meters above
sea level helped change the “Wall of Ice” paradigm and define the
complexity of Alaska’s glacial history.