Parks / Ontario
Lawrence Islands National Park
The densely wooded archipelago
is really the high points of a Precambrian mountain
range that once linked the southern edge of
the Canadian Shield and the Adirondack Mountains
of New York state, scraped smooth by the passage
of glaciers and nearly submerged by the St.
Lawrence River. This geological formation, called
the Frontenac Axis, a 40 kilometre-wide granite
bridge, during the last ice age was buried beneath
massive glaciers 3 kilometres thick. When the
glaciers receded 12 000 years ago, the mountains
were overspread by floodwaters draining into
the Atlantic Ocean along the St. Lawrence Valley.
Those ancient mountain peaks formed the fragmented
string of 20 islands and about 90 rocky shoals
and islets - stepping-stones between the landmasses.
The geology of the area is predominantly rocky
rugged shoreline interspersed with significant
wetlands and low vegetated inclines that support
a broad range of flora and fauna.