Saguenay Graben

[1] During the opening of one of these oceans, fragmentation of the landmass occurred creating two fault planes, one to the north and one to the south.

The resulting bedrock between dropped down along the normal faults, creating the Saguenay Graben.

[3] The glaciers cut into the graben and widened it in some places as well as making it considerably deeper in others.

The Saguenay Graben is characterized primarily by the rock types: gneiss, anorthosite and granite that are Proterozoic in age.

There are two outliers of limestone and shale of the Paleozoic that are found only in the graben due to its faulting.