The map on the left shows the widespread distribution of the Devonian age granitic plutons across northern New England. It does not show their extension into Quebec. Some of the plutons are of immense areal extent. On the right is a geological time scale with a focus on the Devonian period. Radiometric dating of granitic plutons in our region indicates emplacement relatively late in the Devonian period. The Stanstead Pluton itself has not been dated but its nearest neighbour, the Derby Pluton, has a radiometric age of between 370 and 372 Ma.
