The Silurian Period is the shortest of all the periods of the Paleozoic Era, lasting only 30 million years from 438 million years ago until 408 million years ago. As the Silurian Period opens, the eastern margin ofLaurentia was dominated by the Taconic Highlands that had been created during the Taconic Orogeny at the close of the Ordovician. The rest of the craton was essentially flat-lying and covered by a shallow sea. Except for the northeastern margin which was involved in a major orogeny following the Taconic Orogeny, Laurentia was tectonically quiet throughout the Silurian. About 10 million years before the collision of A valonia in the Devonian , Baltica collided with the northeastern portion of Laurentia during the Caledonian Orogeny and creating the Caledonian Mountains. The Caledonian Orogeny involved eastern Greenland, the northeastern margin of Laurentia down to about the latitude of Nova Scotia, western British Isles from Ireland and Scotland to the eastern margin of Scandinavia (Figure 1 ). The Appalachian region was not affected by the Caledonian Orogeny.
Renton, John J. and Repine, Thomas, "The Silurian Period" (2016). Readings and Notes. 14.