During the middle and late Paleozoic, about a third of the Rodinian mass was torn apart and moved to equatorial regions. Most of these blocks were assembled by a series of plate collisions into the super continents of Laurussia [the Old Red continent] by the Devonian and Laurasia by the Pennsylvanian. Meanwhile the remains of Rodinia, Gondwana, rotated clockwise and moved northward to collide with Laurasia -- the result was the super continent Pangaea [all land]. Pangaea was shaped like a huge "pack man", mouth agape and facing eastward across the equator. The large,open mouth was the Tethys Ocean.
The Caledonian-Acadian orogeny marks the assemblage of the macro continent Laurussia, sometimes called the "Old Red continent". Meanwhile, Gondwana closes in from the south. An arc approaches western North America from the west.
Tectonics, Sedimentation, Paleogeography of North Atlantic Region
1st Order Global Tectonic Features
Link to other time periods