By Early Devonian time, the seas had receded. There were two main landmasses at this time. The southern continent Gondwanaland consisted of South America, Africa, Madagascar, India, Australia and Antarctica. The northern continent Laurasia consisted of North America, Greenland, Europe and most of Asia. Movements of the earth's crust uplifted the land and brought the continental landmasses closer together. When Gondwanaland and Laurasia came in contact during the Middle Devonian, they fused together to produce one large supercontinent called Pangea.

Before this time, the Avalon and Meguma Zones of Nova Scotia were widely separated because they belonged to different continental landmasses (Laurasia and Gondwanaland, respectively). The formation of Pangea, however, joined them together for the first time to form the single geological entity we now know as Nova Scotia. From the Middle Devonian on, the province was in one piece and had a similar geological history continuing to the present day.

Geographically speaking, Nova Scotia was situated near the equator, wedged between the North American and African continental plates.

Rocks of Nova Scotia

The union of the ancient continental landmasses initiated an impressive mountain building episode called the Acadian Orogeny. The mountains produced by the Acadian Orogeny (the Appalachians) may have been similar in appearance to the present day Canadian Rocky Mountains.

The orogeny was nearing its completion in the Middle Devonian, with folding and metamorphism of most rocks in Nova Scotia. Large volumes of rock were melted and the resulting granitic magma was intruded into overlying rocks (about 370 million years ago), forming the South Mountain batholith and the many other smaller intrusions. The numerous metal deposits of southern Nova Scotia, including gold, are believed to have resulted from the intrusion of these granites. During this time, the gabbroic and dioritic rocks at Liscomb were intruded into the Meguma Group from deeper levels of the crust.

After the Appalachian Mountains were formed, there was a period of relaxation in which the Earth's crust attempted to regain its equilibrium. This readjustment caused the crust to break up along large faults into a series of " blocks". Some of these blocks sank downward, while others were forced up. The uplifted blocks were rapidly eroded, and the debris fell or was swept into the rift valleys created by the sunken blocks.

Paleoenvironment

Primitive land plants found as fossils in both the Torbrook and Murphy Brook formations of Nova Scotia suggest a uniformly warm and moist climate over a wide region in the Early Devonian. Shallow water environments were inhabited by various plants and animals. Fish were abundant, as were insects and other arthropods. Amphibians, the first animals to breathe air, were on the rise.

Starting in the Middle Devonian, the climate changed gradually from warm and moist to hot and arid.