The Meguma terrane is a terrane exposed in southern Nova Scotia, that became joined to the present North American landmass as part of the Appalachian orogeny. Composed largely of Cambrian to Ordovician sedimentary deposits, it is joined to the Avalon terrane along the Minas Fault Zone, which runs east-west from Chedabucto Bay to Cobequid Bay and the Minas Basin. Numerous Devonian and Carboniferous plutons are also found. The extent of the formation is unclear; some geologists believe that a magnetic anomaly along the coast of Cape Cod may represent a suture between the Meguma and Avalon terranes in that region. Unlike the Avalon terrane, the Meguma terrane has not been definitively associated with territory on the other side of the Atlantic. It may be represented in the Galicia-Tras-Os-Montes Zone in Spain and Portugal. It appears to have been separated from Gondwana, but there are competing theories as to whether it came from the northern or southern coast.
Geologically this area is of interest not only to students of geological history, but because metamorphism produced gold deposits which were mined extensively in the latter half of the 19th century, and which remain potentially exploitable today.