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A terrane is a crustal block or fragment that preserves a distinctive geologic history that is different from the surrounding areas and that is usually bounded by faults.

Accreted terranes are those that become attached to a continent (e.g., western North America) as a result of tectonic processes.

Superterranes are defined as composite terranes grouping individual terranes and other assemblages sharing a distinctive tectonic history.

One example of accreted terranes is the Canadian Cordillera:

terraneThe Canadian Cordillera can be divided into five sub-parallel morphotectonic belts, the development of which reflects the history of Mesozoic and Cenozoic collision and deformation along the northwestern margin of North America. This process involved the accretion of allochthonous superterranes to the North American plate. The Intermontane superterrane was accreted approximately 180 Ma, while the Insular superterrane was accreted approximately 100 Ma.
The Coast Belt is considered to contain the suture resulting from the mid-Cretaceous collision between the exotic Insular superterrane and the previously accreted Intermontane superterrane. This suture has since been overprinted by an evolving subduction-related magmatic arc that persists today as one part of the modern Cascadia subduction zone. The Omineca belt represents the suture to the east of the Intermontane superterrane.

see: Coney et al., 1980; Monger et al., 1982, 1985; Gabrielese and Yorath, 1991; Monger and Price, 1979.

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