Alexander Terrane
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Alexander Terrane | |
|---|---|
physiographic section | |
| Location | Alaska; British Columbia; Yukon |
| Part of | Wrangellia Terrane |
| Dimensions | |
| • Length | 1,000 km (620 mi) |
| • Width | 250 km (160 mi) |
The Alexander Terrane (named for the Alexander Archipelago in Alaska) is a neoproterozoic continental fragment that originated far from its current location, before being transported and accreted to western North America in the Middle Jurassic.[1] This terrane also forms part of the composite Wrangellia Terrane.[2]
Rocks assigned to this terrane underlie much of Southeast Alaska, the north coast of British Columbia, and the Yukon southwest.[1] The Alexander Terrane is intruded by Late Jurassic and Early Cretaceous plutons and is overlain to the east by Upper Jurassic through mid-Cretaceous clastic strata and mafic volcanic rocks.[3]
In British Columbia, the terrane crops out primarily in the Coast Mountains, including the Kitimat Ranges, Chatham Sound, and Haida Gwaii, and continues to Klemtu.[1]
