Alexander Terrane
The Alexander Terrane 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.
Rocks assigned to this terrane underlie much of Southeast Alaska, the north coast of British Columbia, and the Yukon southwest.
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.
This terrane also forms part of the composite Wrangellia Terrane.
Origin
The original location of the Alexander Terrane remains uncertain. Some evidence, including detrital zircon geochronology, suggests it may have formed along the margins of ancient Baltica or Laurentia,however, paleomagnetic, isotopic, and fossil data indicate a possible origin near the margins of ancient Siberia or Arctic continents.