Insular Belt

{{Short description|Physiogeological region of North America}} [[Image:Geology belts of western Canada.png|thumb|right|250px|Geology belts of western Canada and southeast Alaska, including the Insular Belt (red)]] The '''Insular Belt''' is a [[physical geography|physiogeological]] region on the north western North American coast. It consists of three major island groups and many smaller islands and stretches from southern [[British Columbia]] into [[Alaska]] and the [[Yukon]]. It represents the [[Late Cretaceous]] to [[Eocene]] [[Accretion (geology)|accretion]] of what is known as the '''Insular Superterrane''' (formed from repeated accretion of multiple [[terrane]]s) to the [[North America]]n [[continent]].

The rocks that form the Insular Superterrane are [[Allochthon|allochthonous]], meaning they are not related to the rest of the North American continent. They consist of a series of [[volcanic rock|volcanics]], [[intrusion]]s and [[sedimentary rock]]s from the collision of an ancient [[volcanic arc|island arc]] called the [[Insular Islands]].<ref name="SI">[http://www.washington.edu/burkemuseum/geo_history_wa/Coast%20Range%20Episode.htm The Coast Range Episode (115 to 57 million years ago)]</ref> The exact collision of the Insular Islands remains uncertain.<ref name="SI"/>

The major island groups that compose the Insular Superterrane are, from south to north, [[Vancouver Island]] and the [[Gulf Islands]], the [[Haida Gwaii]] and the [[Alexander Archipelago]] in Alaska.

The region is noteworthy as it has the greatest physiographic relief from the depths of [[Queen Charlotte Sound (Canada)|Queen Charlotte Sound]] (which had been a coastal plain during the last ice age) to the heights of the [[Wrangell Mountains|Wrangell]] - [[Saint Elias Mountains]]. In general the region is extremely rugged with very little flat land except in certain regions (e.g. the east coast of Vancouver Island).

The region is thickly forested, having a temperate year round climate, with many of the world's largest trees.

==See also== *[[Geology of British Columbia]] *[[Intermontane Belt]] *[[Okanagan Highland]] *[[Omineca Mountains]] *[[Quesnel Highland]]

==References== {{reflist}}

==External links== *[http://www.bcadventure.com/adventure/frontier/physio/geology.htm Physiography of British Columbia] {{coord missing|British Columbia}}

[[Category:Geologic formations of Alaska]] [[Category:Physiographic sections]] [[Category:Volcanism of Alaska]] [[Category:Volcanism of British Columbia]] [[Category:Coast of British Columbia]] [[Category:Belt regions of the United States]]