What is the crust type of the Wrangellia terrane?

flood basalt
The defining feature of the Wrangellia terrane remains its layer of ancient flood basalt. This now forms the Nikolai Greenstone, and is found on both the south and north side of the Wrangell Mountains, and presumably underneath the mountains as well. It is also seen on the south flank of the eastern Alaska Range.

Where did Wrangellia form?

The Wrangellia flood basalts in Alaska are remnants of an oceanic plateau that erupted in the eastern Panthalassic Ocean over <5 Ma in the Middle to Late Triassic, with accretion to western North America occurring in the Late Jurassic or Early Cretaceous [Jones et al., 1977].

Is Vancouver Island a terrane?

Geology of British Columbia and Vancouver Island. Most of Vancouver Island is made up of the Wrangellia Terrane (part of the Insular Super Terrane) shown here in shades of green. The Wrangellia Terrane arrived on the west coast of North America some time around 100 m.y. ago. The Nanaimo Gp.

When was Wrangellia accreted?

Wrangellia flood basalts formed as an oceanic variety of a large igneous province (LIP) in the Middle to Late Triassic, with accretion to western North America occurring in the Late Jurassic or Early Cretaceous (e.g. Richards et al., 1991).

Where did the rocks of Wrangellia come from?

Rocks of Wrangellia (the individual terrane, not the composite terrane) were originally created in the Pennsylvanian to the Jurassic somewhere, but probably near the equator, in the Panthalassic Ocean off the west coast of the North American craton as island arcs, oceanic plateaus, and rock assemblages of the associated tectonic settings.

How did Wrangellia come to be in Alaska?

Every Alaskan lives on borrowed crust! America was build by migrants, but in Alaska the land itself formed that way. And finally, it was time for Wrangellia to arrive. This was already a complex entity: Wrangellia consists of a variety of different terranes which had merged before arrival at Alaska.

Where does the Wrangellia Terrane start and end?

A terrane extending from south-central Alaska through southwestern Yukon and along the Coast of British Columbia. The Wrangellia Terrane (named for the Wrangell Mountains, Alaska) is a terrane extending from the south-central part of Alaska through southwestern Yukon and along the Coast of British Columbia in Canada.

When did the eruption of Wrangellia take place?

The eruption of Wrangellia flood basalts broadly coincides with major biotic and environmental changes worldwide that occurred at the end of Carnian time (Furin et al., 2006).