The Lancaster Aulacogen is a geological structure underlying Lancaster Sound and

Prince Regent Inlet Prince Regent Inlet () is a body of water in Nunavut, Canada between the west end of Baffin Island ( Brodeur Peninsula) and Somerset Island on the west. It opens north into Lancaster Sound and to the south merges into the Gulf of Boothia. The A ...

in the

Arctic Archipelago The Arctic Archipelago, also known as the Canadian Arctic Archipelago, is an archipelago lying to the north of the Canadian continental mainland, excluding Greenland (an autonomous territory of the Danish Realm, which is, by itself, much larger ...

Nunavut Nunavut is the largest and northernmost Provinces and territories of Canada#Territories, territory of Canada. It was separated officially from the Northwest Territories on April 1, 1999, via the ''Nunavut Act'' and the Nunavut Land Claims Agr ...

, Canada. It formed as a result of

extensional tectonics Extensional tectonics is concerned with the structures formed by, and the Tectonics, tectonic processes associated with, the stretching of a planetary body's Crust (geology), crust or lithosphere. Deformation styles The types of structure and the ...

during the Eurekan Rifting Episode, which took place in the Canadian Arctic Rift System from the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...

to the

Tertiary Tertiary (from Latin, meaning 'third' or 'of the third degree/order..') may refer to: * Tertiary period, an obsolete geologic period spanning from 66 to 2.6 million years ago * Tertiary (chemistry), a term describing bonding patterns in organic ch ...

References

Aulacogens Geology of Nunavut {{Canada-geology-stub