The Carmacks Group is a

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', ...

volcanic group A volcanic group is a stratigraphic group consisting of volcanic strata. They can be in the form of volcanic field A volcanic field is an area of Earth's crust that is prone to localized volcanic activity. The type and number of volcanoes ...

in southwest-central

Yukon Yukon (; ; formerly called Yukon Territory and also referred to as the Yukon) is the smallest and westernmost of Canada's three territories. It also is the second-least populated province or territory in Canada, with a population of 43,964 as ...

, Canada, located between the communities of

Dawson City Dawson City, officially the City of Dawson, is a town in the Canadian territory of Yukon. It is inseparably linked to the Klondike Gold Rush (1896–99). Its population was 1,577 as of the 2021 census, making it the second-largest town in Yuko ...

and

Whitehorse Whitehorse () is the capital of Yukon, and the largest city in Northern Canada. It was incorporated in 1950 and is located at kilometre 1426 (Historic Mile 918) on the Alaska Highway in southern Yukon. Whitehorse's downtown and Riverdale areas ...

. It consists of

flood basalt A flood basalt (or plateau basalt) is the result of a giant volcanic eruption or series of eruptions that covers large stretches of land or the ocean floor with basalt lava. Many flood basalts have been attributed to the onset of a hotspot reac ...

s, coarse volcaniclastic rocks and sandy

tuff Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is lithified into a solid rock. Rock that contains greater than 75% ash is considered tuff, while rock ...

s interbedded with

subordinate A hierarchy (from Greek: , from , 'president of sacred rites') is an arrangement of items (objects, names, values, categories, etc.) that are represented as being "above", "below", or "at the same level as" one another. Hierarchy is an important ...

andesite Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predomina ...

and

basalt Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% of a ...

ic lava flows. It has been interpreted to be a displaced portion of the

Yellowstone hotspot The Yellowstone hotspot is a volcanic hotspot in the United States responsible for large scale volcanism in Idaho, Montana, Nevada, Oregon, and Wyoming, formed as the North American tectonic plate moved over it. It formed the eastern Snake Riv ...

track that was formed 70 million years ago.

References

Hotspot volcanism Volcanism of Yukon Cretaceous volcanism Volcanic groups Flood basalts Yellowstone hotspot {{Canada-geology-stub

See also

References