Horseshoe Canyon Formation

Horseshoe Canyon Formation
A forest fire in an upland forest of the Horseshoe Canyon Formation as seen in the fifth segment of Forests
Location
Supercontinent	Laurasia
Continent	North America
Country	Canada
Unit of	Edmonton Group, Western Canada Sedimentary Basin
Region	Alberta Province
Temporal Range	74 - 67 million years ago, Campanian - Maastrichtian Stage, Late Cretaceous Period
Episodes	Forests (Segment 5)
Characteristics
Climate	Temperate
Environment	Estuarine, Forest, Floodplain, Swamp

“ In the forests of North America, there is an additional annual hazard for forest-dwellers. Fire, started by a strike of lightning. As it spreads, temperatures rise to over 2000 degrees Fahrenheit. The flames rise several hundred feet into the air. ”

― David Attenborough, Forests

The Horseshoe Canyon Formation is a stratigraphic unit of the Western Canada Sedimentary Basin in southwestern Alberta. It takes its name from Horseshoe Canyon, an area of badlands near Drumheller.

Because of the presence of Edmontosaurus regalis, it is possible that the unit represented on Prehistoric Planet is either the Drumheller or the Horsethief Member, for E. regalis is only known from the lower, earlier layers of the Horseshoe Canyon Formation, as it appears to have been replaced by Hypacrosaurus altispinus in the upper portions, with its disappearance (and the apparent absence of ceratopsians in those later times) being attributed to possible climate change.

Paleoenvironment

The Horseshoe Canyon Formation is a region of various environments that range from the Late Campanian to the Early Maastrichtian stage of the Late Cretaceous Period, with evidence indicating the existence of estuaries and floodplains periodically covered up by the sea.

“ This may look catastrophic. But remarkably, some plants must be burned if they are to complete their life cycle. The intense heat is needed to open the cones of the pine trees, and release their seeds. And only a few hours after the fire has passed, animals begin to return. Beetles are among the first. They start to lay their eggs. When they hatch, the larvae will be the first to feast on the near-limitless supply of dead wood. ”

― David Attenborough, Forests

Coal swamps in the Horseshoe Canyon Formation indicate that the area also had riparian (waterside) forests which were at constant risk of forest fires, hence, some of the native plants evolved specifically to exploit these constant events and complete their life cycle, and some of the animals even take advantage of the resources offered by recently-burned forests.

Paleofauna

Anodontosaurs lambei

Atrociraptor marshalli

Edmontosaurus regalis

Appearance

A burnt forest in the Horseshoe Canyon Formation serves as the main setting of the fifth segment of Forests, showing the dangers that forest inhabitants face beyond predators, and how the wildlife has adapted to survive and take advantage of such events.