Hosta

Steen River is an impact structure in Alberta, Canada. It is 25 km (16 mi) in diameter and the age is estimated to be 91 ± 7 million years (Late Cretaceous). The structure is not exposed at the surface. The original crater was partially eroded prior to burial, and lies under 200 m (660 ft) of sediments.^[1]

References

External links

• Exploration of the Steen River impact structure

Further reading

• Niccoli, M., Hildebrand, A.R. and Lawton D.C. (2005) "Seismic Velocity Study of the Rim Uplift of the Steen River Impact Crater" Lunar and Planetary Science XXXVI.