Steen River is an impact structure in Alberta, Canada. It is 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 of sediments.
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.