Which term describes slabs on weak layers buried by storms?

• A. Persistent slab
• B. Deep persistent slab
• C. Glide avalanche
• D. Crown

Answer: (A)

Slabs on a weak layer buried by storms are described as a persistent slab. The idea here is that a cohesive layer of snow (the slab) sits atop a preexisting, weak layer (often facets or surface hoar) that was buried by new storm snow. Because the weak layer remains buried, the slab above can remain prone to failure long after the storm, potentially propagating and causing avalanches over a broad area. This persistent weakness makes the hazard linger beyond the immediate storm period.

Glide avalanches involve sliding of a snow layer along a smooth surface beneath, which isn’t about a slab sitting on a buried weak layer. A crown is simply the fracture line or edge at the top of an avalanche, not the type of slab. A deep persistent slab is a subset of persistent slabs that refers to particularly deep failure planes; the general term for slabs on a weak layer buried by storms is persistent slab.