When the side of the volcano doesn't halt in such circumstances and instead slips off into the ocean, a so - called flank collapse occurs. (scientificamerican.com)
If at the end of that two minute monitoring period, the price is still at the limit down or limit up, a two minute halt on trading will begin. (links2exchange.net)
I've seen potty training halt for months over a child slipping off the seat and their bottom hitting the water. (verywellfamily.com)