Sinkhole appears in woodland
A dog walker came across the hole in Northumberland woodland, which is possibly linked to old mines.
BBC News
A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are also known as shakeholes, and to openings where surface water enters into underground passages known as ponor, swallow hole or swallet. A cenote is a type of sinkhole that exposes groundwater underneath. Sink and stream sink are more general terms for sites that drain surface water, possibly by infiltration into sediment or crumbled rock.
A dog walker came across the hole in Northumberland woodland, which is possibly linked to old mines.