A family in the town of Falmouth in Hants County, Nova Scotia, has been forced to flee their home after a sinkhole opened beneath it on Sunday 3 September 2017. They were awoken by noises in the house at about 4.00 am, that they assumed were due to a break-in, causing them to call the police. However when a patrol vehicle arrived the crew found a sinkhole 7 m deep and extending beneath the property, which the house was beginning to collapse into. The family have been evacuated from the property, which has had its electricity, water and sewage lines disconnected, and an oil tank on the property has been drained as a precaution. The hole appears at the current time to be contained on the one site, however residents of neighbouring homes have been warned to be prepared in case the hole spreads, which could lead to further evacuations.
House in Falmouth, Nova Scotia, undermined by a sinkhole on 3 September 2017. Anjuli Patil/CBC.
Sinkholes
are generally caused by water eroding soft limestone or unconsolidated
deposits from beneath, causing a hole that works its way upwards and
eventually opening spectacularly at the surface. Where there are
unconsolidated deposits at the surface they can infill from the sides,
apparently swallowing objects at the surface, including people, without
trace.
On this occasion the cause of the sinkhole has yet to be determined, however other sinkholes in the region are generally associated with the evaporites of the Widsor Group, Early Carboniferous deposits laid down in a series of shallow seas that became cut off from the wider ocean, the slowly evaporated, leaving extensive beds of salt and gypsum, which are easily dissolved by any water that filters thought the overlying rock and reaches them leading to rapid sinkhole formation.
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