underground

Sinkholes can be formed by gradual dissolution happening underground, but they can also be caused by heavy rain or surface flooding, construction work, leaking drainage pipes, burst water mains and groundwater abstraction, the BGS said.

"It's refreshing that someone's going to the underground for new sounds," he says.

Renovation work at Notre-Dame has been a boon for archaeologists, who have been able to access underground areas that date back to hundreds of years before the cathedral was built.

Nearly $20 million will go to electrify the university’s BruinBus fleet and install underground charging for shuttles and buses along a route that stretches for less than a mile in Westwood.

It happened close to where an underground natural gas leak occurred in July following the installation of a ground source heat pump.