If you heard what sounded like a loud explosion on Bell Island on Good Friday, you weren't the only one -- and the potential explanation for the noise might surprise you.

Henry Crane thinks the noise hundreds, possibly even thousands, heard was a large "junk" of rock from the north side of Bell Island, cracking off and falling to the water and ground below.

"It is an extensive pile of rock that fell in. I'd say you are in the thousands of tonnes that fell down," Crane, who is from Bell Island, said about the massive rock collapse.

"Apparently up in the west mines, near the Scotia No. 1 mine area where the Grebe's Nest is, people's houses shook, and their tables shook," he said.

Another picture taken a few days after the collapse shows more cracking and fractures on the top of the land. (Henry Crane)

That unexplained shaking happened at about 4 p.m. on the Friday of the long weekend, and it wasn't just people on Bell Island who felt the ground move underneath them. The impact of the rock hitting the land below was felt from Topsail Pond Road around Conception Bay, as far as Harbour Grace.

'Only a matter of time'

Mary Delaney, also from Bell Island, was at work when the collapse happened.

"I was talking to my sister because I called her from work and she said it was around supper time on Friday, they heard what they thought was thunder. then the floor underneath her kind of shook," Delaney said.

"They didn't know it was a collapse until the next day ... there is nothing there now but landslide," she said.

Houses shook in Hr. Grace area as well. Felt like an explosion on top of my place. —@KimberleySkin12

I did hear and feel this is Portugal Cove. Was so curious what it was - good to know!! —@tracekeough

In Manuels my house shook. I looked outside and did not hear sirens so assumed it was blasting operations near by. But i was sitting on a wooden chair and the house really shook —@igillies

Crane, who is also a town councilor, said an area of Bell Island facing the northwest, close to what people call the Grebe's Nest, collapsed. Large cracks 18 inches thick had been forming in the rock side for some years, he said.

This photo was posted a day after people reported hearing a loud noise that sounded like an explosion. (Tyrone Fillier)

"The northwestern side of the island where this fell off is shale-type rock," he said.

The area was exposed to the winds and waves pounding on it, he said, and over time the elements carved out the bottom of the rock, with a solid overhang remaining on top.

"It was only a matter of time and this was going to fall in, and of course it did."

Six years ago members of Bell Island's town council put signs up in the area warning people to stay away, Crane said, but the area remained popular for visitors and hikers.

"People had enough sense to stay away from it," he said. "They were heeding the warnings."

Bell Island is known for its iron ore deposits and its history of resource extraction and mining. Despite the recent collapse, Crane believes the overall state of the underground mines around Bell Island are stable, in part because the mines are carved in iron ore, unlike the shale that collapsed.

"There's probably seven or eight caves there and most of these now, because of this fall of rock, those caves are sealed off … you don't know what damage that did to the caves on the other side," he said.

"I'm talking thousands of tonnes of rock fell in."

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