Vale has confirmed that last night’s rumble was, in fact, a result of a crown blast.
The 3.0 MN seismic event occurred at 9:45 p.m. on the 5200 level at Garson’s Mine.
All employees working that evening were safely brought to the surface and all day shifts have been cancelled while underground assessments are being conducted.
Update: April 25, 9 a.m.
The shallow depth of this evening's seismic event near Garson suggests the incident is mining related, Natural Resources Canada said tonight.
In a followup email, Stephen Crane said the depth of the seismic event was located at a depth of zero kilometres, which wouldn't be unusual for it to be linked to mining activity. Earlier tonight, Crane said the event was located near Garson.
Update: 10:40 p.m. - Natural Resources Canada confirmed a 3.0 MN seismic event this evening at 9:44 p.m. tonight.
Stephen Crane, with NRC's Canadian Hazards Information Service, said the event was shallow and centred near Garson.
The rumble was felt at around 9:45 p.m. Queries from moderators on both the Valley East Facebook page and the Sudbury.com Facebook page quickly racked up hundreds of comments, as people report rumbles in Capreol, Hanmer, Copper Cliff, New Sudbury, Ramsey Lake Road, Garson, Falconbridge, along Paris and Regent streets, and throughout downtown.
People describe the rumble as lasting for several seconds to up to a minute, with several people saying they felt aftershocks. In the comments, people describe loud rumbling, their houses shaking, rumblings under the house, and objects shaking and swaying. Others describe it as though something crashed into the house or a nearby train derailment. Several people described feeling waves or vibrations.
One commenter in Lively said tonight's event was not as powerful as the seismic event that shook the city on Thursday morning.
On April 23, Earthquakes Canada reported a 3.6MN seismic event at 3:10 a.m.
The seismic event was centred about three kilometres from Lively at a depth of about 2.4 kilometres. Stephen Crane, a research scientist with Natural Resources Canada, called the seismic event “mining related,” and said it was associated with Vale’s Creighton Mine.
