A 1.5 magnitude tremor stopped fracking at Cuadrilla’s shale gas exploration site in Preston New Road, Lancashire.
According to Cuadrilla Resources, the 1.5 magnitude tremor occurred today (Monday 11 December|) at about 11.20 am. The British Geological Survey’s website had registered a series of micro seismic events this morning at the site.
Cuadrilla Resources is an oil and gas exploration and production company with headquarters in Bamber Bridge, Lancashire. It intends to develop shale gas in the United Kingdom using hydraulic fracturing.
According to Cuadrilla, the 1.5 magnitude tremor occurred after the hydraulic fracturing had been completed for the day.
In a press release, Cuadrilla wrote:
“According to recent research by the University of Liverpool, the impact would be like dropping a melon. A series of smaller micro seismic events occurred during hydraulic fracturing, beginning at about 9.40am.”
Tremor stopped fracking for 18 hours
The company says that it will pause and continue monitoring micro seismicity for the next 18 hours (at least). This wait conforms with the government’s traffic light system.
Government’s traffic light system
In the government’s traffic light system, a 1.5 tremor is a ‘red’ light.’ There are three colours:
- Red – magnitude of at least 0.5. The operator must suspend injection, reduce pressure, and monitor seismicity and ground motion for any further events before resuming work.
- Amber – magnitude zero to 0.5. Injection can proceed, with caution, and maybe at reduced rates. There is more intensive monitoring.
- Green – magnitude zero. Injection can proceed as normal.
1.5 magnitude tremor shook resident’s house
BBC News interviewed Cath Middleton who lives 1.6 miles from the fracking site. She said that she heard a ‘very loud bang’ and that her house shook.
Ms. Middleton said:
“To compare this to dropping a melon is ridiculous. My neighbour’s chair shook.”
In October this year, there were two tremors within a 24-hour period. The first one, a 0.76 magnitude tremor, suspended all operations. The second was a 0.5 magnitude tremor. Both were ‘red events.’