Fracking firm Cuadrilla say they've stopped fracking for the day after a 'seismic event' occurred at the Preston New Road site
The company say the tremor was 0.4 magnitude and described it as extremely low. They say they've adopted extra precautions by stopping work until tomorrow.
A spokeswoman for Frack Free Lancashire said the tremor was a "worrying sign".
The highly sensitive monitoring systems at and around Cuadrilla’s shale gas exploration site in Preston New Road have detected a seismic event within the company’s operational area (approx. 4.8km²) of 0.4 ML (Local Magnitude) this afternoon while hydraulic fracturing operations were ongoing.
This is an extremely low level of seismicity, far below what could possibly be felt at the surface but classed as an amber event as part of the Traffic Light System (TLS) in place for monitoring operational activity.
As such we are required to reduce the rate we are pumping fracturing fluid once it has been detected.
In fact we have adopted extra caution and have stopped pumping for the day.
Seismicity will, as always, continue to be monitored closely around the clock by ourselves and others and we plan to continue hydraulic fracturing again in the morning.
Local residents should be reassured that the monitoring systems in place are working as they should.
These are tiny seismic events that are being detected by our monitors as we fracture the shale rock and are not capable of being felt much less cause damage or harm.
Regulators have been informed.
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