The range of 60-70 decibels sound pressure level is about as loud as normal conversation in 1 meter distance. The distance from the ears to the sound source is very important to the value of the SPL. Scroll down to related links and look at Table of Sound Pressure Levels.
1 Primarily, during the fracking process:  [Earthquakes] were caused by fluid injection during hydraulic fracturing in proximity to pre-existing faults.. 2  Secondarily, via the disposal of fracking wastewater via underground injection.
Drilling companies suggest trillions of cubic feet of shale gas may be recoverable from underneath parts of northern England, through a process known as fracking. Hydraulic fracturing, or fracking, is a technique designed to recover gas and oil from shale rock.he extensive use of fracking in the US, where it has revolutionised the energy industry, has prompted environmental concerns. The first is that fracking uses huge amounts of water that must be transported to the fracking site, at significant environmental cost.