The natural gas wells have nearly same metrics that oil wells do. I have long studied the effects of fracking and SWD related earthquakes and so far as I have seen there is no correlation other then SWD.
Since all measurable quakes are so small it is concluded (based on the research I have seen) that it is small fault blocks that effectively get lubricated which allows for small releases of stress on faults instead of build up to larger events.
You will see gas mixed with water in certain parts of the country. This is naturally occurring and has been well known to locals for decades before fracking was even put into use.
Now chemicals being used in the ground should always have strong oversight and be diligently handled. There is no excuse for poor responsibility regardless if there are no to minimal examples.
Just my two cents!
Purely My Own Opinion. Do Your Own Due Diligence.
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