How definitive would you have to be…
…to know when earthquakes are caused by an injection well? In Greeley, increased volumes and pressures at a well were nearly immediately followed by earthquakes at and below the well that increased in size until one was felt. When the well was shut down, seismicity backed down. As the well was returned to service, some seismicity recurred.
According to the Colorado Oil and Gas Commission as reported in the Denver Post, this indicates that
any connection between the Greeley quake and the injection well remains in the “not definitively caused by” category
GG notes that such a close temporal and spatial correlation would put the well in the “almost certainly the cause of seismicity” category. Evidently science speak and lawyer speak use words differently.
While COGC speaks with forked tongue to avoid alienating the oil and gas industry, they have acted quite responsibly in this matter, especially compared with some other organizations farther south.