Two of those have been powerful enough to exceed a regulatory threshold that requires fracking to stop, and on a third occasion the company voluntarily ceased operations when it neared the limit.
Cuadrilla didn't expect this level of seismicity:
During a tour of the site in June, Matthew Lambert, the government and public affairs director at Cuadrilla, said: "Because we are managing that risk I don’t really accept that we are likely to cause seismicity above that level [an apparent reference to 0.5-magnitude] and we will not be causing seismicity which will damage property."
Francis Egan, the chief executive of Cuadrilla, last week urged the government to relax the regulatory threshold or risk stifling shale gas exploration.
Thankfully:
The energy minister, Claire Perry, rejected such calls, saying only a "very foolish politician" would do so at this point.
But so much for all the investigations and assurances from Cuadrilla and consultants Arup:
Which is plainly over-egging it somewhat, based on the 37 quakes in three weeks.
It's another example of the fallibility of consultants, about which we know all too well with Straitgate – a site incidentally which has had consultants struggling with Environmental Impact Assessments far longer than "a year and a half", with still no end in sight.
Anyway, you can understand why the Green Party says Cuadrilla is "obviously in way over their heads".
Shale gas developers could be required to consult local communities, even before submitting a planning application, following the launch of the latest government consultation.
Those with an interest have until Monday 7 January 2019 to respond.