Earthsky today links to a new USGS report on “induced seismicity” linking earthquakes to human activity. As I read the report and negotiated my way through the thickets of tortured syntax and the brambles of labored locutions, there is a lot less here than meets the eye. I also conclude that this has more to do with political geology than physical geology. Here is a sample pull quote from the report:
“Conclusions of the workshop and meeting indicated that induced earthquakes are difficult to include in probabilistic seismic hazard analysis because the hazard is (1) highly variable spatially and temporally, (2) dependent on human economic or societal decisions regarding when to initiate or terminate wastewater disposal and how much fluid (volume) would be injected or extracted, (3) conditional on understanding differences between source and ground shaking characteristics of induced and natural earthquakes, and (4) dependent on the length and depth extent of the causative faults, which are generally unknown. For this 2015 sensitivity study, we redefine the 2014 zones based on locations of earthquakes that have been attributed to human activities such as wastewater injection and hydraulic fracturing.”
Well, guys, let me help you out here with some plain English. What this paragraph says to me is this: We think fracking is a bad idea and we are trying hard to link it to these earthquakes, but we just can’t seem to prove it.
Not surprisingly. The problem is that probability, models, and prediction are not science. Without data, there is no science, probability is just an elegant word for wagering.
It would seem to me, for those who are opposed to fracking as a matter of public policy, a better approach would be to investigate whether or not fracking causes groundwater pollution. That might lead somewhere. We already know what causes earthquakes.