Reply #32: I can't answer that question. It could, if the injected fluids were

[MineralMan]

in an actual fault zone. At least it could on a theoretical basis. But, the small tremors associated with fracking are much more localized than that. Any time you start cracking underground layers, you can have some localized tremors. That's been demonstrated for years with the use of injection to increase yields from oil wells. Similarly, removing large amounts of water from deep aquifers also can trigger localized earth tremors. These are not associated with seismic fault zones, though, but are cause by local failure of structures.

Even quarry blasting can cause localized tremors in the 2-3 magnitude range. That has occurred in many areas. None of these, however, involve seismic faults, but are merely localized effects.

Studies were done, and experiments made in the 50s and 60s and perhaps later, to test the idea of injecting fluids directly into seismic faults, with the idea of relieving built up stresses smoothly. Generally, this idea was abandoned as impractical. Some minor tremors did result from those experiments.

Fracking is generally used to fracture limestone and shale structures, not bedrock structures where seismic faults exist. The goal is to crack structures that hold natural gas so the gas can be released and utilized. Earthquake faults do not generally originate in those structures, although those structures may reflect the existence of earthquake faults in other structures.

It's all pretty complicated, and I can't really fully explain the whole thing in DU posts. It's easy enough to research, though. Google will find tons of information on fracking and earthquakes and fault-zone geology. If you have a couple of weeks to devote to learning about this, you can educate yourself pretty well, as long as you stick with sites that are fact-based and not get distracted by woo sites. It's all very interesting, and you could spend years learning about it. That's what I've done. Geology and plate tectonics have been a strong interest of mine since the 1960s, so I've read extensively in the area and even was in a business that required a lot of geological knowledge.

It's too complicated to deal with in short messages.