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DUTCHSINSE zoomed in on the Utah EQ site and said it appeared a portion of the Crayton had collapsed due to fracking

I'm not aware of any fracking in the area of the earthquake.

The epicenter, and all the afterquake shocks, were about 5 miles west of the SLC airport, a mile to two south of the southern end of the Great Salt Lake, a couple miles north and northeast of Magna, and east of the northern tip of the Oquirr mountain at Lakepoint Junction.

The Air Force bombing range is to the west of the lake, about 30 miles away at the nearest point. Dugway Proving Ground is about 50 or 60 miles to the west and south, beyond the Oquirr mountain, the Tooele valley, and another mountain.

The whole area of the initial quake and aftershocks is mostly weeds, owned by Kennecott Copper mining company. There is a railway that passes through the area, but the highway (I-80) is north of all the quake points, closer to the lake. The Kennecott open pit mine is south and west of Magna, a couple miles farther from the quake sites. The county dump and landfill is to the southeast of the area.

I've driven on the highways and streets on all sides of that area, over the past 13 years, and have never seen anything resembling a drilling rig or pumping rig. I would notice, because I look around when I'm driving. That's part of the driving experience.

Closer up to the Oquirrs, there are some facilities and equipment associated with Kennecott's copper mining. I believe most of that is for open pit mining. I've talked to several people who have worked out there, and they've never mentioned any underground work there.

The big famous open pit hole is one mile deep. The quake epicenter was 10.1 km deep, about six miles down. I don't think the quake was related to any human activity.

The Great Salt Lake is the remnant of a much larger Lake Bonneville that existed until the end of the last ice age, about 12-15000 years ago. The water level was about 600 feet above the current GSL level. You can still see the water marks on the surrounding mountains in some areas. It was about the size of Lake Michigan.

So the valleys in this region are sand, gravel, limestone, and sandstone, going way down. Something farther down slipped, or dipped, and the surface material moved around a little bit. Not a big quake.