Ancient Earth History revealed - a giant scar under the American Midwest

[Retread]

https://source.wustl.edu/2016/09/a-terrible-rift/

The farmers in Minnesota have a point when they wonder what an “earthquake sensor” could detect in an area where there are no earthquakes. The answer is that the seismometers record distant earthquakes, such as those on the Pacific Ring of Fire on the opposite side of the planet, and ambient noise, caused by activity such as powerful storms slamming into the Jersey Shore.

[jinxmchue]

Back in 2011, there was a 2.5 earthquake near where I live in Minnesota. It happened at 2:20 a.m., though, and I slept right through it. Other people around the area reported experiencing it, though. It was pretty big news given the rarity of earthquakes in the upper Midwest. Had this happened in California, the response would be like the restaurant scene from "L.A. Story."

[cadillac shark]

https://source.wustl.edu/2016/09/a-terrible-rift/

The farmers in Minnesota have a point when they wonder what an “earthquake sensor” could detect in an area where there are no earthquakes. The answer is that the seismometers record distant earthquakes, such as those on the Pacific Ring of Fire on the opposite side of the planet, and ambient noise, caused by activity such as powerful storms slamming into the Jersey Shore.

America's low-frequency radar HQ for both oceans was located in Michigan's Upper Peninsula for decades. -Goes through bedrock like it doesn't exist. It was also used for submarine-communication via low-megahertz radio transmitting.

The info became 'public' when people began complaining about mysterious humming that would constantly occur for no apparent reason.