I live in NE Oklahoma - to the west of Tahlequah, and SE of Tulsa.

I work most days and cannot hear the booms inside.

But when I am home and outside, I hear them often. This past Saturday (2/15/14) I heard 3 and the last was around sunset and SUPER loud. Many will cause the ground to shake and this one did as well, but was even louder than most.

They sound like artillery or cannon booms. Not like a sonic boom (heard plenty of them in my youth growing up near Tinker AFB, before they were banned).

They seem to come from the ridge to the NW of us, and not from the sky. I have never seen military jets associated with them.

If I am in contact with the ground, I feel a mild shaking with most booms.

To my knowledge, there are no quarries or blasting sites nearby. We live on a major tributary of the Illinois river and the area derives much of it's commerce from agriculture and tourism. Few oil/gas wells, and little current drilling in the area. No known fracking as is common in central, SE and Western OK.

Very puzzling. I grew up in Central OK and have lived in various parts of the State. Never have experienced these booms before the past 2 years. Increasing infrequency as well.

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