It looks like you're using an Ad Blocker.
Please white-list or disable AboveTopSecret.com in your ad-blocking tool.
Some features of ATS will be disabled while you continue to use an ad-blocker.
Originally posted by Scaledown
As noted in the Map thread it has also been heard in the UK and Canada.
Since I don't know much about US geography is there a mountain range or known ancient volcanic activity in the eastern states?