Friday, April 15, 2016

Georgia’s “Secret” Volcanic Range

For reasons that escape me, this string of volcanoes has never received proper publicity and academic recognition.  Yet every school child should know and have at least a field trip to remember.  How better to teach geology?
The mineral occurrences are at least known but missed out on the big exploration binges so far as i know.  This was likely the result of title issues and poor government policies not unlike the current situation in the USA today.  Modern technology will change all that but lower grades will likely leave this mineral district dormant.
In the meantime it is also evident that this supported native mining activity before contact as well.
The chain itself likely represents the activity associated with one hot spot alone as the crust was dragged over it in an east west direction.  Regardless it is not extinct at all and has a poorly estimated potential for mischief. 
Georgia’s “secret” volcanic range

April 2, 2016 Richard Thornton 2 Comments

POOF member, Suzanne Ward, mentioned the volcanic cones in the Pigeon Mountain Volcanic Range. Virtually nobody knows about this unusual geological feature in the Southeast . . . even the state’s geology professors seem to be unaware of it. I called the directors of the geology departments in Georgia’s three largest public universities. None of them knew much about the geology of the North Georgia Mountains and didn’t even know that the volcanic cones were there.

The Pigeon Mountain Volcanic Range is located west of Lafayette, GA and east of Lookout Mountain. The dormant volcano on the right last erupted in 1857. The only reason I know is that there are frequent tremblers under Pigeon Mountain. It is dormant and last erupted in 1857. The frequent little earthquakes trigger the “Earthquake Code” requirements of the International Building Code. I telephoned the professors so that I could get more specific information on the amount structural reinforcement, my buildings needed. They were no help at all.

The generally extinct line of volcanoes begin at Curahee Mountain near the Savannah River and are aligned roughly East-West across the state. They cross the Blue Ridge Mountain Range and have distinctly different shapes than the Blue Ridge Mountains. They are the source of the gold, copper, ruby, sapphire, garnet and diamond deposits in North Georgia.

Collapsed calderas

Calderas are especially large volcanic basins. There are several ancient collapsed calderas in North Georgia. We know of three that contain complexes of Native American tombs. They are often called caves by the local mountaineers, but were hand dug for burials. This is what a collapsed caldera looks like on a topographic map.

No comments: