Ringing rocks

Ringing Rocks is a phenomenon where rocks have the curious property of resonating like a bell when struck with a hammer or other object. One such place where this can be observed is in Ringing Rocks Park located near Bridgeton, Bucks County, Pennsylvania USA. Ringing rocks are also known as sonorous rocks or lithophonic rocks, as used in musical instruments such as the lithophone.

Ringing Rocks Park

According to the unmuseum, "In 1965 a geologist named Richard Faas from Lafayette College in nearby Easton, Pennsylvania, took a few of the rocks back to his lab for testing. He found that when the rocks were struck they created a series of tones at frequencies lower than the human ear can hear. Only because the tones interact with each other is a sound high pitched enough to be audible generated. Though Faas's experiments with the rocks explained the nature of the tones he was unable to figure out the specific physical mechanism in the rock that made them, though scientists suspect it has something to do with stress within the rocks." [http://www.unmuseum.org/ringrock.htm]

Bell Rock Range

The Bell Rock Range is a large ultramafic gabbro-peridotite intrusion in the Musgrave Block of Western Australia, near Warburton. It is composed of massive, heavily indurated intrusive rocks and forms a prominent 15 kilometre long range of mountains and hills.

The intrusion is called the Bell Rock Range because, when struck, the rocks ring like a bell.

ee also

*Basalt
*Diabase
*Granite

Bibliography

*James Pontolillo and John Pontolillo, 1993, "Ringing Rocks Sites in Pennsylvania and New Jersey", INFO Journal #68. [Comprehensive review of all known ringing rock sites in PA and NJ.]

External references

* [http://www.unexplainedearth.com/ringing.php Unexplained Earth: Ringing Rocks of Pennsylvania]
* [http://www.philageo.org/features.html#_Ringing_Rocks Ringing Rocks, Lower Pottsgrove Township, PA]
* [http://www.billingsgazette.net/articles/2007/07/02/news/state/32-rings.txt Ringing Rocks in Montana]