Sand can sing! When a family dropped by Crossroads after a visit to Lake Michigan, the kids reported a strange phenomenon. The young people explain that when they walked along the beach and dragged their feet, the sand felt funny and it made a squeaky noise.
I was lucky when I moved to Door County and first noticed singing sand. A friend loaned me an article put out by the Indiana Department of Natural Resources. According to its author, John R. Hill, the squeaking only happens on a certain part of the beach—a band 25-100 feet wide. This band runs parallel to the shore.
When kids (or kids at heart) drag their feet or push an object through the sand, , the tiny grains rub against each other. This makes a vibration which we can hear.
“Why doesn’t all sand squeak, including the sand on a dune?” Mr. Hill asks in this article, and then he answers his own question [He must be a teacher] “The sound only happens when each grain of sand is covered with a thin film of water.”
If the sand is dry, the singing won’t happen. It won’t happen if the sand is really wet either. Sand on a dune is too dry and the sand right at the shoreline, where waves break–it’s too wet. [Why does this remind me of Goldilocks and the Three Bears?] Anyway, just beyond the wave-wash zone, the sand is “just right.”
Apparently, when a wave breaks, little droplets settle on the sand. Spray causes just enough moisture to make sand sing.
But the sand on our Lake Michigan shoreline is not quite the same as the perfectly round, inert silica sand that comes from the 500-million-year-old Jordan sandstone formation of central and western Wisconsin. Silica sand has been used for thousands of years for water filtration, glass manufacture, industrial casting, sand blasting and to make concrete.
According to the Wisconsin Department of Resources, “Sand mining has occurred in Wisconsin for more than 100 years. Recent growth in the petroleum industry has created a high demand for sand that can be used for hydrofracking, a technique used to extract natural gas and crude oil from rock formations in other states. Wisconsin has high-quality sand resources and, as a result, the DNR has seen a substantial rise in permit requests to the department to mine for silica or “frac” sand.
The extracted sand is often processed locally. Processing of the sand typically involves washing and separating the sand into grain sizes suitable for hydrofracking. The sand is then shipped out of state for use at gas and oil fields for hydrofracking.”
On Wednesday, June 11, at 7:00, the Door County Environmental Council will present the documentary, “The Price of Sand” which features frac sand mining and tells the stories of the families who live near sand mining and processing operations. The public is invited to view this film to gain an understanding of this controversial practice.
The Door County Historical Society will open their Heritage Village at Big Creek on Sunday, June 15.
The Village opens with a Band Concert and Ice Cream Social. The Peninsula Symphonic Band, a 50 member ensemble under the direction of Paula Eggert, will play a variety of popular tunes beginning at 2:00. Tours of the Village will be offered between 1:30 and 3:30.
During the summer season, Joan Wilkie, the Crossroads Summer Educator, will offer family programs Monday-Thursday at 10:00. Because the 2014 Educational Theme of Crossroads is “Below the Surface”, this year’s programs will explore a variety of subterranean topics. Monday, June 16 the program will be “Underground Detectives” and Tuesday, June 17, “Fossils Beneath our Feet“. All are welcome (you need not bring a family). Summer programs are made possible with a grant from the MMG Foundation and are free and open to the public.