Bernie's recording of the Kelso Dune is now posted in the group's Files.
http://groups.yahoo.com/group/naturerecordists/files/Dunes4.mp3
For some reason Yahoo wouldn't recognize Bernie's file when he tried
to upload it, so I offered to post it for him.
-John Hartog
--- In Wild Sanctuary <>
wrote:
> Dunesong is something we worked on with a group from UC Santa Cruz
> for about 7 years in the 90s as part of a team headed by the late Ken
> Norris (the fellow who discovered how dolphins echolocate and who was
> head of the Environmental Studies Dept, there). The team consisted of
> a nuclear physicist, several geologists, two naturalists, and a
> storyteller (for our evening campsites).
>
> Studies of dunesong were first initiated by Bagnole in the mid-50s
> and have been going on ever since, however intermittently. There are
> several literary references to dunesong in T. E. Lawrence's (Lawrence
> of Arabia) writings. Native Americans of the southwest have ancient
> myths that tell of the spirits hiding in the desert that speak to
> them at certain times and sites. Dunesong, because it is very low
> frequency, can often be heard 7 - 8 miles (11 - 13km) from the point
> of origin if the weather conditions are right.
>
> We measured 10 different sites in the West and Southwest (Nevada,
> California, Arizona, N. Mexico and Colorado). No one knows for sure
> what's happening since not all dunes "sing" and those that do, do not
> do it all the time. After measuring sand grain size, shape, angle of
> repose (of the slipface of the dune), surface and depth temperatures,
> accumulated moisture at different layers, and magnetite content, we
> figured that when certain grain size, shape, and magnetite and
> moisture create ideal conditions for dunes to "sing," they begin to
> resonate. Sometimes they "tire" and have to recharge before "singing"
> again.
>
> Typically, when conditions are right, a drier layer moves slowly over
> a more humid layer, which, in turn is moving at a slightly faster
> rate than the one below it. Each layer forms ridges as it moves
> downward. No one knows for sure if the movement (friction) over the
> ridges (wave forms of a physical type) causes resonance. But some of
> us think it does assuming all other conditions conspire.
>
> Two ways dunesong can be introduced: (1) naturally, when the angle of
> repose and other conditions are just right and assuming the dune is a
> "singer," and (2) by climbing all the way up to the top of the dune
> ridge and sliding down on your ass. Dunesong sounds more like a
> freight train to me - having none of the hi-freq of a jet - and can
> last anywhere from a few seconds to over three minutes. They range
> from infrasound (in the 5Hz range) to around 120Hz and each dune
> seems to have it's own range of signatures unique to that site.
>
> I've got a good example of Kelso singing if someone will walk me thru
> the process of how to post it.
>
> Bernie Krause
>
> > >To the north about 10 miles are the Kelso Dunes, one of the
> >>sites in the desert SW where you can record the dunes singing
> >>assuming conditions are right and you have the right transducers (a
> >>pair of good PZM mics or hydrophones in ziploc bags of water buried
> >>in the sand in order to get the infrasound component at around 10Hz).
> >>Best window to record is between late March and May. There's also a
> >>National Park Service visitor center north of the dunes on the
> >>Kelbaker Rd at Kelso where we've just installed a couple of
> >>soundscapes representing the desert in that area. It is scheduled to
> >>be open sometime in August of this year.
> >
> >I visited the Kelso Dunes on my way back from recording at Joshua
> >Tree National Park a couple of weeks ago. I climbed most of the way
> >up the big dune, but they weren't sayin' anything. What are the
> >conditions that produce singing?
> >
> >BTW the interpretive sign said it sounded like an airplane. I heard
> >several of those, but I wasn't fooled.
> >
> >-Dan Dugan
> >
> >
> >"Microphones are not ears,
> >Loudspeakers are not birds,
> >A listening room is not nature."
> >Klas Strandberg
> >Yahoo! Groups Links
> >
> >
> >
> >
>
>
> --
> Wild Sanctuary
> P. O. Box 536
> Glen Ellen, CA 95442
> t. 707-996-6677
> f. 707-996-0280
> http://www.wildsanctuary.com
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