A line in the sand: Workers plant a web of shrubs in the desert to halt the advancing of sand dunes

Xinjiang, in Northwest China, is home to the country's biggest deserts. Fighting desertification is a constant for cities deep in the region, to avoid the fate of being buried like the ancient Loulan civilization more than 1,600 years ago.

The town of Qiemo, in the middle of the Taklimakan Desert, China's largest, has been fighting against the sand dunes pushing towards it. On the other side of the Qarqan River, the sand dunes are only two kilometers away at the nearest point. Three times in the town's history, the river running through it was diverted by shifting desert sands................the article and more images to...(Global Times)
23/10/14

Using sand for fracking: pros and cons

Disputes about pros and cons of fracking are still going on in the US, especially in Midwestern states. Although there are no fracking facilities in some Midwestern states, these states are now experiencing a big increase of the sand mining industry. The reason is that the process of fracking needs large amounts of sand.
The Christian Science Monitor describes the process as follows: “To extract the sand, mining companies scrape away the soil, break up the sandstone with explosives, and then crush it. The raw sand is washed, sorted by size, and shipped by truck, rail, and barge to fracking operations in the US and Canada. There the sand is mixed with water and chemicals and pumped underground, where the particles lodge in cracks and prop them open while gas or oil flows out.”

Oil and gas companies need the sand used in fracking operations to hold open cracks in shale rock. In Ohio, that rock is usually the Utica formation. In West Virginia and Pennsylvania, it’s the Marcellus shale.

Much of that sand is ripe for mining in upper Midwestern states such as Iowa, Illinois, Minnesota and especially Wisconsin.

Sand has long been used in various branches of industry in these states, but it has never been taken in such large amounts until the fracking method started to be used for extracting oil in gas in this area four years ago.

Local residents have various opinions about that. Some are claiming that the industry is ruining the once-idyllic land.

“Since 2012, Wisconsin has found nearly two dozen sand-mining operations in violation of air and water pollution rules,” an article in the Christian Science Monitor says.

Voice of Russia, bizjournals.com
 http://voiceofrussia.com/news/2014_03_12/Using-sand-for-fracking-pros-and-cons-3382/
12/3/14
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Related:

• More than 30 earthquakes hit Texas towns after start of fracking 

• Study links fracking with methane-contaminated drinking water (+2video RT)

• Shale revolution a la Russe: Shell, Gazprom Neft start fracking in Siberia

• Günther Oettinger: Wir brauchen in Europa die Option des Fracking“.

• Ukraine’s Shale Gas Plans Pose Danger for Russia – WWF. -Russia cannot compel Ukraine to present an international assessment of the project’s risks because Russia has not ratified the United Nations’ Espoo Convention.

 

Video: Grains Shape the Songs of Sand Dunes

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When plagued by whipping desert winds, sand dunes signal their displeasure with haunting moans that reverberate across the arid landscape. Some emit single-note songs while others mimic a jumbled chorus—but no one knew why they sang these different songs until now.
New research published online this week in Geophysical Research Letters finds that the size of sand grains shapes a dune's song.
 Scientists collected sand from a singing dune in Morocco that moans at around 105 hertz (Hz)—or, to a musician, that's G-sharp two octaves below middle C. They compared these notes to sounds from sand collected from a dune in Oman, which produces notes ranging from 90 Hz to 150 Hz (F-sharp to D). By creating mini-dune avalanches in the lab, scientists recreated these desert songs, finding that different layers of sand aren't necessary to produce the moans, as previous researchers contended. They also found that when they sieved the Omani sand so that the grains were similarly sized, the resulting "avalanche" produced a single-note song. The synchronized movement of sand grains, they conclude, produces the famed moaning, while grain size determines the notes contained in the song.
 .sciencemag.org
26/10/12