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ramonmercado Psycho Punk
Joined: 19 Aug 2003 Total posts: 17938 Location: Dublin Gender: Male |
 Posted: 15-10-2011 18:54 Post subject: |
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| Quote: | The strange rubbing boulders of the Atacama
http://www.physorg.com/news/2011-10-strange-boulders-atacama.html
October 11th, 2011 in Space & Earth / Earth Sciences
These are huge boulders in Chile’s Atacama desert which appear to be rubbed very smooth about their midsections, leading University of Arizona geologist Jay Quade to wonder what could cause this in a place where water, Earth’s most common agent of erosion, is as almost nonexistent. Credit: Image courtesy of Jay Quade.
A geologist's sharp eyes and upset stomach has led to the discovery, and almost too-close encounter, with an otherworldly geological process operating in a remote corner of northern Chile's Atacama Desert.
The sour stomach belonged to University of Arizona geologist Jay Quade. It forced him and his colleagues Peter Reiners and Kendra Murray to stop their truck at a lifeless expanse of boulders which they had passed before without noticing anything unusual.
"I had just crawled underneath the truck to get out of the sun," Quade said. The others had hiked off to look around, as geologists tend to do. That's when Quade noticed something very unusual about the half-ton to 8-ton boulders near the truck: they appeared to be rubbed very smooth about their midsections. What could cause this in a place where Earth's most common agent of erosion -- water -- is as almost nonexistent?
About the only thing that came to mind was earthquakes, said Quade. Over the approximately two million years that these rocks have been sitting on their sandy plain perhaps they were jostled by seismic waves. They caused them gradually grind against each other and smooth their sides. It made sense, but Quade never thought he'd be able to prove it.
Then, on another trip to the Atacama, Quade was standing on one of these boulders, pondering their histories when a 5.3 magnitude earthquake struck. The whole landscape started moving and the sound of the grinding of rocks was loud and clear.
"It was this tremendous sound, like the chattering of thousands of little hammers," Quade said. He'd probably have made a lot more observations about the minute-long event, except he was a bit preoccupied by the boulder he was standing on, which he had to ride like a surfboard."The one I was on rolled like a top and bounced off another boulder. I was afraid I would fall off and get crushed."
He managed to stay atop his boulder, of course, and became thoroughly convinced that the earlier hypothesis about the boulders was correct.
"I was just astonished when this earthquake came along and showed us how it worked," Quade said. Quade will explain the phenomenon on Tuesday, 11 Oct. at the annual meeting of the Geological Society of America in Minneapolis.
The whole story appears to be that the boulders tumbled down from the hills above -- probably dislodged by earthquakes. They accumulated on the sand flat, with no place else to go. Quade compares the situation to a train station where people are crowded together closely, rubbing shoulders as they waiting for a train. In this case the boulders have been stuck at the station for hundreds of millennia and the train never comes. So they just get more crowded and rub shoulders more over time.
Analyses of the boulder top surfaces suggest that they have been there one to two million years. That age, combined with the fact that seismic activity in the area generates a quake like that Quade witnessed on the average of once every four months, suggests that the average boulder has experienced 50,000 to 100,000 hours of bumping and grinding while waiting for that nonexistent train.
"It also answers a mystery that had been eating at me for years: How do the boulders get transported off the hills when there is so little rain," Quade said. "How do you erode a landscape that is rainless?"
Again the answer is seismic activity.
"It raises the question in my mind of other planets like Mars." If there is seismic activity, even from meteor impacts, might it also be creating similar landscapes? "I would predict that these kinds of crowds of boulders might be found on Mars as well, if people look for them."
More information: http://gsa.confex.com/gsa/2011AM/finalprogram/abstract_188948.htm
Provided by Geological Society of America |
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| Obake Yeti Joined: 07 Jul 2009 Total posts: 63 Gender: Unknown |
| Posted: 10-06-2013 14:28 Post subject: |
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This is quite odd. I'm almost tempted to get out the conspiracy-colored, secret-weapons-testing-in-the-outback glasses:  
| Quote: | Earthquake rocks Northern Territory's southern region
By Gail Liston
Territorians are reporting cracked footpaths and shaking buildings after a magnitude 5.7 earthquake rocked the southern region overnight.
The epicentre of the quake was just 40 kilometres from the Aboriginal community of Ernabella.
Les Smith from the Kulgera Roadhouse said locals were shaken awake by the tremors.
"We've only got a couple of cracks actually in our cement paths going over towards the rooms," Mr Smith said.
"One of the local blokes who came (out) of his room, he said he saw a couple of the staff quarters shaking, so we'd better bolt them down."
The shaking has caught the interest of seismologists, because the area had a similar quake a year ago, but, before that, it had gone decades without one being recorded.
Seismologist Spiro Spiliopoulos from Geoscience Australia said the quake hit just before midnight, about 315 kilometres southwest of Alice Springs.
He said Ernabella suffered an earthquake of a similar size in March last year.
"We had aftershocks following the Ernabella (earthquake), and, likewise, we'd expect to have aftershocks from this one normally but they're typically much smaller than the big one and just last for days and weeks after the earthquake," Mr Spiliopoulos said.
He said, before these two similar-sized events, it had been more than 50 years since a quake was recorded in the area.
"It's unusual to get two large earthquakes within 40 kilometres of each other within Australia," Mr Spiliopoulos said. |
http://www.abc.net.au/news/2013-06-10/quake-strikes-territory-outback/4743686?section=nt
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| gncxx King-Size Canary
Great Old One Joined: 25 Aug 2001 Total posts: 13561 Location: Eh? Gender: Male |
| Posted: 10-06-2013 19:35 Post subject: |
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| Wasn't there a huge explosion registered in the Australian Outback a few years ago and nobody knew what had caused it? Could this be something similar? |
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| Mythopoeika Boring petty conservative
Joined: 18 Sep 2001 Total posts: 9109 Location: Not far from Bedford Gender: Unknown |
| Posted: 10-06-2013 20:11 Post subject: |
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| gncxx wrote: | | Wasn't there a huge explosion registered in the Australian Outback a few years ago and nobody knew what had caused it? Could this be something similar? |
I think there was a theory that Aum Shinrikyo had something to do with that. |
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| Obake Yeti Joined: 07 Jul 2009 Total posts: 63 Gender: Unknown |
| Posted: 11-06-2013 04:59 Post subject: |
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Interesting. Even though I imagine that the seismic 'signatures' for an earthquake, nuclear explosion, asteroid impact, etc. are different from one another, and so someone would pick up on it if there was something truly hinky, it should also be noted that this last event happened at the rare/shallow depth of 1.1km, practically on the surface of the earth, geologically speaking.
http://www.gdacs.org/Earthquakes/report.aspx?eventid=125193&episodeid=125196&eventtype=EQ |
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| Eve11 Grey Joined: 07 May 2012 Total posts: 20 Gender: Unknown |
| Posted: 11-06-2013 15:55 Post subject: |
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| There's a lot of fracking goes on in Australia inc near Ernabella, and its known to cause earthquakes. Probably suspect no.1 for any unusual seismic activity in that area. |
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| Obake Yeti Joined: 07 Jul 2009 Total posts: 63 Gender: Unknown |
| Posted: 11-06-2013 20:33 Post subject: |
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| Fracking is a very good suggestion. Of course, I don't think it can be completely ruled out that they are genuine, anomalous earthquakes, though perhaps somehow related to the fairly intense period of global seismic activity the earth has been in since December 26, 2004. |
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| eburacum Papo-Furado
Great Old One Joined: 26 Aug 2005 Total posts: 1587 Gender: Unknown |
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| Obake Yeti Joined: 07 Jul 2009 Total posts: 63 Gender: Unknown |
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| ramonmercado Psycho Punk
Joined: 19 Aug 2003 Total posts: 17938 Location: Dublin Gender: Male |
| Posted: 15-06-2013 01:08 Post subject: |
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| Mythopoeika wrote: | | gncxx wrote: | | Wasn't there a huge explosion registered in the Australian Outback a few years ago and nobody knew what had caused it? Could this be something similar? |
I think there was a theory that Aum Shinrikyo had something to do with that. |
 THat would make them into real Bond villains. |
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