Author Topic: Monday 28th June 2010 - Cracks!  (Read 3923 times)

Geoff

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Monday 28th June 2010 - Cracks!
« on: June 28, 2010, 05:47:07 am »
This week we look at cracks, formed when a sheet of lava cools and contracts.

The following image was posted by Aliko in the Interesting Terrain thread. The second image shows the area immediately below the first.
This area is just outside Proclus crater, between Mare Tranquillitatis and Mare Crisium, and shows part of the impact melt sheet formed when Proclus crater was created.


# ID: AMZ1002ix6
# Latitude: 16.3718°
# Longitude: 46.5211°
http://www.moonzoo.org/examine/AMZ1002ix6



Quote from: IreneAnt
Amazing image Aliko. I think you are looking at an impact melt sheet on the rim of a crater. The cracks, as Jules suggests, were likely formed when the melt sheet cooled.

Another good example of cracks, this time from the far side:


[NASA/GSFC/Arizona State University]

This image shows the impact melt sheet on the floor of Necho crater. Image width is just over 1 km and the cracks are 10 to 15 m wide.
More information and images of Necho can be found here: http://photojournal.jpl.nasa.gov/catalog/PIA12898
and a close-up of the Necho impact melt sheet will be found here: http://www.space.com/common/forums/viewtopic.php?f=6&t=753&start=140#p377730

Thomas J

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Re: Monday 28th June 2010 - Cracks!
« Reply #1 on: June 28, 2010, 11:22:29 am »
Thanks Geoff, this is an interesting read.

Thanks, too, for the links.

Thomas  :)

jules

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Re: Monday 28th June 2010 - Cracks!
« Reply #2 on: June 28, 2010, 01:23:44 pm »
Cracking IOTW Geoff! ;)

Geoff

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Re: Monday 28th June 2010 - Cracks!
« Reply #3 on: June 28, 2010, 01:26:28 pm »
 ;D

DJ_59

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Re: Monday 28th June 2010 - Cracks!
« Reply #4 on: June 29, 2010, 07:24:04 am »

That bottom image looks like something in a sci-fi flick.  It's mesmerizing.

Aliko

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Re: Monday 28th June 2010 - Cracks!
« Reply #5 on: June 29, 2010, 05:59:03 pm »
I found this cracks no my fist day at MZ  ;D