Dust
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by
wassock
moderator
Been having a close look at Giza. There are some very big fans formed there so I figured bigfan = lotsa dust = erosion = good place to look for some changes. I've got 2 ice free images 2 years apart that can be compared fairly easily - the are of similar image quality and the magnification is close on the same. Save for one tiny maybe thing not found any changes as yet. Solor longitude for the 2 are 282 and 2 86 so southern summer
So here's the question: There is clearly a lot of something forming fans here each year but if it comes off the surface it either all goes back to where it started from PDQ (Because you can't see any sign of it post spring by way of changes) or it accumulates over the late summer/autumn ready to be vented again in the spring. Assuming the dust in collection in the dips and channels we should be able to see signs of this build up in a late season image (assuming that there is a fare bit as suggested by the image below. Are there any Autumn (fall) images of Giza anywhere? Any of them show any difference to the summer ones?
If there is a lot of dust in the fans below it should be showing up some where on the icefree images and assuming it doesn't fall in exactly tyhe same place every year then it should be showing up duifferences in the terrain year on year - unless it magically springs back to a monolayer soon as the ice melts?
Posted
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by
Kitharode
moderator
Nice one wassock. Outstanding stuff, as usual.
Need some thinking time (also as usual) but first off, does the dust show up a lot in winter because of the high contrast between dust and ice? Which I guess leads to; Is there enough contrast in summer to see the dust?
Posted
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by
wassock
moderator
The strip is 4 km across so even if its a thin layer in the fan it has come from a much smaller area around the vents (probably), so there shoukd be some sign of it either before every thing freezes up or once the ice has melted
Posted