What's the red stuff in this alluvial fan satellite image?

January 21, 2012 12:01 PM

What is the red stuff in this satellite image?

What is the red stuff at the base of the alluvial fan in this image of the Taklamakan/Taklimakan Desert? Is it a mineral? A phreatophyte? If so, which one(s)?

posted by Listener to Science & Nature (4 answers total)

Best answer: looking more closely at the google maps of the area, it looks like the imaging software is marking trees or other vegetation in red. here's a closeup of the reddest part of that source image.
posted by Mach5 at 12:27 PM on January 21, 2012

Best answer: The source is http://asterweb.jpl.nasa.gov/gallery-detail.asp?name=fan, which is an Aster image. Determining what it is probably depends a lot on the local geology but a note to them might help. There is a this. Select "Aster image" for the image mode and you'll see that band 2 is red and ties to vegetation, like Mach5 found.
posted by jwells at 12:37 PM on January 21, 2012 [1 favorite]

I suspect that the image is false infrared and the red color is vegetation as described by Mach5.
posted by humboldt32 at 12:54 PM on January 21, 2012

Here's a beginning primer on remote sensing, including why vegetation shows up as red on some satellite images.
posted by desjardins at 4:22 PM on January 21, 2012