Sunday, 23 September 2007

Stars and stripes!

I hadn't intended to geo-blog today - or, at least, I thought I'd wait until Mark reached Bam but my roving eye got the better of me! Just some 50-100km to the north east of the road along which Mark is cycling this morning are some amazing patterns in the desert...To the west are these stripes . It is really difficult to work out what you are looking at here but stripes in deserts are not uncommon and often are associated with seif dunes which form parallel to the main wind direction or with yardangs which are linear ridges eroded by wind blown sand. I do wonder if what we are seeing here could be wind eroded ridges - covered in salt - a bit like the salt flats we've already looked at in Dasht e Kavir further north but modified by the effects of the wind. It's at moments like this that I wish we could persuade Mark to take a detour! To the east, however, the patterns are much easier to decipher...
...and are unmistakeably sand dunes which, according to my atlas, form the southern end of the second of Iran's great deserts, the Dasht e Lut. Zooming in more closely on one part of the dunes , I am seeing stars!

These dunes with three or more radiating legs are called star dunes and are most likely caused when winds blow from a number of directions, probably shifting with the seasons. On the ground they look like this ..
And finally.... a bit of trawling produced this image of the Dasht e Lut

The more I find out about Iran, the more I feel I need to get there.

P.S. re 'the stripes', I have just found this. I am relieved to read that I wasn't far out!

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