Double post there. S/R the first incomplete one Pete?

Anyway, pebbles are found on Mars?

http://news.sky.com/story/1097511/nasa-pebbles-find-supports-mars-life-theory

OK, so it's probable that it was flowing water that caused the bits of rock to be bundled along in the flow causing the bits of rock to become rounded in to a familar pebble shape BUT....

Mars is covered in dust, it could be that the bits of rock were rounded by "flowing" in a torrent of dust?

You don't need water to "round" the bits of rock, anything that causes them to move would produce the same effect?