I've seen bulldust do that
On the road between Quilpie and Thargomindah, we drove through a big patch of bulldust. It was a miracle that we didn't get stuck in it. The bulldust flowed like water. It's finer than talcum powder and has an orange color (like Mars). We rolled the windows up as quick as we could but it still got in the car anyway (a 1976 Toyota Corolla). My wife and I were covered with bulldust. It diffused through out the car and got in the suitcase, covering our clothes. For the next 3 months afterwards, whenever I opened the Toyota's trunk, a little bit of bulldust would come wafting out.
Gary