Peebee, that floating soil is silt. When we go though drought conditions here - it blows around all over and coats everything. Everything around here has a silt coating on it - even inside houses and buildings. A simple search link "perfect soil silt percentage"
https://www.google.com/?gws_rd=ssl#q...ilt+percentage 40% silt 40% sand 20% clay. Here are a couple pictures showing silt build up. I rubbed my hand on a table inside one of our barns - the other is on a deck.