by kovil » Thu Apr 06, 2006 5:12 pm
Where I live here in Nevada, there is a similar looking salt that will migrate up to the surface after the winter moisture dries in the spring. The summer wind storms blow it away, and that is why our noses bleed at that time of year (unless you get used to it), all that alkalai in the air.
This area was once the Lohantan Sea, and when it left long ago, a several inch thick salt layer is under the soil several feet down, the ensueing years covered it over with silt etc, at the very bottom of the valleys that is. Anything on the higher hills was eroded off. When I backhoed the trenches for the utility lines at my place here, and dug the basement for the pressure tank for the water system so it wouldn't freeze in the winter time and I wouldn't have to heat it, the salt layers were 5' to 6' down and varied from 8" thick and unbreakable to nonexistant, and averaged 3-4" thick and quite hard. A sort of amalgum of a salty stuff and the natural soil. I figure it is the ancient seabed, in the pooling low spots where it finally finished evaporating, after some geological events caused the land to rise (when the Sierra Nevada mountains were formed) and the Sea to drain out, most likely down towards Baja California. I also wonder if the drainout was what caused the Grand Canyon to form. As the Colorado River might have needed some help in that one spot.
The salty white powder shows up every spring in a splochy way all over the lowest valley areas.
Where I live here in Nevada, there is a similar looking salt that will migrate up to the surface after the winter moisture dries in the spring. The summer wind storms blow it away, and that is why our noses bleed at that time of year (unless you get used to it), all that alkalai in the air.
This area was once the Lohantan Sea, and when it left long ago, a several inch thick salt layer is under the soil several feet down, the ensueing years covered it over with silt etc, at the very bottom of the valleys that is. Anything on the higher hills was eroded off. When I backhoed the trenches for the utility lines at my place here, and dug the basement for the pressure tank for the water system so it wouldn't freeze in the winter time and I wouldn't have to heat it, the salt layers were 5' to 6' down and varied from 8" thick and unbreakable to nonexistant, and averaged 3-4" thick and quite hard. A sort of amalgum of a salty stuff and the natural soil. I figure it is the ancient seabed, in the pooling low spots where it finally finished evaporating, after some geological events caused the land to rise (when the Sierra Nevada mountains were formed) and the Sea to drain out, most likely down towards Baja California. I also wonder if the drainout was what caused the Grand Canyon to form. As the Colorado River might have needed some help in that one spot.
The salty white powder shows up every spring in a splochy way all over the lowest valley areas.