The Dolores flows from the south, where it crosses the great salt dome of Paradox Valley, and the water is saline and has no fish.
The salt flow resulted in several kinds of structural traps mainly including salt ridge anticline, salt dome and salt edge syncline.
While many salt domes retain a cap of the youngest rock layers at the surface, in some cases the underlying salt extrudes all the way to the surface.
It is rare that salt dome surface itself yields a clearly defined reflection.
For instance, salt domes appear as negative anomalies because rock salt is of a lower density than all consolidated sediments.
