Grand Staircase

[1] In the 1870s, geologist Clarence Dutton first conceptualized this region as a huge stairway ascending out of the bottom of the Grand Canyon northward with the cliff edge of each layer forming giant steps.

The major canyons of the region did not start to form until about five to six million years ago when the Gulf of California opened up and thus lowered the river's base level (its lowest point).

Southern Utah has continued to reward researchers owing to its climatological "sweet spot" for exposing fossil remnants for observation and collection at the surface.

Further north, the wetter climates encourage growth of forests, which destroy fossils by the actions of roots and soil bacteria.

In southern Utah, there are enough strong and wet storms to cause episodic rapid erosion and the consequent exposure of fossil remains, but with insufficient annual average rainfall to support destructive, deep-rooted plant life.