It has been studied by geologists for clues to conditions on the plateau during this time interval and to test hypotheses for the initial incision of the Grand Canyon At its reference section near Indian Wells, Arizona, the Bidahochi Formation is divided into three informal members.

The lower member is 214 feet (65 m) thick and consists mostly of mudstone and fine sandstone with a basal conglomerate of limestone and siltstone pebbles.

[3] The formation is exposed over an area of over 16,000 square kilometers (6,200 sq mi) in the Black Mesa and San Juan Basins.

[4] The formation is interpreted as mostly alluvium, though eolian, lacustrine, and spring deposits are also present, in addition to lava flows and ash beds.

[10] This has made it of interest to geologists attempting to reconstruct conditions on the Colorado Plateau during the Neogene[11] and for theories of the formation of the Grand Canyon.

This in turn is an indication that the southern Colorado Plateau has been semiarid throughout most of the Neogene, even at times when the rest of western North America was relatively damp.

According to this hypothesis, the lake filled to the point where it overtopped its basin to the west, resulting in rapid incision and formation of the canyon.

[13] In 1954, Charles Repenning and James Irwin defined a reference section near Indian Wells, and divided the unit into informal lower, volcanic, and upper members.