The Kaibab Formation was first named by Darton (1910). The type section was moved by Nolan (1928) to Kaibab Gulch, about 8 miles southwest of the abandoned settlement of Paria, Utah about 6 miles north of the Arizona state line. At the type locality, it overlies the Toroweap Formation and is overlain by the Triassic Moenkopi Formation.

The Kaibab Formation is Permian (uppermost Leonardian to lower Guadalupian) in age. It commonly overlies the Arcturus Formation and is in turn overlain by the Plympton Formation in the area under study. The Grandeur member of the Park City Formation (McKelvey and others, 1959) is considered equivalent to the Kaibab Limestone (Wardlaw and others, 1979).

The Kaibab Formation is commonly a medium to very coarse-grained, massive, organic detrital, cliff-forming limestone which varies from light gray to yellowish gray or blue-gray in color. The limestones are locally dolomitic, particularly in the upper portion of the formation which contains abundant brown and light-gray chert nodules. It commonly forms rounded cliffs above the slope forming Arcturus Formation (Hose and Blake, 1976). In the Egan Range, silicified brachiopod faunas are prominent in the middle of the Kaibab (Brokaw and Heidrick, 1967).

In Lincoln County, the Kaibab commonly contains a lower cliff-forming member of light-gray limestone with up to 60 percent gray to dark-brown weathering irregular chert nodules. This is overlain by an upper member of thin-bedded limestone and dolomite with silty partings (Tschanz and Pampeyan, 1970).

In the Currie area the Kaibab Formation is about 200 feet of pale-gray, brown-gray weathering, fine-grained limestone with scattered gray chert nodules (Nelson, 1956). In the Spruce Mountain Quadrangle, Hope (1972) described the Kaibab as light-gray, medium to thick-bedded cherty limestone which overlies the Loray and underlies the Plympton Formations.

In the Egan Range near Ely, the Kaibab is a cliff-forming light to medium-gray fine to medium-grained massive limestone with abundant light-brown to gray nodular chert and silicified brachiopods (Brokaw and Heidrick, 1966; Brokaw, 1967). The upper portion of the formation has been eroded away along a regional unconformity at the top of the Kaibab.

In the Butte Mountains, several sections of the Kaibab, varying from about 77 feet to 550 feet, have been described by Bissell (1964). The Kaibab here is composed of various percentages of light yellow-gray, sandy micrite and interbedded coarsely crystalline encrinite, skeletal cherty and locally dolomitized limestone, and minor calcareous sandstone (Douglass, 1960; Bissell, 1964; Sides, 1966). Brown to black chert pods and nodules occur in the upper 50 feet of the unit (Sides, 1966).

In the Cherry Creek Range near Corral Canyon the Kaibab is composed of about 203 feet of pink-gray to light brown skeletal and micritic limestone, encrinal limestone, and two 4 feet thick chert-pebble conglomerate beds (Bissell, 1964). This is overlain by about 208 feet of red-gray to orange, micritic to coarse-grained limestone, and calcareous sandstone.

In the southern Pequop Mountains, the Kaibab Formation is light-gray, thick-bedded, coarsely bioclastic, crinoidal limestone. Light and dark gray chert nodules are abundant in the middle portion of the formation (Yochelson and Frazer, 1973). The Kaibab exposed in the Dolly Varden Mountains is lithologically similar with light pink-gray, thick-bedded to massive, fine-grained, encrinal limestone with the upper 45 feet being dolomitic (Snow, 1964; Bissell, 1964).

In the southern Schell Creek Range (T. 12 N., R. 65 E.) the Kaibab is thick-bedded to massive, gray to pink, micritic to sparitic encrinal limestone (Bissell, 1964). South of Patterson Pass (T. 7 N., R. 64 E.) the Kaibab is about 140 feet of thin to thick-bedded pink-gray and gray-brown, micritic limestone, cherty skeletal limestone, and thin sandy siltstone (Bissell, 1964). At Ferguson Mountain at the southern end of the Goshute Mountains, the Kaibab Formation is yellowish-gray, massive to locally medium-bedded, fine-grained limestone which is overlain by the Plympton Formation (Berge, 1960).

In the Medicine Range, the Kaibab is a prominent cliff-forming, medium gray dolomite with isolated beds of medium to dark gray, fetid limestone with bryozoans, crinoids, and productid brachiopods. Light gray chert nodules up to 6 inches long are present in the upper part of the formation (Collinson, 1968). The Kaibab is overlain by the Plympton in the Medicine Range. In the Maverick Springs Range, the Kaibab is thick-bedded and massive, slightly sandy, coarsely crystalline limestone and slightly dolomitic limestone (Bissell, 1964).

In the Egan Range near Ely about 150 to 400 feet of Kaibab is present (Brokaw and Heidrick, 1967; Brokaw, 1967), and 261 feet thick at Radar Ridge (Bissell, 1964). Hose and Blake (1976) estimated the thickness of the Kaibab in the Mount Grafton area of the southern Schell Creek Range to be from 50 to 200 feet, and Bissell (1964) reports about 138 feet in the Schell Creek Range in T. 12 N., R. 65 E and about 136 feet several miles south in T. 7 N., R. 64 E. The Kaibab Formation is about 255 feet thick in the southern Butte Mountains near Robbers Roost (Bissell, 1964) and varies from 77 to about 550 feet in the Butte Mountains (Bissell, 1964; Sides, 1966). It is about 200 feet thick in the Currie area (Nelson, 1956), 411 feet northeast of Corral Canyon in the Cherry Creek Range (Bissell, 1964), 400 feet thick in the Spruce Mountain Quadrangle (Hope, 1972), 150 to 300 feet in the southern Pequop Mountains (Bissell, 1964; Yochelson and Frazer, 1973), 420 feet at Ferguson Mountain (Berge, 1960), 280 to 320 feet in the Medicine Range (Bissell, 1964; Collinson, 1968), 82 feet in the Maverick Springs Range (Bissell, 1964), 130-165 feet just north of Ferguson Mountain (Bissell, 1964), and 214 feet thick in the Dolly Varden Mountains (Bissell, 1964).

The Kaibab is widely distributed in Clark County Nevada, northwestern Arizona and southwestern Utah, but occurs only sporadically in the eastern portion of the evaluation area. Small isolated outcrops of the Kaibab are found in the Twin Spring Hills, the Egan Range near Ely, Currie Hills, Cherry Creek Range, in the southeastern corner of Lincoln County, just north of the Kern Mountains, Red Hills, northern and southern Schell Creek and Maverick Springs and Medicine Ranges, Butte and Pequop Mountains, northern Goshute and Dolly Varden Mountains, southern Windermere Hills, Spruce Mountain Quadrangle, and near Granite Creek Reservoir in T. 43 N., R. 69 E.

The Kaibab represents shallow subtidal to supratidal environments along the outer shelf. Water depths were probably less than 100 meters (Roberts and others, 1965).