The Kaibab Limestone is a resistant cliff-forming,

Permian The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleoz ...

geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

that crops out across the U.S. states of northern

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

, southern

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...

, east central

Nevada Nevada ( ; ) is a U.S. state, state in the Western United States, Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. N ...

and southeast

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

. It is also known as the Kaibab Formation in Arizona, Nevada, and Utah. The Kaibab Limestone forms the rim of the

Grand Canyon The Grand Canyon (, yuf-x-yav, Wi:kaʼi:la, , Southern Paiute language: Paxa’uipi, ) is a steep-sided canyon carved by the Colorado River in Arizona, United States. The Grand Canyon is long, up to wide and attains a depth of over a m ...

. In the Big Maria Mountains,

, the Kaibab Limestone is highly metamorphosed and known as the Kaibab Marble.

Nomenclature

The Kaibab Limestone was named by Darton in 1910 for the Kaibab Plateau, which is on the north side of

Coconino County, Arizona Coconino County is a County (United States), county in the north-central part of the U.S. state of Arizona. Its population was 145,101 at the 2020 United States census, 2020 census. The county seat is Flagstaff, Arizona, Flagstaff. The count ...

. In his definition of the Kaibab Limestone formation, no type locality was designated. He also designated the Kaibab Limestone as the upper formation of the Aubrey Group, a now-abandoned stratigraphic unit. In 1921, Bassler and Reeside revised Darton's work and defined the Harrisburg Member of the Kaibab Limestone.Bassler, H., and J. B. Reeside, Jr., 1921, ''Oil prospects in Washington County, Utah, Chapter C.'' in D. White and M. R. Campbell, eds., pp. C87–C107, Contributions to economic geology (short papers and preliminary reports), 1921, Part II. Mineral fuels. Bulletin no. 726. U.S. Geological Survey, Reston, Virginia. In his 1938 monograph on the

Toroweap Formation The Middle Permian Toroweap Formation is a thin, darker geologic unit, between the brighter colored units of the Kaibab Limestone above, and Coconino Sandstone below. It is a prominent unit in Grand Canyon, Arizona, USA, found through sections ...

and Kaibab Limestone of northern Arizona,McKee, E. D., 1938, ''The environment and history of the Toroweap Formation and Kaibab formations of northern Arizona and southern Utah.'' Publication, no. 492. Carnegie Institution of Washington, Washington, DC. 268 pp. McKee split Darton's original ''Kaibab Limestone'' into the currently recognized ''Kaibab Limestone'' and ''Toroweap Formation.'' He also revised Kaibab Limestone's lower contact and divided it into informal (descending) alpha, beta and gamma members. Later in the 1970s, its upper contact was revised and its areal extent were defined. Also, unsuccessful attempts were made to raise the formation to group rank and divide it into several formations. In 1982,

Warren Hamilton Warren Hamilton is an American politician and retired military officer serving as a member of the Oklahoma Senate from the 7th district. Elected in November 2020, he assumed office on January 5, 2021. Early life and education Hamilton was rai ...

renamed it as the Kaibab Marble and determined its areal extent for California.Hamilton, W. H., 1982, ''Structural evolution of the Big Maria Mountains, northeastern Riverside County, southeastern California.'' in E. G. Frost and D. L. Martin, eds., pp. 1–27, Mesozoic-Cenozoic tectonic evolution of the Colorado River region, California, Arizona, and Nevada. Cordilleran Publishers, San Diego, California, United States. 608 pp. In 1991, Sorauf and Billingsley subdivided the Kaibab Limestone into (ascending) Fossil Mountain Member (new) and Harrisburg Member.Sorauf, J. E. and G. H. Billingsley, 1991, ''Members of the Toroweap and Kaibab Formations, Lower Permian, northern Arizona and southwestern Utah.'' The Mountain Geologist, 28(1):9–24. They designated the strata comprising McKee's alpha (or upper) member as the Harrisburg Member and the strata comprising McKee's beta (or middle) member as the Fossil Mountain Member. The Fossil Mountain Member was named for Fossil Mountain along the south rim near the Bass Trail. McKee's gamma member is considered to be part of the Fossil Mountain Member. Later research has further redefined the regional extent of the Kaibab Limestone.

Description

The Kaibab Limestone is an assemblage of

sedimentary Sedimentary rocks are types of rock (geology), rock that are formed by the accumulation or deposition of mineral or organic matter, organic particles at Earth#Surface, Earth's surface, followed by cementation (geology), cementation. Sedimentati ...

rock types. It consists of a complexity of inter fingering and inter bedded

carbonate A carbonate is a salt of carbonic acid (H2CO3), characterized by the presence of the carbonate ion, a polyatomic ion with the formula . The word ''carbonate'' may also refer to a carbonate ester, an organic compound containing the carbonate g ...

and

siliciclastic Siliciclastic (or ''siliclastic'') rocks are clastic noncarbonate sedimentary rocks that are composed primarily of silicate minerals, such as quartz or clay minerals. Siliciclasic rock types include mudrock, sandstone Sandstone is a clastic ...

sedimentary rocks. In addition, intense post-depositional (

diagenetic Diagenesis () is the process that describes physical and chemical changes in sediments first caused by water-rock interactions, microbial activity, and compaction after their deposition. Increased pressure and temperature only start to play a ...

) changes have created more composition variation by the alteration of

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

dolomite Dolomite may refer to: *Dolomite (mineral), a carbonate mineral *Dolomite (rock), also known as dolostone, a sedimentary carbonate rock *Dolomite, Alabama, United States, an unincorporated community *Dolomite, California, United States, an unincor ...

and the silicification of limestone to form

chert Chert () is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a prec ...

. In the western Grand Canyon region, the Fossil Mountain Member consists of fossiliferous and cherty limestone with an abundant and diverse normal-

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

fauna Fauna is all of the animal life present in a particular region or time. The corresponding term for plants is ''flora'', and for fungi, it is '' funga''. Flora, fauna, funga and other forms of life are collectively referred to as '' biota''. Zoo ...

. Further east in the Coconino Plateau region, the

lithology The lithology of a rock unit is a description of its physical characteristics visible at outcrop, in hand or core samples, or with low magnification microscopy. Physical characteristics include colour, texture, grain size, and composition. Lit ...

mineralogy Mineralogy is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts. Specific studies within mineralogy include the proces ...

, and fauna of the Fossil Mountain Member changes drastically where it grades laterally into

sand Sand is a granular material composed of finely divided mineral particles. Sand has various compositions but is defined by its grain size. Sand grains are smaller than gravel and coarser than silt. Sand can also refer to a textural class of s ...

y dolomite and dolomite that contains a restricted-marine fossil fauna and subordinate amounts of

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

. The Harrisburg Member, which forms the uppermost cliffs and receding ledges along both north and south rims of the Grand Canyon, consists of an assemblage of

gypsum Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywall. ...

, dolomite, sandstone, redbeds, chert, and minor limestone.

Contacts

Within the Grand Canyon region, the Kaibab Limestone overlies gypsum and contorted sandstones of the Toroweap Formation. Originally, geologists interpreted the lower contact of the Kaibab Limestone to be an

unconformity An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval o ...

based on the presence of local intraformational

breccia Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix. The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of di ...

s and erosional surfaces. However, additional research has concluded that these local intraformational breccias and erosional surfaces are the result of collapse following the dissolution of

evaporite deposits An evaporite () is a water-soluble sedimentary mineral deposit that results from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporite deposits: marine, which can also be described as oce ...

within the upper part of the Toroweap Formation. As a result, this contact is inferred to be conformable or only locally a disconformity. South and east of the Grand Canyon, the evaporites and contorted sandstones ( sabkha deposits) of Toroweap Formation interfinger with and are replaced by cross-bedded sandstones of the Coconino Sandstone. As a result, the Kaibab Limestone directly overlies the Coconino Sandstone in the

Mogollon Rim The Mogollon Rim ( or or ) is a topographical and geological feature cutting across the northern half of the U.S. state of Arizona. It extends approximately , starting in northern Yavapai County and running eastward, ending near the border ...

region. The Kaibab Limestone directly overlies the

White Rim Sandstone The White Rim Sandstone is a sandstone geologic formation located in southeastern Utah. It is the last member of the Permian Cutler Group, and overlies the major Organ Rock Formation and Cedar Mesa Sandstone; and again overlies thinner units of ...

in northeastern Arizona and southeastern Utah. The upper contact of the Kaibab Limestone (Harrisburg Member) with the overlying Moenkopi Formation is an erosional unconformity and disconformity. Within northwestern Arizona, southeastern Nevada, and southwestern Utah this contact is an erosional unconformity that in part consists of paleovalleys, as much as several hundred feet deep, and paleokarst that were eroded into the underlying Kaibab Limestone before the deposition of the

Moenkopi Formation The Moenkopi Formation is a geological formation that is spread across the U.S. states of New Mexico, northern Arizona, Nevada, southeastern California, eastern Utah and western Colorado. This unit is considered to be a group in Arizona. Part ...

. These paleovalleys are often filled with conglomerates and

s that are known as the Rock Canyon conglomerate. Within the

Marble Canyon Marble Canyon is the section of the Colorado River canyon in northern Arizona from Lee's Ferry to the confluence with the Little Colorado River, which marks the beginning of the Grand Canyon. Lee's Ferry is a common launching point for rive ...

and eastern Grand Canyon regions and south into

Verde Valley The Verde Valley ( yuf-x-yav, Matkʼamvaha; es, Valle Verde) is a valley in central Arizona in the United States. The Verde River runs through it. The Verde River is one of Arizona's last free-flowing river systems. It provides crucial habitat ...

, upper contact of the Kaibab Limestone with the Moenkopi Formation is an erosional disconformity. This disconformity exhibits little relief and is identified by marked differences in color, topography, and rock types between tan, ledge-forming, calcareous sandstones and of the Kaibab Limestone and red, slope-forming siltstones of the Moenkopi formation. The unconformity and disconformity are inferred to represent most of Permian time (including the Leonardian) and part of Early Triassic time. Although the Moenkopi Formation overlies the Kaibab Limestone, its redbeds have been removed almost entirely by erosion because they are less resistant to erosion than the strata of the Kaibab Formation. As a result, the Kaibab Limestone forms the surface of many of the vast

plateau In geology and physical geography, a plateau (; ; ), also called a high plain or a tableland, is an area of a highland consisting of flat terrain that is raised sharply above the surrounding area on at least one side. Often one or more sides ha ...

s that border the Grand Canyon. Within these plateaus, the uppermost beds of the Kaibab Limestone have also been largely removed by erosion.

Fossils

The Kaibab Limestone contains the abundant fossils of Permian

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

s and

vertebrate Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...

s. The invertebrate fossils found within the Kaibab Limestone include brachiopods,

conodont Conodonts (Greek ''kōnos'', "cone", + ''odont'', "tooth") are an extinct group of agnathan (jawless) vertebrates resembling eels, classified in the class Conodonta. For many years, they were known only from their tooth-like oral elements, which ...

coral Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and sec ...

s, crinoids, echinoid spines,

mollusks Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...

hexactinellid Hexactinellid sponges are sponges with a skeleton made of four- and/or six-pointed siliceous spicules, often referred to as glass sponges. They are usually classified along with other sponges in the phylum Porifera, but some researchers consi ...

and other

sponges Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through ...

trilobite Trilobites (; meaning "three lobes") are extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the At ...

s, and burrows of callanassid

shrimp Shrimp are crustaceans (a form of shellfish) with elongated bodies and a primarily swimming mode of locomotion – most commonly Caridea and Dendrobranchiata of the decapod order, although some crustaceans outside of this order are refer ...

. The fossil

cephalopod A cephalopod is any member of the molluscan class Cephalopoda (Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head ...

s found in the Kaibab Limestone include giant football-sized nautiloids. Fossil shark teeth, which represent a diverse assemblage of chondrichthyans, occur within the Kaibab Limestone of Arizona.Hodnett, J.-P., D. K. Elliott, T. J. Olson, and J. H. Wittke, 2012, ''Ctenacanthiform sharks from the Permian Kaibab Formation, northern Arizona.'' Historical Biology. 24:1–15.Hodnett, J.-P., D. K. Elliott, and T. J. Olson, 2013, ''A new basal hybodont (Chondrichthyes, Hybodontiformes) from the Middle Permian (Roadian) Kaibab Formation of northern Arizona.'' In, S. G. Lucas, W. A. DiMichele, J. A. Barrick, J. W. Schneider, and J. S. Spielman, eds., pp. 103–08, The Carboniferous-Permian Transition. Bulletin no. 60. New Mexico Museum of Natural History and Science, Socorro, New Mexico.

Depositional environments

The complex intercalation of carbonate and clastic sediments within the Kaibab Limestone reflects the deposition of sediments within a gently sloping continental margin during a period of frequent, high-frequency sea level changes. Relatively minor changes in sea level caused major lateral shifts in the position of supratidal, subtidal, and shallow-marine environments during the deposition of the Kaibab Limestone. The shifting sea levels and associated depositional environments created a complex interlayering of different types of carbonate and clastic sediments in the strata that comprise the Kaibab Limestone. The gently sloping continental margin on which the Kaibab Limestone accumulated, extended seaward from northern Arizona to southern Nevada, at times exceeding 200 miles (125 km) in width. It is most likely that the high-frequency changes in sea level were caused by glacial sea level oscillations during this time period.

Age

Early paleontological studies of the Kaibab Limestone firmly established its age on the basis of the abundant fossils that it and the underlying Toroweap Formation contain. On the basis of its brachiopod and siliceous sponge faunas, it was initially concluded that it is Leonardian (approximately Kungurian / latest Early Permian) in age.Griffen, L. R., 1966. ''Actinocoelia maendria Finks, from the Kaibab Limestone of Northern Arizona.'' Brigham Young University Geology Studies. 13:105–08. Later research concerning

s and associated megafossils obtained from western outcrops of the Fossil Mountain Member indicates that its age extends into the Roadian (latest Early Permian and earliest Middle Permian) age.Thompson, K. L., 1995., ''Paleoecology and Biostratigraphy of the Fossil Mountain Member, Kaibab Formation, in Northwestern Arizona.'' Unpublished M.S. thesis, Northern Arizona University, 160 pp.

Geographic distribution

Geologic Province: *

Basin and Range province The Basin and Range Province is a vast physiographic region covering much of the inland Western United States and northwestern Mexico. It is defined by unique basin and range topography, characterized by abrupt changes in elevation, alternating ...

* *

Black Mesa Basin Black Mesa (also called Big Mountain) is an upland mountainous mesa of Arizona, north-trending in Navajo County, west and southeast-trending in Apache County. In Navajo it is called ('Black Mountain') and during Mexican rule of Arizona it was c ...

* *

Great Basin The Great Basin is the largest area of contiguous endorheic basin, endorheic watersheds, those with no outlets, in North America. It spans nearly all of Nevada, much of Utah, and portions of California, Idaho, Oregon, Wyoming, and Baja California ...

province* *

Paradox Basin The Paradox Basin is an asymmetric foreland basin located mostly in southeast Utah and southwest Colorado, but extending into northeast Arizona and northwest New Mexico. The basin is a large elongate northwest to southeast oriented depression for ...

* *

Plateau Sedimentary Province The Colorado Plateau, also known as the Colorado Plateau Province, is a physiographic and desert region of the Intermontane Plateaus, roughly centered on the Four Corners region of the southwestern United States. This province covers an area ...

* * Salton Basin* Parklands (incomplete list): * Capitol Reef National Park – See

Geology of the Capitol Reef area The exposed geology of the Capitol Reef area presents a record of mostly Mesozoic-aged sedimentation in an area of North America in and around Capitol Reef National Park, on the Colorado Plateau in southeastern Utah. Nearly 10,000 feet (3, ...

– See

Geology of the Grand Canyon area The geology of the Grand Canyon area includes one of the most complete and studied sequences of rock (geology), rock on Earth. The nearly 40 major sedimentary rock layers exposed in the Grand Canyon and in the Grand Canyon National Park area rang ...

* Zion National Park – See Geology of the Zion and Kolob canyons area * Grand Staircase–Escalante National Monument Other: *

Blue Diamond Mine The Blue Diamond Mine and mill is a gypsum production facility at Blue Diamond Hill in Clark County, Nevada. The mine was initially owned by a Los Angeles company known as Blue Diamond, which began mining the land in 1925. An on-site processing pla ...

on Blue Diamond Hill in Clark County, Nevada

References

Popular references

* Blakey, R., and W. Ranney, 2008, ''Ancient Landscapes of the Colorado Plateau.'' Grand Canyon Association, Grand Canyon Village, Arizona. 176 pp. * Chronic, H., 1983, ''Roadside Geology of Arizona.'' 23rd printing. Mountain Press Publishing Company, Missoula Montana. 322 pp. * Lucchitta, I., 2001, ''Hiking Arizona's Geology.'' Mountaineers's Books, Seattle, Washington. 269 pp.

External links

* Abbot, W, 2001
''Revisiting the Grand Canyon – Through the Eyes of Seismic Sequence Stratigraphy.''Search and Discovery Article # 40018
America Association of Petroleum Geologists, Tulsa, Oklahoma. * Anonymous, nda

* Anonymous, ndb

National Park Service, Canyon Village, Arizona. * Mathis, A., and C. Bowman, 2007
''The Grand Age of Rocks: The Numeric Ages for Rocks Exposed within Grand Canyon''Grand Canyon National Park, Arizona
National Park Service, Grand Canyon National Park, Arizona. * Shur, C., and D. Shur, 2008

{{Chronostratigraphy of Nevada Limestone formations of the United States Natural history of the Grand Canyon Geologic formations of Arizona Geologic formations of California Geologic formations of Nevada Geologic formations of Utah Permian Arizona Permian California Permian geology of Nevada Permian geology of Utah Cisuralian Series of North America