Tapeats Sandstone

Last updated
Tapeats Sandstone
Stratigraphic range: Middle Cambrian
508–507  Ma
Ꞓ
O
S
D
C
P
T
J
K
Pg
N
↓
[1] [2]
Grand Canyon-Mather point.jpg
Muav Limestone-(greenish, slope-forming) and Bright Angel Shale, resting on Tapeats and the Tonto Platform, inner canyon, Granite Gorge (the two units are easily seen below the red-stained Redwall Limestone) (220 m (720 ft) thick)
Type Geological formation
Unit of Tonto Group
Underlies Bright Angel Shale
Overlies Vishnu Basement Rocks, Unkar Group, Nankoweap Formation, Chuar Group, and Sixtymile Formation
Thickness70 m (230 ft)
Lithology
Primary sandstone and conglomerate
Otherconglomeratic sandstone
Location
Regionnorthern Arizona (Grand Canyon), central Arizona, southeast California, southern Nevada, and southeast Utah
Country United States of America
Type section
Named for Tapeats Creek [3]
Named byNoble (1914) [3]

Except where underlain by the Sixtymile Formation, the Tapeats Sandstone is the Cambrian geologic formation that is the basal geologic unit of the Tonto Group. Typically, it is also the basal geologic formation of the Phanerozoic strata exposed in the Grand Canyon, Arizona, and parts of northern Arizona, central Arizona, southeast California, southern Nevada, and southeast Utah. The Tapeats Sandstone is about 70 m (230 ft) thick, at its maximum. The lower and middle sandstone beds of the Tapeats Sandstone are well-cemented, resistant to erosion, and form brownish, vertical cliffs that rise above the underlying Precambrian strata outcropping within Granite Gorge (Inner Gorge). They form the edge of the Tonto Platform. The upper beds of the Tapeats Sandstone form the surface of the Tonto Platform. The overlying soft shales and siltstones of the Bright Angel Shale underlie drab-greenish slopes that rise from the Tonto Platform to cliffs formed by limestones of the Muav Limestone and dolomites of the Frenchman Mountain Dolostone. [2] [4] [5]

Contents

Nomenclature

In 1875, G. K. Gilbert [6] recognized that strata similar to those, named the Tonto Group, found in the Tonto Basin are exposed near the bottom of parts of the Grand Canyon. Based upon this similarity, he also assigned these strata to the Tonto Group. From youngest to oldest, Gilbert further subdivided the Tonto Group into three subunits, the Marbled limestone, the Tonto shale, and the Tonto sandstone. However, he did not specify a specific type locality for any of these stratigraphic units. [6]

In 1914, L F. Noble [3] officially redefined and renamed Gilbert's subdivisions of the Tonto Group. He renamed the Tonto sandstone as the Tapeats Sandstone and the Tonto shale as the Bright Angel Shale. He named the Tapeats Sandstone after Tapeats Creek in which this sandstone is exposed in the creek's bed. [3] Later in 1922, Noble renamed the Marbled limestone as the Muav Limestone. According to Noble's definition, the Muav Limestone consisted of an upper set of dolomite beds and a lower set of limestone beds. [7] The Muav Limestone is now applied only to Noble's lower set of limestone beds and the upper set of dolomite beds now constitutes the Frenchman Mountain Dolostone. [4] E. D. McKee and C. E. Resser [8] and subsequent researchers retained Noble's usage for this formation despite infrequent misgivings about their stratigraphic complexity. [9] [10]

Description

In the Grand Canyon, the Tapeats Sandstone is a medium- to coarse-grained, thin-bedded, cliff-forming and locally conglomeratic sandstone that weathers to a tan or reddish-brown. In its outcrops within the eastern part of the Grand Canyon, the Tapeats Sandstone is commonly divided into two layers. The lower portion of it consists of a lower layer of sandstone that outcrops as a cliff-forming cliff consisting of beds that are each typically less than 0.9 m (3.0 ft)thick. The beds exhibit sedimentary structures that include planar and trough cross-bedding and crudely developed horizontal bedding. Typically, the thickness of the bedding and cross-bedding decreases upwards in an outcrop. In paleotopographic lows along the Great Unconformity, the lower layer often has at its base a few beds composed of conglomeratic quartz and feldspar. The composition of these conglomeratic beds typically reflects the lithology of the underlying, local Precambrian basement rocks. Overlying the cliff-forming layer, is a thinner layer, known as the transitional beds, that consists of interbedded fine- to medium-grained sandstone and mudstone. The bedding in this upper layer is thinner than below and they exhibit largely trough and ripple cross stratification and horizontal lamination. The transitional beds grade upward into and interfinger with the overlying Bright Angel Shale. They form the surface of the Tonto Platform. In the western part of the Grand Canyon, a mudstone-rich layer often occurs sandwiched between these sandstone layers. [4] [11] [5]

The thickness of the Tapeats Sandstone exposed within the Grand Canyon varies from very thin to absent where it accumulated over prominent paleotopographic highs of the Great Unconformity to as thick as 90 m (300 ft) thick within paleotopographic lows. Where it is thickest, the upper 12 to 15 m (39 to 49 ft) belong to the transition beds underlying the Bright Angel Shale. [4] [5]

Lower Contact

Figure 1. A geologic cross section of the Grand Canyon. 2021 Revised USGS Geologic Stratigraphic Column of the Grand Canyon.jpg
Figure 1. A geologic cross section of the Grand Canyon.

Throughout the majority of its extent, the Tapeats Sandstone lies unconformably on the surface of underlying Precambrian rocks forming the Great Unconformity. Where the Sixtymile Formation underlies the Tapeats Sandstone, the Great Unconformity lies at the base of the Sixtymile Formation. This unconformity is either an angular unconformity truncating tilted strata of the Grand Canyon Supergroup or a nonconformity with the Vishnu Basement Rocks and other Precambrian metamorphic or plutonic rocks. Within the eastern Grand Canyon, the Tapeats Sandstone is separated from the underlying Precambrian rocks by the Cambrian Sixtymile Formation. [4] [11]

In the eastern Grand Canyon, the Tapeats Sandstone unconformably overlies a hilly and weathered paleosurface underlain by the Grand Canyon Group and Vishnu Basement Rocks. In one basin, the Cambrian Sixtymile Formation is preserved in a synclinal paleotopographic low in the Great Unconformity and separates the Tapeats Sandstone from it and the Grand Canyon Supergroup. The highest paleomonadnocks on this paleosurface are composed of Shinumo Quartzite and other erosion resistant strata of the Grand Canyon Group form paleocuestas of lesser and intermediate height. [2] [11]

In the western Grand Canyon, the Tapeats Sandstone unconformably overlies a similar hilly and weathered paleosurface underlain by the Vishnu Basement Rocks. This paleosurface is quite irregular and was before burial a rolling paleotopography of resistant crystalline basement hills rising above the surrounding lowlands. The relief on the Great Unconformity in the Grand Canyon represents ancient valleys and hills that influenced sedimentation patterns within the Tapeats Sandstone along with the local basement lithology. For example, there are numerous places where the Tapeats Sandstone thins across or terminates against ancient crystalline basement highs. Where the Tapeats Sandstone is absent, the Bright Angel Shale directly overlies the Great Unconformity. [3] [11] [13]

Throughout the Grand Canyon area, the Precambrian bedrock underlying the Tapeats Sandstone and Great Unconformity was extensively weathered and eroded during prolonged periods of subaerial exposure. Last studied by Sharp in 1940, [13] a highly altered ancient weathering horizon is locally preserved within the Precambrian rocks immediately underlying the Tapeats Sandstone. He concluded that extensive chemical weathering, which occurred prior to deposition of the Tapeats Sandstone, of exposed Precambrian rocks created a highly weathered bedrock, or regolith, as much as 15 m (49 ft) thick. Generally, this regolith is less than 30 m (98 ft) thick having been likely partially eroded and redeposited as Tapeats Sandstone. Where the Tapeats Sandstone rests on unaltered Precambrian basement, the regolith probably was removed by erosion either prior to or during the initial deposition of the Tapeats Sandstone. [11] [13]

Fossils

Despite the abundance of invertebrate burrows and trails (trace fossils) found in the Tapeats Sandstone, the body fossils of invertebrates, such as brachiopods and trilobites are absent, except where it interfingers with the overlying Bright Angel Shale. [9] [11] As summarized by Lassiter and others [14] 13 invertebrate taxa are reported as having been found in the Tapeats Sandstone. However, because of the gradational and interfingering natural of Tapeats Sandstone with the Bright Angel Shale and uncertainties in locations of collecting sites, at least some of these taxa are probably collected from the Bright Angel Shale instead. The arthropods include the trilobites, Olenellus and Spencella and the marine arthropods, Indianites and Walcottella. The brachiopods recorded from the Tapeats Sandstone include five species of the lingulate genus Lingula and two species of paterinate brachiopods, An unidentified species of obolellid brachiopod has been reported from the Tapeats Sandstone but remains unverified. [14]

The Tapeats Sandstone, especially its transitional beds, are often bioturbated and contains a wide variety of trace fossils. [9] These trace fossils commonly consist of ubiquitous vertical burrows and a large variety of horizontal tracks and trails. Many of the vertical burrows were most likely created by annelid worms and other soft bodied animals. The horizontal tracks and trails were likely created by gastropods and as well as arthropods (trilobites and crustaceans). [11] [15]

Depositional Environment

The Tapeats Sandstone consists of a mixture shallow marine, intertidal, and coastal plain deposits associated with an eastward advancing shoreline. The upper transitional beds represent sediment deposited on a deepening shallow-marine shelf. These shallow marine deposits overlie intertidal deposits reworked from braided fluvial and deltaic sediments deposited in front of an eastward advancing shoreline. Together, the Tapeats Sandstone, Bright Angel Shale, and Muav Limestone form a typical transgressive sedimentary sequence. [9] [10] [11]

In 2018, Karlstrom and others studied the age of detrital zircons from the Tapeats Sandstone in the Grand Canyon and southern Nevada using U-Pb dating. They interpreted the results of this study to indicate that the maximum depositional age of the Tapeats Sandstone to be from 505.4 ± 8 Ma to 501.4 ± 3.8 Ma and that it accumulated as an ancient shoreline gradually migrated eastward during the Cambrian Epoch 3. [1] [2]

Tonto Platform

The flat lying Tonto Platform has hiking trails that cross it from the South Rim to North Rim, Grand Canyon for instance. The extensive Tonto Trail lies on parts of the Tapeats Sandstone, and the platform on the south side of Granite Gorge. [4]

Examples of the Great Unconformity. The Tapeats approximately 200 ft thick.

See also

Related Research Articles

<span class="mw-page-title-main">Geology of the Grand Canyon area</span> Aspect of geology

The geology of the Grand Canyon area includes one of the most complete and studied sequences of rock on Earth. The nearly 40 major sedimentary rock layers exposed in the Grand Canyon and in the Grand Canyon National Park area range in age from about 200 million to nearly 2 billion years old. Most were deposited in warm, shallow seas and near ancient, long-gone sea shores in western North America. Both marine and terrestrial sediments are represented, including lithified sand dunes from an extinct desert. There are at least 14 known unconformities in the geologic record found in the Grand Canyon.

<span class="mw-page-title-main">Great Unconformity</span> Gap in geological strata

Of the many unconformities (gaps) observed in geological strata, the term Great Unconformity is frequently applied to either the unconformity observed by James Hutton in 1787 at Siccar Point in Scotland, or that observed by John Wesley Powell in the Grand Canyon in 1869. Both instances are exceptional examples of where the contacts between sedimentary strata and either sedimentary or crystalline strata of greatly different ages, origins, and structure represent periods of geologic time sufficiently long to raise great mountains and then erode them away.

<span class="mw-page-title-main">Tonto Group</span> Cambrian geologic unit in the Grand Canyon region, Arizona

The Tonto Group is a name for an assemblage of related sedimentary strata, collectively known by geologists as a Group, that comprises the basal sequence Paleozoic strata exposed in the sides of the Grand Canyon. As currently defined, the Tonto groups consists of the Sixtymile Formation, Tapeats Sandstone, Bright Angel Shale, Muav Limestone, and Frenchman Mountain Dolostone. Historically, it included only the Tapeats Sandstone, Bright Angel Shale, and Muav Limestone. Because these units are defined by lithology and three of them interfinger and intergrade laterally, they lack the simple layer cake geology as they are typically portrayed as having and geological mapping of them is complicated.

<span class="mw-page-title-main">Muav Limestone</span> Cambrian geologic formation found in the Southwestern United States

The Muav Limestone is a Cambrian geologic formation within the 5-member Tonto Group. It is a thin-bedded, gray, medium to fine-grained, mottled dolomite; coarse- to medium-grained, grayish-white, sandy dolomite and grayish-white, mottled, fine-grained limestone. It also contains beds of shale and intraformational conglomerate. The beds of the Muav Limestone are either structureless or exhibit horizontally laminations and cross-stratification. The Muav Limestone forms cliffs or small ledges that weather a dark gray or rusty-orange color. These cliffs or small ledges directly overlie the sloping surfaces of the Bright Angel Shale. The thickness of this formation decreases eastward from 76 m (249 ft) in the western Grand Canyon to 14 m (46 ft) in the eastern Grand Canyon. To the west in southern Nevada, its thickness increases to 250 m (820 ft) in the Frenchman Mountain region.

<span class="mw-page-title-main">Cardenas Basalt</span> Rock formation in the Grand Canyon, Arizona

The Cardenas Basalt, also known as either the Cardenas Lava or Cardenas Lavas, is a rock formation that outcrops over an area of about 310 km2 (120 mi2) in the eastern Grand Canyon, Coconino County, Arizona. The lower part of the Cardenas Basalt forms granular talus slopes. Its upper part forms nearly continuous low cliffs that are parallel to the general course of the Colorado River. The most complete, readily accessible, and easily studied exposure of the Cardenas Basalt lies in Basalt Canyon. This is also its type locality.

<span class="mw-page-title-main">Unkar Group</span> Sequence of geologic strata of Proterozoic age

The Unkar Group is a sequence of strata of Proterozoic age that are subdivided into five geologic formations and exposed within the Grand Canyon, Arizona, Southwestern United States. The Unkar Group is the basal formation of the Grand Canyon Supergroup. The Unkar is about 1,600 to 2,200 m thick and composed, in ascending order, of the Bass Formation, Hakatai Shale, Shinumo Quartzite, Dox Formation, and Cardenas Basalt. The Cardenas Basalt and Dox Formation are found mostly in the eastern region of Grand Canyon. The Shinumo Quartzite, Hakatai Shale, and Bass Formation are found in central Grand Canyon. The Unkar Group accumulated approximately between 1250 and 1104 Ma. In ascending order, the Unkar Group is overlain by the Nankoweap Formation, about 113 to 150 m thick; the Chuar Group, about 1,900 m (6,200 ft) thick; and the Sixtymile Formation, about 60 m (200 ft) thick. These are all of the units of the Grand Canyon Supergroup. The Unkar Group makes up approximately half of the thickness of the Grand Canyon Supergroup.

<span class="mw-page-title-main">Nankoweap Formation</span> Neoproterozoic geologic sequence of the Grand Canyon Supergroup

The Neoproterozoic Nankoweap Formation, is a thin sequence of distinctive red beds that consist of reddish brown and tan sandstones and subordinate siltstones and mudrocks that unconformably overlie basaltic lava flows of the Cardenas Basalt of the Unkar Group and underlie the sedimentary strata of the Galeros Formation of the Chuar Group. The Nankoweap Formation is slightly more than 100 m in thickness. It is informally subdivided into informal lower and upper members that are separated and enclosed by unconformities. Its lower (ferruginous) member is 0 to 15 m thick. The Grand Canyon Supergroup, of which the Nankoweap Formation is part, unconformably overlies deeply eroded granites, gneisses, pegmatites, and schists that comprise Vishnu Basement Rocks.

<span class="mw-page-title-main">Isis Temple</span> Landform in the Grand Canyon, Arizona

Isis Temple is a prominence in the Grand Canyon, Arizona, Southwestern United States. It is located below the North Rim and adjacent to the Granite Gorge along the Colorado River. The Trinity Creek and canyon flow due south at its west border; its north, and northeast border/flank is formed by Phantom Creek and canyon, a west tributary of Bright Angel Creek; the creeks intersect about 3 mi (4.8 km) southeast, and 1.0 mi (1.6 km) north of Granite Gorge. The Isis Temple prominence, is only about 202 ft (62 m) lower than Grand Canyon Village, the main public center on Grand Canyon’s South Rim.

<span class="mw-page-title-main">Grand Canyon Supergroup</span> Sequence of sedimentary strata

The Grand Canyon Supergroup is a Mesoproterozoic to a Neoproterozoic sequence of sedimentary strata, partially exposed in the eastern Grand Canyon of Arizona. This group comprises the Unkar Group, Nankoweap Formation, Chuar Group and the Sixtymile Formation, which overlie Vishnu Basement Rocks. Several notable landmarks of the Grand Canyon, such as the Isis Temple and Cheops Pyramid, and the Apollo Temple, are surface manifestations of the Grand Canyon Supergroup.

<span class="mw-page-title-main">Hakatai Shale</span> Mesoproterozoic rock formation

The Hakatai Shale is a Mesoproterozoic rock formation with important exposures in the Grand Canyon, Coconino County, Arizona. It consists of colorful strata that exhibit colors varying from purple to red to brilliant orange. These colors are the result of the oxidation of iron-bearing minerals in the Hakatai Shale. It consists of lower and middle members that consist of bright-red, slope-forming, highly fractured, argillaceous mudstones and shale and an upper member composed of purple and red, cliff-forming, medium-grained sandstone. Its thickness, which apparently increases eastwards, varies from 137 to 300 m. In general, the Hakatai Shale and associated strata of the Unkar Group rocks dip northeast (10–30°) toward normal faults that dip 60° or more toward the southwest. This can be seen at the Palisades fault in the eastern part of the main Unkar Group outcrop area. In addition, thick, prominent, and dark-colored basaltic sills and dikes cut across the purple to red to brilliant orange strata of the Hakatai Shale.

<span class="mw-page-title-main">Bass Formation</span> Lithostratigraphic unit found in Arizona, US

The Bass Formation, also known as the Bass Limestone, is a Mesoproterozoic rock formation that outcrops in the eastern Grand Canyon, Coconino County, Arizona. The Bass Formation erodes as either cliffs or stair-stepped cliffs. In the case of the stair-stepped topography, resistant dolomite layers form risers and argillite layers form steep treads. In general, the Bass Formation in the Grand Canyon region and associated strata of the Unkar Group-rocks dip northeast (10°–30°) toward normal faults that dip 60+° toward the southwest. This can be seen at the Palisades fault in the eastern part of the main Unkar Group outcrop area. In addition, thick, prominent, and dark-colored basaltic sills intrude across the Bass Formation.

<span class="mw-page-title-main">Shinumo Quartzite</span> Mesoproterozoic rock formation in the Grand Canyon, Arizona

The Shinumo Quartzite also known as the Shinumo Sandstone, is a Mesoproterozoic rock formation, which outcrops in the eastern Grand Canyon, Coconino County, Arizona,. It is the 3rd member of the 5-unit Unkar Group. The Shinumo Quartzite consists of a series of massive, cliff-forming sandstones and sedimentary quartzites. Its cliffs contrast sharply with the stair-stepped topography of typically brightly-colored strata of the underlying slope-forming Hakatai Shale. Overlying the Shinumo, dark green to black, fissile, slope-forming shales of the Dox Formation create a well-defined notch. It and other formations of the Unkar Group occur as isolated fault-bound remnants along the main stem of the Colorado River and its tributaries in Grand Canyon.

Typically, the Shinumo Quartzite and associated strata of the Unkar Group dip northeast (10°–30°) toward normal faults that dip 60+° toward the southwest. This can be seen at the Palisades fault in the eastern part of the main Unkar Group outcrop area.

<span class="mw-page-title-main">Dox Formation</span> Landform in the Grand Canyon, Arizona

The Dox Formation, also known as the Dox Sandstone, is a Mesoproterozoic rock formation that outcrops in the eastern Grand Canyon, Coconino County, Arizona. The Dox Formation comprises the bulk of the Unkar Group, the older subdivision of the Grand Canyon Supergroup. The Unkar Group is about 1,600 to 2,200 m thick and composed of, in ascending order, the Bass Formation, Hakatai Shale, Shinumo Quartzite, Dox Formation, and Cardenas Basalt. The Unkar Group is overlain in ascending order by the Nankoweap Formation, about 113 to 150 m thick; the Chuar Group, about 1,900 m (6,200 ft) thick; and the Sixtymile Formation, about 60 m (200 ft) thick. The entire Grand Canyon Supergroup overlies deeply eroded granites, gneisses, pegmatites, and schists that comprise Vishnu Basement Rocks.

<span class="mw-page-title-main">Vishnu Basement Rocks</span> Lithostratigraphic unit in the Grand Canyon, Arizona

The Vishnu Basement Rocks is the name recommended for all Early Proterozoic crystalline rocks exposed in the Grand Canyon region. They form the crystalline basement rocks that underlie the Bass Limestone of the Unkar Group of the Grand Canyon Supergroup and the Tapeats Sandstone of the Tonto Group. These basement rocks have also been called either the Vishnu Complex or Vishnu Metamorphic Complex. These Early Proterozoic crystalline rocks consist of metamorphic rocks that are collectively known as the Granite Gorge Metamorphic Suite; sections of the Vishnu Basement Rocks contain Early Paleoproterozoic granite, granitic pegmatite, aplite, and granodiorite that have intruded these metamorphic rocks, and also, intrusive Early Paleoproterozoic ultramafic rocks.

<span class="mw-page-title-main">Bright Angel Shale</span> Cambrian geologic formation found in the Southwestern United States

The Bright Angel Shale is one of five geological formations that comprise the Cambrian Tonto Group. It and the other formations of the Tonto Group outcrop in the Grand Canyon, Arizona, and parts of northern Arizona, central Arizona, southeast California, southern Nevada, and southeast Utah. The Bright Angel Shale consists of locally fossiliferous, green and red-brown, micaceous, fissile shale (mudstone) and siltstone with local, thicker beds of brown to tan sandstone and limestone. It ranges in thickness from 57 to 450 ft. Typically, its thin-bedded shales and sandstones are interbedded in cm-scale cycles. They also exhibit abundant sedimentary structures that include current, oscillation, and interference ripples. The Bright Angel Shale also gradually grades downward into the underlying Tapeats Sandstone. It also complexly interfingers with the overlying Muav Limestone. These characters make the upper and lower contacts of the Bright Angel Shale often difficult to define. Typically, its thin-bedded shales and sandstones erode into green and red-brown slopes that rise from the Tonto Platform up to cliffs formed by limestones of the overlying Muav Limestone and dolomites of the Frenchman Mountain Dolostone.

The Neoproterozoic Chuar Group consists of 1,600 m (5,200 ft) of exceptionally well-preserved, unmetamorphosed sedimentary strata that is composed of about 85% mudrock. The Group is the approximate upper half of the Grand Canyon Supergroup, overlain by the thin, in comparison, Sixtymile Formation, the top member of the multi-membered Grand Canyon Supergroup. The outcrop of the Chuar Group strata is limited to exposures along the western bank of the Colorado River in a 150 km2 (58 sq mi) area of the eastern Grand Canyon, Arizona. The strata of the Chuar Group have been subdivided into the Galeros Formation (lower) and the Kwagunt Formation (upper) using the base of the prominent, thick sandstone unit.

<span class="mw-page-title-main">Sixtymile Formation</span> Cambrian geologic formation found in Grand Canyon, Arizona

The Sixtymile Formation is a very thin accumulation of sandstone, siltstone, and breccia underlying the Tapeats Sandstone that is exposed in only four places in the Chuar Valley. These exposures occur atop Nankoweap Butte and within Awatubi and Sixtymile Canyons in the eastern Grand Canyon, Arizona. The maximum preserved thickness of the Sixtymile Formation is about 60 m (200 ft). The actual depositional thickness of the Sixtymile Formation is unknown owing to erosion prior to deposition of the Tapeats Sandstone.

<span class="mw-page-title-main">Temple Butte Formation</span> Landform in the Grand Canyon, Arizona

The Devonian Temple Butte Formation, also called Temple Butte Limestone, outcrops through most of the Grand Canyon of Arizona, USA; it also occurs in southeast Nevada. Within the eastern Grand Canyon, it consists of thin, discontinuous and relatively inconspicuous lenses that fill paleovalleys cut into the underlying Muav Limestone. Within these paleovalleys, it at most, is only about 100 feet (30 m) thick at its maximum. Within the central and western Grand Canyon, the exposures are continuous. However, they tend to merge with cliffs of the much thicker and overlying Redwall Limestone.

<span class="mw-page-title-main">Zoroaster Temple</span> Landform in Coconino County, Arizona

Zoroaster Temple is a 7,123-foot-elevation (2,171-meter) summit located in the Grand Canyon, in Coconino County of Arizona, USA. It is situated 5.5 miles (8.9 km) northeast of the Yavapai Point overlook on the canyon's South Rim, from which it can be seen towering over 4,600 feet above the Colorado River and Granite Gorge. Its nearest higher neighbor is Brahma Temple, less than one mile to the north-northeast. Zoroaster Temple is named for Zoroaster, an ancient Iranian prophet. This name was used by George Wharton James and Clarence Dutton. Dutton began the tradition of naming geographical features in the Grand Canyon after mythological deities. This geographical feature's name was officially adopted in 1906 by the U.S. Board on Geographic Names.

The Frenchman Mountain Dolostone is the uppermost and youngest of five Cambrian geologic formations that comprise the Tonto Group. It consists of beds of mottled white to gray dolomite often separated by thin seams of shale, especially in its lower part. In the Grand Canyon, this formation forms vertical cliffs that thicken westward between the top of the Muav Limestone and the base of either the Devonian Temple Butte Formation or Mississippian Redwall Limestone. Because of unidentified trace fossils and lack of datable body fossils, the Frenchman Mountain Dolostone exact age is uncertain. Within the Grand Canyon, its thickness varies between 61 and 137 m. West into the Lake Mead region, it thickens abbr=on and is 370 m (1,210 ft) thick at Frenchman Mountain near Las Vegas, Nevada.

References

  1. 1 2 Karlstrom, K., Hagadorn, J., Gehrels, G., Matthews, W., Schmitz, M., Madronich, L., Mulder, J., Pecha, M., Giesler, D. and Crossey, L., 2018. Cambrian Sauk transgression in the Grand Canyon region redefined by detrital zircons. Nature Geoscience, 11(6), pp.438-443.
  2. 1 2 3 4 Karlstrom, K.E., Mohr, M.T., Schmitz, M.D., Sundberg, F.A., Rowland, S.M., Blakey, R., Foster, J.R., Crossey, L.J., Dehler, C.M. and Hagadorn, J.W., 2020. Redefining the Tonto Group of Grand Canyon and recalibrating the Cambrian time scale. Geology, 48(5), pp. 425–430.
  3. 1 2 3 4 5 Noble, LF (1914) The Shinumo quadrangle, Grand Canyon district, Arizona. Bulletin no. 549, US Geological Survey, Reston, Virginia. 42 pp.
  4. 1 2 3 4 5 6 Connors, T.B., Tweet, J.S., and Santucci, V.L., 2020. Stratigraphy of Grand Canyon National Park. In: Santucci, V.L., Tweet, J.S., ed., pp. 54–74, Grand Canyon National Park: Centennial Paleontological Resource Inventory (Non-sensitive Version) . Natural Resource Report NPS/GRCA/NRR—2020/2103. National Park Service, Fort Collins, Colorado, 603 pp.
  5. 1 2 3 Beus, S.S., and Billingsley, G.H., 1989. Paleozoic strata of the Grand Canyon, Arizona, in Elston, D.P., Billingsley, G.H., and Young, R.A., eds. Geology of Grand Canyon, northern Arizona (with Colorado River guides): Lees Ferry to Pierce Ferry, Arizona. Field trips for the 28th international geological congress. Museum of Northern Arizona Press, Flagstaff, Arizona. pp. 122–127.
  6. 1 2 Gilbert, G.K., 1875. Report upon the geology of portions of Nevada, Utah, California, and Arizona, Chapter 6. In Wheeler, G.M., ed., pp. 17–187, Report on the Geographical and Geological Explorations and Surveys West of the One Hundredth Meridian, vol. 3. U.S. Geological and Geographical Survey, Publication of the Wheeler Survey, Washington, D.C., 681 pp.
  7. ↑ Noble, L.F., 1922. A section of the Paleozoic formations of the Grand Canyon at the Bass Trail. U.S. Geological Survey Bulletin. 131-B, pp. 23–73
  8. ↑ McKee, E.D., and Resser, C.E., 1945, Cambrian history of the Grand Canyon region.Carnegie Institution of Washington Publication 563, 168 pp.
  9. 1 2 3 4 Rose, E (2006) "Nonmarine aspects of the Cambrian Tonto Group of the Grand Canyon, USA, and broader implications." Palaeoworld . 15:223–241.
  10. 1 2 Rose, E (2011) Modification of the nomenclature and a revised deposition model for the Cambrian Tonto Group of the Grand Canyon, Arizona. in JS Hollingsworth, FA Sundberg, and JR Foster, eds., pp. 77–98, "Cambrian Stratigraphy and Paleontology of Northern Arizona and Southern Nevada": Museum of Northern Arizona Bulletin 67, 321 p.
  11. 1 2 3 4 5 6 7 8 Middleton, L.T. and Elliott, D.K., 2003. Tonto Group, in Beus, S. S., and Morales, M., eds. Grand Canyon geology Museum of Northern Arizona Press, Flagstaff, Arizona. pp. 90–106.
  12. ↑ Karlstrom, K., Crossey, L., Mathis, A., and Bowman, C., 2021. Telling time at Grand Canyon National Park: 2020 update. Natural Resource Report NPS/GRCA/NRR—2021/2246. National Park Service, Fort Collins, Colorado. 36 pp.
  13. 1 2 3 Sharp, R.P., 1940. Ep-Archean and Ep-Algonkian erosion surfaces, Grand Canyon, Arizona.Bulletin of the Geological Society of America, 51(8), pp.1235-1269.
  14. 1 2 Lassiter, S.L., Tweet, J.S., Sundberg, F.A., Foster, J.R., and Bergman, P.J., 2020. Chapter 5. Paleozoic Invertebrate Paleontology of Grand Canyon National Park. In: Santucci, V.L., Tweet, J.S., ed., pp. 109-236, Grand Canyon National Park: Centennial Paleontological Resource Inventory (Non-sensitive Version) . Natural Resource Report NPS/GRCA/NRR—2020/2103. National Park Service, Fort Collins, Colorado, 603 pp.
  15. ↑ Miller, A.E., Marchetti, L., Francischini, H., Lucas, S.G., 2020. Paleozoic invertebrate ichnology of Grand Canyon national Park. In: Santucci, V.L., Tweet, J.S., ed., pp. 277–331, Grand Canyon National Park: Centennial Paleontological Resource Inventory (Non-sensitive Version) . Natural Resource Report NPS/GRCA/NRR—2020/2103. National Park Service, Fort Collins, Colorado, 603 pp.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.