Unnamed Bentonite occurrence , Winslow, Winslow Mining District, Navajo Co., Arizona, USAi
|Regional Level Types|
|Unnamed Bentonite occurrence ||Occurrence|
|Winslow||- not defined -|
|Winslow Mining District||Mining District|
A bentonite occurrence located in sec. 11, T20N, R17E, G&SRM, 21.8 km (13.6 miles) NE of Winslow. The USGS MRDS database stated accuracy for this locality is 1,000 meters. NOTE: The MRDS file states that the center of the section was used for coordinates.
Mineralization is bentonite hosted in Late Triassic clay and mud of the Chinle Formation and clastic sedimentary rocks. Local rocks include rocks of the Chinle Formation.
Regions containing this locality
|North America Plate||Tectonic Plate|
|Colorado Plateau, USA||Plateau|
Select Mineral List TypeStandard Detailed Strunz Dana Chemical Elements
Commodity ListThis is a list of exploitable or exploited mineral commodities recorded at this locality.
Rock Types Recorded
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Detailed Mineral List:
| ⓘ 'Clays'|
Reference: USGS (2005), Mineral Resources Data System (MRDS): U.S. Geological Survey, Reston, Virginia, deposit ID #10056432.
List of minerals arranged by Strunz 10th Edition classification
|Unclassified Minerals, Rocks, etc.|
List of minerals arranged by Dana 8th Edition classification
|Unclassified Minerals, Mixtures, etc.|
List of minerals for each chemical element
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
0 - 0.0117 Ma
|Young alluvial fan deposits|
Age: Anthropocene (0 - 0.0117 Ma)
Description: Southwest of Little Colorado River Valley (sheet 1): Gray-brown silt, sand, gravel, pebbles, cobbles, and boulders; weakly consolidated by calcite, gypsum, and minor amounts of salt cement. Silt and sand is derived primarily from eroded outcrops of the Kaibab and Moenkopi Formations that also supply dissolved calcite, gypsum, and minor amounts of salt that precipitates as cement. Pebbles, cobbles, and boulders are subangular to rounded limestone, chert, and sandstone clasts locally derived from bedrock. Also includes small, subrounded to rounded pebbles and cobbles of basalt, andesite clasts, and pyroclastic fragments derived from San Francisco Volcanic Field west and southwest of quadrangle. Supports light to moderate growths of sagebrush, cactus, and grass. North and northeast of Little Colorado River Valley (sheet 2): Gray, light-brown, and light-red clay, silt, sand, pebbles, and cobbles of chert, limestone, and sandstone; derived from local Mesozoic sedimentary rocks and monchiquite, basanite, and decomposed tuff from local outcrops of the volcanic rocks of Hopi Buttes Volcanic Field. Commonly is overlapped by or intertongues with various Quaternary surficial deposits (Qs, Qps, Qf, Qd, Qes, Qv, Qg1, Qae). Clay, silt, and sand are derived primarily from local outcrops of the Chinle, Moenave, Kayenta, and Bidahochi Formations; also derived from Cretaceous rocks north and northeast of quadrangle that commonly supply cementing ingredients of clay, calcite, gypsum, and minor amounts of salt for all surficial alluvial deposits north and northeast of Little Colorado River. Subject to extensive sheet-wash erosion, wind erosion, flash-flood debris flows, and minor arroyo erosion. Thickness, 1 to 6 m (3 to 20 ft)
Reference: Billingsley, G.H., D. Block, and M. Hiza Redsteer. Geologic map of the Winslow 30’ × 60’ quadrangle, Coconino and Navajo Counties, northern Arizona. U.S. Geological Survey Scientific Investigations Map 3247. 
|Early Jurassic - Late Triassic|
174.1 - 237 Ma
|Mesozoic sedimentary rocks|
Age: Mesozoic (174.1 - 237 Ma)
Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529. 
|Norian - Carnian|
208.5 - 237 Ma
Age: Late Triassic (208.5 - 237 Ma)
Stratigraphic Name: Chinle Formation
Description: Colorful mudstone, such as in the Painted Desert, and less abundant lenses of sandstone and conglomerate, deposited by a large river system. This unit typically is eroded into badlands topography and contains clays that are prone to shrinking and swelling. (210-230 Ma)
Comments: Original map source: Arizona Geological Survey, DI-8 Geologic Map of Arizona, Digital Spatial data for the Geologic Map of Arizona, v. 3.0, edited by S.M. Richard and S.M. Kneale, 2002, 10 p., 2 DOS HD disks. Arc/INFO export file (.e00) format, scale 1:1,000,000.
Reference: Horton, J.D., C.A. San Juan, and D.B. Stoeser. The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. doi: 10.3133/ds1052. U.S. Geological Survey Data Series 1052.