A gypsum occurrence located in the NE¼ sec. 18, T9N, R20E and/or secs. 27, 28, 33 & 34, T9N, R20E, G&SRM, approximately 25.2 km (15.7 miles) E of Cibecue and 8-10 miles W of US highway 60. The USGS MRDS database stated accuracy for this location is 1,000 meters.
Mineralization is massive beds of gypsum to 40 aggregate feet thick hosted in the Late Permian reddish siltstone of the Upper Supai Formation, upper block, upper Gypsum Zone. There are 2 gypsum zones of 16 & 18 feet thick, separated by 2 to 3 feet of reddish siltstone. Local rocks include Permian to Pennsylvanian sedimentary rocks and/or Oligocene to Paleocene[?] sedimentary rocks.
Regions containing this locality
|North America Plate||Tectonic Plate|
|Colorado Plateau, USA||Plateau|
|Fort Apache Indian Reservation, Arizona, USA||Reservation|
Select Mineral List TypeStandard Detailed Strunz Dana Chemical Elements
Commodity ListThis is a list of exploitable or exploited mineral commodities recorded at this locality.
1 valid mineral.
Rock Types Recorded
Select Rock List TypeAlphabetical List Tree Diagram
Detailed Mineral List:
| ⓘ Gypsum|
Formula: CaSO4 · 2H2O
Reference: Moore, Richard T. (1968), AZ Bur. Mines Bull. 177: 65; Elevatorski, E.A. (1978), Arizona Industrial Minerals, AZ Dept. of Min. Resources, Min Rpt. No. 2.
List of minerals arranged by Strunz 10th Edition classification
|Group 7 - Sulphates, Chromates, Molybdates and Tungstates|
|ⓘ||Gypsum||7.CD.40||CaSO4 · 2H2O|
List of minerals arranged by Dana 8th Edition classification
|Group 29 - HYDRATED ACID AND NORMAL SULFATES|
|ⓘ||Gypsum||22.214.171.124||CaSO4 · 2H2O|
List of minerals for each chemical element
|H||ⓘ Gypsum||CaSO4 · 2H2O|
|O||ⓘ Gypsum||CaSO4 · 2H2O|
|S||ⓘ Gypsum||CaSO4 · 2H2O|
|Ca||ⓘ Gypsum||CaSO4 · 2H2O|
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
|Rupelian - Danian|
28.1 - 66 Ma
|Oligocene to Paleocene[?] sedimentary rocks|
Age: Paleogene (28.1 - 66 Ma)
Stratigraphic Name: Chuska Sandstone
Description: "Rim gravels". Light colored, weakly to moderately consolidated conglomerate and sandstone deposited largely or entirely before mid-Tertiary volcanism and extensional faulting. Most sediment was deposited by early Cenozoic streams that flowed northeastward onto the Colorado Plateau from areas to the southwest that are now lower in elevation than the Plateau. Sediments of this map unit, other than the Chuska Sandstone in northeasternmost Arizona, are commonly referred to as "rim gravels" because they now rest on or near the Mogollon Rim, which is the southwestern edge of the Colorado Plateau. (30-65 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. 
251.902 - 298.9 Ma
|Paleozoic sedimentary rocks|
Age: Phanerozoic (251.902 - 298.9 Ma)
Lithology: Sedimentary rocks
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.