Dakota Group (O; Peggy; Little Rock; Joseph; Jim; Wedge Claims; Gunnison; Vulcan; Rehl; Lucy; Tiger; Moh), Bald Mountain District, Lawrence Co., South Dakota, USA
|Latitude & Longitude (WGS84):||44° 20' 38'' North , 103° 50' 44'' West|
|Latitude & Longitude (decimal):||44.34389,-103.84556|
|Köppen climate type:||Dfb : Warm-summer humid continental climate|
REF:Deposit:: U.S. GEOLOGICAL SURVEY, U.S. BUREAU OF RECLAMATION, SOUTH DAKOTA GEOLOGICAL SURVEY, 1975 , MINERAL AND WATER RESOURCES OF SOUTH DAKOTA, SOUTH DAKOTA GEOLOGICAL SURVEY BULLETIN 16
Deposit:: US BUREAU OF MINES STAFF,REG V,1,1954,INFO CIRCULAR 7688,P.6
Deposit:: SHAPIRO & GRIES,1970,USGS HEAVY METALS PROGRAM CONTRACT #14-
Deposit:: US BUREAU OF MINES, 1954 , BLACK HILLS MINERAL ATLAS,
Commodities (Major) - Gold; (Minor) - Silver
Deposit Type: Replacement
Development Status: Past Producer
Host Rock Unit: Deadwood Formation
Commodity ListThis is a list of exploitable or exploited mineral commodities recorded at this locality.
2 valid minerals.
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
|Permian - Devonian|
252.17 - 419.2 Ma
|Paleozoic sedimentary rocks|
Age: Paleozoic (252.17 - 419.2 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. 
|Late Ordovician - Middle Cambrian|
443.8 - 511 Ma
|Whitewood Limestone, Winnipeg Formation, and Deadwood Formation|
Age: Paleozoic (443.8 - 511 Ma)
Stratigraphic Name: Whitewood Limestone; Winnipeg Formation; Deadwood Formation
Description: Whitewood Limestone (Ordovician)- Mottled, tan, gray to lavender, fine- to medium-crystalline, sparsely fossiliferous limestone and dolomite. Thickness up to 70 ft (21 m). Winnipeg Formation (Ordovician)- Grat and light-green, fissile shale, and tan, calcareous siltstone, sandy shale, and limestone lenses. Thickness up to 110 ft (34 m). Deadwood Formation (Ordovician to Cambrian)- Variegated, yellow to red, brown, gray, and green, glauconitic, conglomerate, sandstone, shale, dolomitic limestone, and dolomite. Thickness 4-400 ft (1-122 m).
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. 
|Early Ordovician - Late Cambrian|
470 - 501 Ma
Age: Paleozoic (470 - 501 Ma)
Stratigraphic Name: Deadwood Formation
Reference: Redden, J.A., E. DeWitt. Maps Showing Geology, Structure, and Geophysics of the Central Black Hills, South Dakota. U.S. Geological Survey Scientific Investigations Map 2777.