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Penokee Gap, Bad River, Ashland County, Wisconsin, USAi
Regional Level Types
Penokee GapGap
Bad RiverRiver
Ashland CountyCounty
WisconsinState
USACountry

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Latitude & Longitude (WGS84):
46° 17' 46'' North , 90° 42' 21'' West
Latitude & Longitude (decimal):
46.29623,-90.70601
GRN:
N31W46
Type:
Gap
Köppen climate type:
Dfb : Warm-summer humid continental climate
Mindat Locality ID:
212367
Long-form identifier:
mindat:1:2:212367:0
GUID (UUID V4):
0


Penokee Gap refers to a water gap through Penokee Ridge west of Mellen, Wisconsin. Outcrops are accessible along a railroad track that follows the Bad River through the gorge. Railroad cuts, outcrops and small exploration pits expose a steeply tilted section of rocks ranging from Archean gneisses to a Proterozoic metasedimentary sequence. The Proterozoic rocks are, from oldest to youngest, the Bad River Dolomite, the Palms Formation quartzite, the Ironwood Banded Iron Formation and the Tyler Formation slates. A few Keweenawan diabase dikes intrude the sequence.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


7 valid minerals.

Detailed Mineral List:

ⓘ 'Amphibole Supergroup'
Formula: AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ Andalusite
Formula: Al2(SiO4)O
ⓘ Andalusite var. Chiastolite
Formula: Al2(SiO4)O
ⓘ 'Biotite'
Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ Cordierite
Formula: Mg2Al4Si5O18
ⓘ Dolomite
Formula: CaMg(CO3)2
ⓘ 'K Feldspar'
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Muscovite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ Muscovite var. Sericite
Formula: KAl2(AlSi3O10)(OH)2
ⓘ 'Plagioclase'
Formula: (Na,Ca)[(Si,Al)AlSi2]O8
ⓘ Pyrite
Formula: FeS2
ⓘ Quartz
Formula: SiO2

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 2 - Sulphides and Sulfosalts
ⓘPyrite2.EB.05aFeS2
Group 4 - Oxides and Hydroxides
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘQuartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘDolomite5.AB.10CaMg(CO3)2
Group 9 - Silicates
ⓘAndalusite9.AF.10Al2(SiO4)O
ⓘvar. Chiastolite9.AF.10Al2(SiO4)O
ⓘCordierite9.CJ.10Mg2Al4Si5O18
ⓘMuscovite9.EC.15KAl2(AlSi3O10)(OH)2
ⓘvar. Sericite9.EC.15KAl2(AlSi3O10)(OH)2
Unclassified
ⓘ'Amphibole Supergroup'-AB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
ⓘ'Biotite'-K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
ⓘ'Plagioclase'-(Na,Ca)[(Si,Al)AlSi2]O8
ⓘ'K Feldspar'-

List of minerals for each chemical element

HHydrogen
Hⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Hⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Hⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Hⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CCarbon
Cⓘ DolomiteCaMg(CO3)2
OOxygen
Oⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Oⓘ AndalusiteAl2(SiO4)O
Oⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Oⓘ Andalusite var. ChiastoliteAl2(SiO4)O
Oⓘ CordieriteMg2Al4Si5O18
Oⓘ DolomiteCaMg(CO3)2
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Oⓘ QuartzSiO2
Oⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Oⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
FFluorine
Fⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Fⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
NaSodium
Naⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
MgMagnesium
Mgⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Mgⓘ CordieriteMg2Al4Si5O18
Mgⓘ DolomiteCaMg(CO3)2
AlAluminium
Alⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Alⓘ AndalusiteAl2(SiO4)O
Alⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Alⓘ Andalusite var. ChiastoliteAl2(SiO4)O
Alⓘ CordieriteMg2Al4Si5O18
Alⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Alⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Alⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
SiSilicon
Siⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Siⓘ AndalusiteAl2(SiO4)O
Siⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Siⓘ Andalusite var. ChiastoliteAl2(SiO4)O
Siⓘ CordieriteMg2Al4Si5O18
Siⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Siⓘ QuartzSiO2
Siⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
Siⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
SSulfur
Sⓘ PyriteFeS2
ClChlorine
Clⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
KPotassium
Kⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Kⓘ MuscoviteKAl2(AlSi3O10)(OH)2
Kⓘ Muscovite var. SericiteKAl2(AlSi3O10)(OH)2
CaCalcium
Caⓘ DolomiteCaMg(CO3)2
Caⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
TiTitanium
Tiⓘ Amphibole SupergroupAB2C5((Si,Al,Ti)8O22)(OH,F,Cl,O)2
Tiⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
FeIron
Feⓘ BiotiteK(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ PyriteFeS2

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate

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References

Van Hise, C. R. & R. Irving (1892) The Penokee iron-bearing series of northern Wisconsin and Michigan: U.S. Geological Survey Monograph 19, 634 p.
Klasner, J & G. LaBerge (1996) Field trip #5 Lake Namegakon and the Penokee Gap area, west Penokee Range in S. Nichols and L. Woodruff editors, Institute on Lake Superior, 42nd Annual Meeting, Part II Field Trip Guidebook: 83-108.
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