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Choctaw Salt Dome, Plaquemine, Iberville Parish, Louisiana, USAi
Regional Level Types
Choctaw Salt DomeDome
PlaquemineCity
Iberville ParishParish
LouisianaState
USACountry

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PhotosMapsSearch
09934780017272012698620.jpg
Hilgardite

Choctaw Salt Dome, Plaquemine, Iberville Parish, Louisiana, USA
03761990017378125059228.jpg
Hilgardite-3Tc

Choctaw Salt Dome, Plaquemine, Iberville Parish, Louisiana, USA
09934780017272012698620.jpg
Hilgardite

Choctaw Salt Dome, Plaquemine, Iberville Parish, Louisiana, USA
03761990017378125059228.jpg
Hilgardite-3Tc

Choctaw Salt Dome, Plaquemine, Iberville Parish, Louisiana, USA
09934780017272012698620.jpg
Hilgardite

Choctaw Salt Dome, Plaquemine, Iberville Parish, Louisiana, USA
03761990017378125059228.jpg
Hilgardite-3Tc

Choctaw Salt Dome, Plaquemine, Iberville Parish, Louisiana, USA
Latitude & Longitude (WGS84):
30° 18' 57'' North , 91° 18' 29'' West
Latitude & Longitude (decimal):
30.31608,-91.30814
GeoHash:
G#: 9vrh6nz7y
GRN:
N21W56
Type:
Dome
Köppen climate type:
Cfa : Humid subtropical climate
Nearest Settlements:
PlacePopulationDistance
Addis4,589 (2017)5.9km
Plaquemine6,871 (2017)7.7km
Crescent959 (2011)7.9km
Brusly2,785 (2017)10.1km
Grosse Tete631 (2017)16.0km
Nearest Clubs:
Local clubs are the best way to get access to collecting localities
ClubLocationDistance
Baton Rouge Gem & Mineral SocietyBaton Rouge, Louisiana18km
Mindat Locality ID:
3770
Long-form identifier:
mindat:1:2:3770:2
GUID (UUID V4):
0
Other/historical names associated with this locality:
Bayou Choctaw Salt Dome


Besides being the type locality of Hilgardite, it is also the "first recorded locality" of its polytypes Hilgardite-3Tc and Hilgardite-4M.

A former salt (halite) occurrence/mine located in T9S, R12E, LM, and now a strategic petroleum reserve storage facility, located 7.2 km (4.47 mi) WNW of Plaquemine, on the N end of Bayou Choctaw (swamp), on private land. Owned and operated by the Union Texas Petroleum Company, Texas (1975).

The Bayou Choctaw salt diapir appears as a relatively slender, vertical feature, which gives the impression of having moved more or less straight upward. The layered sediments outside the dome are much more steeply inclined at depth than they are at shallower elevations. This style of deformation is consistent with continuing uplift of the salt — or progressive sedimentary downbuilding — during deposition of the surrounding sediments. Emplacement of the Bayou Choctaw salt dome clearly took place over a long period of time.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.


Mineral List


17 valid minerals. 1 (TL) - type locality of valid minerals.

Detailed Mineral List:

ⓘ Anhydrite
Formula: CaSO4
ⓘ Ankerite
Formula: Ca(Fe2+,Mg)(CO3)2
ⓘ Boracite
Formula: Mg3(B7O13)Cl
ⓘ Calcite
Formula: CaCO3
ⓘ Danburite
Formula: CaB2Si2O8
ⓘ Dolomite
Formula: CaMg(CO3)2
ⓘ Goethite
Formula: Fe3+O(OH)
ⓘ Gypsum
Formula: CaSO4 · 2H2O
ⓘ Halite
Formula: NaCl
ⓘ Hauerite
Formula: MnS2
ⓘ Hematite
Formula: Fe2O3
ⓘ Hilgardite (TL)
Formula: Ca2B5O9Cl · H2O
Type Locality:
ⓘ 'Hilgardite-3Tc'
Formula: Ca2B5O9Cl · H2O
ⓘ 'Hilgardite-4M'
Formula: Ca2B5O9Cl · H2O
ⓘ 'Limonite'
ⓘ Magnesite
Formula: MgCO3
ⓘ Marcasite
Formula: FeS2
ⓘ Native Sulphur
Formula: S8
ⓘ Pyrite
Formula: FeS2
ⓘ Quartz
Formula: SiO2

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘNative Sulphur1.CC.05S8
Group 2 - Sulphides and Sulfosalts
ⓘHauerite2.EB.05aMnS2
ⓘPyrite2.EB.05aFeS2
ⓘMarcasite2.EB.10aFeS2
Group 3 - Halides
ⓘHalite3.AA.20NaCl
Group 4 - Oxides and Hydroxides
ⓘGoethite4.00.Fe3+O(OH)
ⓘHematite4.CB.05Fe2O3
ⓘQuartz4.DA.05SiO2
Group 5 - Nitrates and Carbonates
ⓘCalcite5.AB.05CaCO3
ⓘMagnesite5.AB.05MgCO3
ⓘAnkerite5.AB.10Ca(Fe2+,Mg)(CO3)2
ⓘDolomite5.AB.10CaMg(CO3)2
Group 6 - Borates
ⓘHilgardite (TL)6.ED.05Ca2B5O9Cl · H2O
ⓘBoracite6.GA.05Mg3(B7O13)Cl
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘAnhydrite7.AD.30CaSO4
ⓘGypsum7.CD.40CaSO4 · 2H2O
Group 9 - Silicates
ⓘDanburite9.FA.65CaB2Si2O8
Unclassified
ⓘ'Limonite'-
ⓘ'Hilgardite-3Tc'-Ca2B5O9Cl · H2O
ⓘ'Hilgardite-4M'-Ca2B5O9Cl · H2O

List of minerals for each chemical element

HHydrogen
Hⓘ GoethiteFe3+O(OH)
Hⓘ GypsumCaSO4 · 2H2O
Hⓘ HilgarditeCa2B5O9Cl · H2O
Hⓘ Hilgardite-3TcCa2B5O9Cl · H2O
Hⓘ Hilgardite-4MCa2B5O9Cl · H2O
BBoron
Bⓘ BoraciteMg3(B7O13)Cl
Bⓘ DanburiteCaB2Si2O8
Bⓘ HilgarditeCa2B5O9Cl · H2O
Bⓘ Hilgardite-3TcCa2B5O9Cl · H2O
Bⓘ Hilgardite-4MCa2B5O9Cl · H2O
CCarbon
Cⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Cⓘ CalciteCaCO3
Cⓘ DolomiteCaMg(CO3)2
Cⓘ MagnesiteMgCO3
OOxygen
Oⓘ AnhydriteCaSO4
Oⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Oⓘ BoraciteMg3(B7O13)Cl
Oⓘ CalciteCaCO3
Oⓘ DanburiteCaB2Si2O8
Oⓘ DolomiteCaMg(CO3)2
Oⓘ GoethiteFe3+O(OH)
Oⓘ GypsumCaSO4 · 2H2O
Oⓘ HematiteFe2O3
Oⓘ HilgarditeCa2B5O9Cl · H2O
Oⓘ MagnesiteMgCO3
Oⓘ QuartzSiO2
Oⓘ Hilgardite-3TcCa2B5O9Cl · H2O
Oⓘ Hilgardite-4MCa2B5O9Cl · H2O
NaSodium
Naⓘ HaliteNaCl
MgMagnesium
Mgⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Mgⓘ BoraciteMg3(B7O13)Cl
Mgⓘ DolomiteCaMg(CO3)2
Mgⓘ MagnesiteMgCO3
SiSilicon
Siⓘ DanburiteCaB2Si2O8
Siⓘ QuartzSiO2
SSulfur
Sⓘ AnhydriteCaSO4
Sⓘ GypsumCaSO4 · 2H2O
Sⓘ HaueriteMnS2
Sⓘ MarcasiteFeS2
Sⓘ PyriteFeS2
Sⓘ Native SulphurS8
ClChlorine
Clⓘ BoraciteMg3(B7O13)Cl
Clⓘ HaliteNaCl
Clⓘ HilgarditeCa2B5O9Cl · H2O
Clⓘ Hilgardite-3TcCa2B5O9Cl · H2O
Clⓘ Hilgardite-4MCa2B5O9Cl · H2O
CaCalcium
Caⓘ AnhydriteCaSO4
Caⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Caⓘ CalciteCaCO3
Caⓘ DanburiteCaB2Si2O8
Caⓘ DolomiteCaMg(CO3)2
Caⓘ GypsumCaSO4 · 2H2O
Caⓘ HilgarditeCa2B5O9Cl · H2O
Caⓘ Hilgardite-3TcCa2B5O9Cl · H2O
Caⓘ Hilgardite-4MCa2B5O9Cl · H2O
MnManganese
Mnⓘ HaueriteMnS2
FeIron
Feⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Feⓘ GoethiteFe3+O(OH)
Feⓘ HematiteFe2O3
Feⓘ MarcasiteFeS2
Feⓘ PyriteFeS2

Other Databases

Link to USGS MRDS:10242574

Other Regions, Features and Areas containing this locality

North AmericaContinent
North America PlateTectonic Plate

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

www.osti.gov (n.d.) https://www.osti.gov/servlets/purl/1124260
www.geostockus.com (n.d.) http://www.geostockus.com/wp-content/uploads/Rautman_SMRI%202010.pdf
Hurlbut, Cornelius S., Taylor, and Ralph E. (1937) Hilgardite, a new mineral species, from Choctaw salt dome, Louisiana. American Mineralogist, 22 (10) 1052-1057
Taylor (1937) Bulletin of the American Association of Petroleum Geologists: 21: 1268.
American Mineralogist (1938): 23: 898.
Palache, Charles, Berman, Harry, Frondel, Clifford (1951) The System of Mineralogy (7th ed.) Vol. 2 - Halides, Nitrates, Borates, Carbonates, Sulfates, Phosphates, Arsenates, Tungstates, Molybdates, Ect. John Wiley and Sons, New York.pages 380, 383, 384
Rocks & Minerals (1970): 45(5): 299-303.
Jirik, Charles J. & Weaver, Louis K (1975), A Survey of Salt Deposits & Salt Caverns Their Relevance to the Strategic Petroleum Reserve, FEA/S-76/310 1975.
Ghose, Subrata, Wan, Che'ng (1979) Hilgardite, Ca2[B5O9]ClH2O: a piezoelectric zeolite-type pentaborate. American Mineralogist, 64 (1-2) 187-195
Ghose, Subrata (1985) A new nomenclature for the borate minerals in the hilgardite (Ca2B5O9Cl·H2O)-tyretskite (Ca2B5O9OH·H2O) group. American Mineralogist, 70 (5-6) 636-637
Rocks & Minerals (1994): 69(3): 156-162.
U.S. Bureau of Mines (1995), Minerals Availability System (MAS) file ID #0220470001.
(2005) Mineral Resources Data System (MRDS), US Geological Survey.
[1]Rautman, Christopher A., Karl M. Looff, and Kurt M. Looff (2009), A Three-Dimensional Geometric Model of the Bayou Choctaw Salt Dome, Southern Louisiana, Using 3-D Seismic Data, SAND2009-1037, Sandia National Laboratories, Albuquerque, New Mexico.
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