A former salt-sulphur deposit/mine located 4.5 km (2.8 miles) SSW# of Freeport. Discovered in 1904 by the Guffey Company. The dome was discovered by drilling in 1902 based on the seepage of H2S/gas. Native S was found in oil tested in 1904. The first S test was 1906. First production occurred in 1912 and ended in 1968 (operated 1912-1935 & 1967-1968). Owned & operated by Freeport Sulfur (sulfur) (1912-1935). Operator by Hooker Chemical (sulfur) (1912-1935) and by Dow Chemical Company (salt) (1912-1935). This locality is now a U.S. strategic petroleum reserve facility.

Mineralization is a salt dome deposit (Mineral occurrence model information: Model code: 255; USGS model code: 35a.7 (35ag); Deposit model name: Salt-dome sulfur), hosted in limestone and the Louann Salt. The ore body is 91.44 meters thick with a depth-to-bottom of 304.8 meters and a depth-to-top of of 213.36 meters. The depth to caprock is 680 feet, to the sulfur is 700 feet, and to the salt is 1,136 feet. The salt volume is 1.5 cubic miles to 10,000 feet of depth. The caprock is 800 acres in areal extent. Local rocks include Beaumont Formation, areas predominantly sand.

Local alteration is the biogenic alteration of anhydrock to limestone.
(Local) Biogenic Alteration Of Anhydrock To Limestone.

Local geologic structures include a Piercement Salt Dome.

Workings at the site include underground workings with an area of 121.41 HA. Mining was accomplished using the Frasch production of S from 27 wells in a 300 acres area. Salt was mined using the solution process. The mill capacity was 2,000 tons per day of S.

Production information is found in: Halbouty, Michel T. (1979).

Reserve-Resource data are found in: The Mines Handbook: 17 (Freeport Sulfur Company).

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List

ⓘ Anhydrite

ⓘ Halite

ⓘ Native Sulphur

3 valid minerals.

Rock Types Recorded

Note: data is currently VERY limited. Please bear with us while we work towards adding this information!

Select Rock List Type

Alphabetical List Tree Diagram

ⓘ Anhydrite-stone

ⓘ Limestone

Detailed Mineral List:

ⓘ Anhydrite

Formula: CaSO₄

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

ⓘ Halite

Formula: NaCl

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

ⓘ Native Sulphur

Formula: S₈

References:

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘ	Native Sulphur	1.CC.05	S₈
Group 3 - Halides
ⓘ	Halite	3.AA.20	NaCl
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘ	Anhydrite	7.AD.30	CaSO₄

List of minerals for each chemical element

O	Oxygen
O	ⓘ Anhydrite	CaSO₄
Na	Sodium
Na	ⓘ Halite	NaCl
S	Sulfur
S	ⓘ Anhydrite	CaSO₄
S	ⓘ Native Sulphur	S₈
Cl	Chlorine
Cl	ⓘ Halite	NaCl
Ca	Calcium
Ca	ⓘ Anhydrite	CaSO₄

Other Databases

Link to USGS MRDS:	10061155

Other Regions, Features and Areas containing this locality

North America PlateTectonic Plate

Gulf of Mexico BasinBasin
Northern Gulf of Mexico MarginPassive Margin
Sabine DomainDomain

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References

The Mines Handbook: 17 (Freeport Sulfur Company).

Haynes, W. (1942), The Stone that Burns. Van Nostrand, New York, 344 pp.

Hawkins, M. E. and C. J. Jirik (1966), Salt domes in Texas, Louisiana, Mississippi, Alabama, and offshore tidelands: a survey, U.S. Bureau of Mines Information Circular 8313.

Halbouty, Michel T. (1967) Salt Domes - Gulf Region, United States and Mexico. Gulf Publishing Company.p.140

(2005) Mineral Resources Data System (MRDS), US Geological Survey.

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