| Deposit ID | 10048940 |
|---|---|
| MRDS ID | MX00125 |
| Record type | Site |
| Current site name | El Boleo |
| Geographic coordinates: | -112.30069, 27.2836 (WGS84) |
|---|
Political divisions (FIPS codes)
Pima(county)
Arizona(state)
United States(country)
North America(continent)
Land(continent)
| Country | State |
|---|---|
| Mexico | Baja California Sur |
| Commodity | Importance |
|---|---|
| Copper | Primary |
| Zinc Critical | Primary |
| Silver | Secondary |
| Manganese Critical | Tertiary |
| Lead | Tertiary |
| Cobalt Critical | Tertiary |
| Materials | Type of material |
|---|---|
| Atacamite | Ore |
| Bornite | Ore |
| Chalcocite | Ore |
| Chalcopyrite | Ore |
| Chrysocolla | Ore |
| Covellite | Ore |
| Cuprite | Ore |
| Galena | Ore |
| Malachite | Ore |
| Melaconite | Ore |
| Pyrolusite | Ore |
| Calcite | Gangue |
| Chalcedony | Gangue |
| Gypsum | Gangue |
| Jasper | Gangue |
| Montmorillonite | Gangue |
| Result | AVERAGE GRADE OF ORE MINED 1886-1947: 4.8% CU |
|---|---|
| Result | RANGED FROM > 8% TO 3-3.5%. OTHER ANOMALOUS ELEMENTS: 0.05-6.0% ZN (AVG. 0.8%), 0.02-0.86% CO (AVG. 0.12%), MINOR AG. |
| Model code | 87 |
|---|---|
| USGS model code | 23 |
| Deposit model name | Basaltic Cu (BC name is Volcanic redbed Cu) |
| Mark3 model number | 118 |
| Host or associated | Host | ||||
|---|---|---|---|---|---|
| Rock type | Metamorphic Rock > Metasedimentary Rock > Meta-Argillite | ||||
| Rock unit name | Boleo Formation | ||||
| Rock description | Boleo Formation | ||||
| |||||
| Host or associated | Host |
|---|---|
| Rock type | Sedimentary Rock > Clastic Sedimentary Rock > Conglomerate |
| (1) | -112.30069, 27.2836 |
|---|
| Type of structure | Regional |
|---|---|
| Structure description | Reg.Struct: Underlying Miocene Volcanics Are Cut By Normal Faults With Displacements Of 50-100 M Into A Series Of E Tilted Blocks Upon Which Post-Miocene Sediments And Tuffs Were Deposited (With Initial Dips). Section Was Later (Pliocene To Recent) Cut By En-Echelon Normal Faults Striking N 10-45 W And Dipping 65-70 Sw And Ne. Major Faults Inclined Towards The Sw, With Maximum Vertical Displacement Of 250 M (Sta. Agueda Fault). Most Faults Show Less Than 80 M Of Displacement. |
| Development status | Past Producer |
|---|---|
| Commodity type | Metallic |
| Deposit size | Large |
| Significant | No |
| Discovery year | 1868 |
| District name | Santa Rosalia/Mulege |
|---|
| Type of workings | Surface/Underground |
|---|---|
| Area | 2840HA |
| Length | 588000M |
| Overall depth | 255M |
| Agency | Database name | Acronym | Record ID | Notes |
|---|---|---|---|---|
| USGS | Mineral Resources Data System | MRDS | MX00125 |
SALAS, G.P., 1975, CARTA Y PROVINCIAS METALOGENETICAS DE LA REPUBLICA MEXICANA: CONSEJO DE RECURSOS MINERALES PUBLICACION 21 E, P. 187.
WILSON, I.F., 1956, GEOLOGIA DEL DISTRITO CUPRIFERO DEL BOLEO, BAJA CALIFORNIA IN GEOLOGIA MINERA DEL NOROESTE DE MEXICO; DEPOSITOS DE COBRE DE CANANEA, SONORA Y DE COBRE Y MANGANESO DE EL BOLEO Y LUCIFER, BAJA CALIFORNIA: CONGRESO GEOLOGICO INTERNACIONAL, XX, EXCURSIONES A-1 Y C-4, P. 53-68.
COX, D.P., AND SINGER, D.A., 1986, MINERAL DEPOSIT MODELS: USGS BULLETIN 1693, 379 P.
WILSON, 1955; WILSON, 1956.
WILSON, 1955.
| Subject category | Comment text |
|---|---|
| Deposit | THIN, SUBHORIZONTAL TABULAR ORE BODIES AND MANTOS IN ARGILLACEOUS TUFF. FIVE MAIN HORIZONS, EACH UNDERLAIN BY TUFF CONGLOMERATE OR EQUIVALENT ARENACEOUS TUFF BED. ORE HORIZONS NUMBERED 0, 1, 2, 3, AND 4 FROM TOP TO BOTTOM. SULFIDE ZONE ORE: FINELY DISSEMINATED BLACK CHALCOCITE ASSOCIATED WITH CHALCOPYRITE, BORNITE, COVELLITE, NATIVE CU, AND MINOR PYRITE AND GALENA. WIDESPREAD BUT ILL-DEFINED OXIDE ZONE CONTAINS NODULES (BOLEOS) OF CHRYSOCOLLA, AZURITE, MALACHITE, ATACAMITE, MELACONITE, CUPRITE, CRYPTOMELANE, AND PYROLUSITE. GANGUE CONSISTS OF MONTMORILLONITE AND ALTERED VOLCANIC ROCKS CROSSCUT BY VEINLETS OF GYPSUM, CALCITE, CHALCEDONY, AND JASPER. ORE ZONES SEPARATED FROM FOOTWALL CONGLOMERATE (OR TUFF) BY THIN LAYER (10-50 CM) OF FINELY LAMINATED ARENACEOUS TUFF. AVERAGE THICKNESS OF ORE BODIES: 60-80 CM. |
| Type | Date | Name | Affiliation | Comment |
|---|---|---|---|---|
| Reporter | 01-JUL-1987 | Staude, John-Mark G. (Page, Norman J.) | U.S. Geological Survey | |
| Updater | 01-MAY-1988 | Leonard, Kenneth R. | U.S. Geological Survey |
Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.