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Saddle

Prospect in Alaska, United States with commodity Gold
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Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Alteration
  8. Mineral occurrence model information
  9. Nearby scientific data
  10. Economic information about the deposit and operations
  11. Mining district
  12. Links to other databases
  13. Bibliographic references
  14. General comments
  15. Reporter information

Geologic information

Identification information

Deposit ID 10308323
Record type Site
Current site name Saddle

Geographic coordinates

Geographic coordinates: -163.71425, 64.57532 (WGS84)
Relative position This prospect is 1.3 miles northeast of Bluff, 0.6 miles north of Norton Sound, and at 360 feet elevation on the saddle between Daniels Creek (SO006) and Swede Creek (SO005).

Site location context

Political divisions (FIPS codes)

Nome(Census area)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Solomon C-4(quadrangle 1:63,360 scale)

Solomon NE(quadrangle 1:100,000 scale)

Solomon C(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Nome(hydrologic unit)

Norton Sound(hydrologic accounting unit)

Northwest(hydrologic subregion)

Alaska(hydrologic region)

Federal lands

White Mountain Native Corporation(ANCSA Village)

ANCSA Village NTVPIC(Type of land area)

NTVPIC(Federal land areas administered by NTVPIC)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Gold Primary

Comments on the commodity information

  • Gangue = carbonate
  • Gangue = white mica

Materials information

Materials Type of material
Arsenopyrite Ore
Gold Ore
Marcasite Ore
Pyrite Ore
Pyrrhotite Ore
Biotite Gangue
Chlorite Gangue
Fluorite Gangue
Plagioclase Gangue
Quartz Gangue
Mica Gangue
Titanite Gangue

Alteration

  • (Local) Quartz veining; alteration minerals in the host schist include plagioclase, chlorite, carbonate, white mica, biotite, titanite, and tourmaline.

Mineral occurrence model information

Model code 273
USGS model code 36a
Deposit model name Low-sulfide Au-quartz vein
Mark3 model number 27

Nearby scientific data

(1) -163.71425, 64.57532
ListMap

Economic information

Comments on the geologic information

  • Geologic Description = The Saddle prospect is known from the work of Ford (1993) and Ford and Snee (1996). A large gold and arsenic anomaly in soils led to its discovery. Gold-bearing quartz veins are localized in extensional joints that strike easterly and dip moderately to the south in quartz-muscovite schist. The host schist is similar to that at the nearby Bluff (SO135), Swede Creek (SO133) and Koyana Creek (SO136) lode prospects. This schist is a band intercalated in Paleozoic marble (Herried, 1965; Mulligan, 1971; Till and others, 1986). The veins are discontinuous and commonly less than 3 inches thick. Gold grades are irregularly distributed; vein intersections up to 3.3 feet across contain up to 1.8 ounces Au per ton. Minerals identified in the veins include arsenopyrite, biotite, carbonate, chlorite, fluorite, marcasite, plagioclase, pyrite, pyrrhotite, quartz, titanite, and white mica. Alteration minerals in the host schist include plagioclase, chlorite, carbonate, white mica, biotite, titanite, and tourmaline. The white mica in the veins is muscovite and that in the host schist is phengite. A sample of vein white mica gave a Ar/Ar plateau date of 109.1 +/- 0.2 Ma and metamorphic white mica in the host schist gave Ar/Ar total gas dates of 122.6 +/- 0.4 Ma and 122.4 +/- 0.2 Ma (Ford and Snee, 1996). This age is similar to that for some other lode gold deposits on southern Seward Peninsula. The southern Seward Peninsula lode gold deposits formed as a result of mid-Cretaceous metamorphism (Apodoca, 1994; Ford, 1993, Ford and Snee, 1996; Goldfarb and others, 1997) that accompanied regional extension (Miller and Hudson, 1991) and crustal melting (Hudson, 1994). This higher temperature metamorphism was superimposed on high pressure/low temperature metamorphic rocks of the region.
  • Age = Mid-Cretaceous, the age of some other lode gold deposits on southern Seward Peninsula. At this prospect, a sample of vein white mica gave a Ar/Ar plateau date of 109.1 +/- 0.2 Ma and metamorphic white mica in the host schist gave Ar/Ar total gas dates of 122.6 +/- 0.4 Ma and 122.4 +/- 0.2 Ma (Ford and Snee, 1996).

Economic information about the deposit and operations

Development status Prospect

Comments on exploration

  • Status = Active?

Mining district

District name Council

Comments on the workings information

  • Workings / Exploration = Surface soil sampling and some diamond drilling by BHP-Utah International was done here about 1990.

Reference information

Bibliographic references

Comments on the references

  • Primary Reference = Ford and Snee, 1996

General comments

Subject category Comment text
Deposit Model Name = Gold-bearing quartz veins along extension joints in quartz-mica schist; low sulfide-Au quartz vein (Cox and Singer, 1986; model 36a).

Reporter information

Type Date Name Affiliation Comment
Reporter 19-AUG-99 Travis L. Hudson Applied Geology

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.

Maps centered on this site

Authoritative Alaska resources

These are landing pages for further research — the state agencies don't currently expose per-mine deep links.