|Quadrangle map, 1:250,000-scale||IL|
|Quadrangle map, 1:63,360-scale||A-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This prospect is on or near the westernmost peak of Chenik Mountain at an elevation of about 3,000 feet. The site, which approximates the center of the outcrop area of the prospect, is about 1,700 feet west-northwest of peak 3117, in the E1/2 NE1/4 sec. 11, T. 11 S., R. 30 W., Seward Meridian. The site is location 22 of Detterman and Cobb (1972), and is accurate within 0.5 mile.|
This prospect is in the upper part of a Lower or Middle Jurassic quartz diorite batholith which intrudes older Jurassic, mafic and ultramafic rocks (Detterman and Reed, 1980). The mafic and ultramafic rocks form large roof pendants that probably are remnants of the roof of the batholith. Mafic and ultramafic rocks that crop out about a mile southeast of the site are downfaulted in a northeast-trending graben (Detterman and Reed, 1980).
The deposit consists of magnetite that is relatively abundant in diorite, gabbro, and hornblendite, and less abundant in quartz diorite (Detterman and Reed, 1980, p. B79). It occurs as disseminations, veinlets, lenses, and pods. In the hornblendite, magnetite makes up as much as 15-20 percent of the rock and occurs as grains in hornblende, along hornblende grain boundaries, and in lenses and irregular clots. In rocks other than hornblendite, magnetite generally makes up less than 10 percent of the rock.The Chenik Mountain deposit is probably large but relatively low-grade (Berg and Cobb, 1967). It was discovered by Pan American Petroleum Company following a regional aeromagnetic survey in 1964.
|Geologic map unit||(-154.27582648423, 59.2407162726678)|
|Mineral deposit model||Fe-Ti magmatic segregation deposit similar to Alaska PGE (Cox and Singer, 1986; model 9).|
|Mineral deposit model number||9|
|Age of mineralization||Jurassic.|
|Workings or exploration||The Chenik Mountain iron deposit was discovered by Pan American Petroleum Company after a regional aeromagnetic survey in 1964. Large magnetic anomalies revealed by the survey led to a staking rush by private interests.|
|Indication of production||None|
|Reserve estimates||The deposit is a possible large, low-grade, resource of titaniferous magnetite (Berg and Cobb, 1967).|
Additional commentsClaim names at this occurrence include: Gaec 1-8, Amak 98-104, and Snow Job 1-13 (McFaul and others, 2000).
Berg, H.C., and Cobb, E.H., 1967, Metalliferous lode deposits of Alaska: U.S. Geological Survey Bulletin 1246, 254 p.
Cobb, E.H., and Reed, B.L., 1981, Summaries of data on and lists of references to metallic and selected nonmetallic mineral occurrences in the Iliamna, Lake Clark, Lime Hills, and McGrath quadrangles, Alaska; Supplement to Open-File Report 76-485; Part A, Summaries to January 1, 1981: U.S. Geological Survey Open-File Report 81-1343-A, 25 p.
Cobb, E.H., and Reed, B.L., 1981, Summaries of data on and lists of references to metallic and selected nonmetallic mineral occurrences in the Iliamna, Lake Clark, Lime Hills, and McGrath quadrangles, Alaska; Supplement to Open-File Report 76-485; Part B, Lists of references to Januray 1, 1981: U.S. Geological Survey Open-File Report 81-1343-B, 20 p.
Detterman, R.L., and Cobb, E.H., 1972, Metallic mineral resources map of the Iliamna quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-364, 1 sheet, scale 1:250,000.
Detterman, R.L., and Reed, B.L., 1980, Stratigraphy, structure, and economic geology of the Iliamna quadrangle, Alaska: U.S. Geological Survey Bulletin 1368-B, 86 p.
MacKevett, E.M., Jr., and Holloway, C.D., 1977, Map showing metalliferous and selected non-metalliferous mineral deposits in the eastern part of southern Alaska: U.S. Geological Survey Open-File Report 77-169-A, 99 p., 1 sheet, scale 1:1,000,000.
|Reporters||C.C. Hawley, Hawley Resource Group, Anchorage, Alaska|
|Last report date||6/11/2003|