Mindat Logo

Unnamed Occurrence (ARDF - TL053; near McDoel Peak), Yentna District, Matanuska-Susitna Borough, Alaska, USA

Latitude: 62°1'26"N
Longitude: 152°11'2"W
Location: Reed and others (1978, locality 38) show this occurrence in a tributary to Johnson Creek at about 2700 feet. The locality is approximately 3.5 miles east of McDoel Peak in the southeast quarter of Section 3, T. 22 N., R. 16 W., of the Seward Meridian.
Geology: Curtin, Karlson, O'Leary, Day, and McDanal (1978) report gold (+30 ppm) in bulk heavy-mineral concentrate samples from stream gravels at this locality. The area is underlain by hydrothermally altered Mesozoic graywacke and argillite (KJs) and one of the small bodies of diorite/granodiorite assigned to the Late Cretaceous (67.4 m.y.) Kichatna plutons (TKk) (Reed and others, 1978; Reed and Nelson, 1980). The creek contains abundant float of vein quartz. Gold was not detected from the quartz material, but Reed and others (1978) report a pan concentrate yielded more than 30 colors of fine gold. They indicate that similar altered zones are observed along Dollar (TL031) and Thunder Creeks (TL032, TL058), at the headwaters of Treasure (TL030), Dutch (TL033) and Bear Creeks (TL017).
Workings: Reconnaissance mapping (Reed and Nelson, 1980), stream silt and rock sampling (Curtin, Karlson, O'Leary, Day, and McDanal,1978) has been done by the U.S. Geological Survey. Prospecting and sampling was done by prospectors and claim owners in the 1980s. Current claim status is not known.
Age: Pleistocene; gold in sediment samples may have been derived from zones within the KJs that are hydrothermally altered by one of the Late Cretaceous diorite/granodiorite (67.4 m.y.) Kichatna plutons (TKk) mapped by Reed and Nelson (1980).
Alteration: The area is underlain by hydrothermally altered Mesozoic graywacke and argillite (Reed and others, 1978). Alteration mineralogy is not specified. However, based on its reported similarity to altered zones at Thunder Creek (TL032, TL058), it is most likely argillic alteration of Mesozoic sedimentary rocks.

Commodities (Major) - Au
Development Status: No
Deposit Model: Placer Au-PGE (Cox and Singer, 1986; model 39a).

References

Cobb, E.H., and Reed, B.L., 1980, Summaries of data on and lists of reference to metallic and selected nonmetallic mineral deposits in the Talkeetna quadrangle, Alaska: U.S. Geological Survey Open-File Report 80-884, 106 p. Curtin, G.C., Karlson, R.C., O'Leary, R.M., Day, G.W., and McDanal, S.K., 1978, Geochemical and generalized geologic maps showing the distribution and abundance of gold and silver in the Talkeetna quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-870-E, 2 sheets, scale 1:250,000. 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. Reed, B.L., and Nelson, S.W., 1980, Geologic map of the Talkeetna quadrangle: U.S. Geological Survey Miscellaneous Investigations Map I-1174, 1 sheet, scale 1:250,000. Reed, B.L., Nelson, S.W., Curtin, G.C., and Singer, D.A., 1978, Mineral resources map of the Talkeetna quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-870-D, 1 sheet, scale 1:250,000.

Mineral List

Gold


1 entry listed. 1 valid mineral.

The above list 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.
This page is currently not sponsored. To sponsor this page click here.


Mineral and/or Locality  
Search Google  
Copyright © Jolyon Ralph and Ida Chau 1993-2014. Site Map. Locality, mineral & photograph data are the copyright of the individuals who submitted them. Site hosted & developed by Jolyon Ralph. Mindat.org is an online information resource dedicated to providing free mineralogical information to all. Mindat relies on the contributions of thousands of members and supporters. Mindat does not offer minerals for sale. If you would like to add information to improve the quality of our database, then click here to register.
Current server date and time: December 20, 2014 20:11:43 Page generated: June 23, 2011 01:11:23
Mineral and Locality Search
Mineral:
and/or Locality:
Options
Fade toolbar when not in focusFix toolbar to bottom of page
Hide Social Media Links
Slideshow frame delay seconds