|Quadrangle map, 1:250,000-scale||DN|
|Quadrangle map, 1:63,360-scale||C-2|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The Little Maud prospect (Cobb, 1980 [OFR 80-363]) is on the southwest crest of Quigley Ridge at an elevation of about 2850 feet. It is about 0.25 mile south-southwest of the center of section 12, T. 16 S., R. 18 W., Fairbanks Meridian. The location is accurate within 300 feet. The prospect corresponds to claim number 14 of Hawley and Associates (1978); it is included with the Francis mine (DN124) in location 31 of Thornsberry, McKee, and Salisbury (1984), and in location 23 of Bundtzen (1981).|
Geologic descriptionThe country rocks at the Little Maud prospect are metafelsite and graphitic phyllite of the Spruce Creek sequence (Bundtzen, 1981; Thornsberry, McKee, and Salisbury, 1984). The deposit consists of mineralized quartz-calcite veins and breccia zones that cut graphitic schist (phyllite) and quartz schist, units that appear to be folded at an angle to the east-northeast trend of the Kantishna antiform (DN091) (Seraphim, 1962; Hawley and Associates (1978, fig. 4.1-1(A)-3). The veins strike NE and dip steeply. Davis (1923, p. 125) reported that an 18-inch-thick quartz-tetrahedrite vein was trenched immediately east of the Francis claim end line. A 13-foot-thick quartz vein, exposed in two trenches just north of the side line between the Little Maud and the Silver Pick (DN120) claims, strikes N 55 E. The vein contains pods and masses of fine-grained galena cut by veinlets of chalcopyrite. In one trench, the vein had a weighted average assay of 0.107 ounce of gold per ton and 53.3 ounces of silver per ton; in the other, the weighted average assay was 0.115 ounce of gold per ton and 22.6 ounces of silver per ton (Wells, 1933, p. 369). In 1983, The U.S. Bureau of Mines diamond-drilled this vein (Thornsberry, McKee, and Salisbury, 1984). The hole (K-5) cut a 31.5-foot-thick section of oxidized, quartz-calcite breccia containing arsenopyrite and small amounts of pyrite, chalcopyrite, sphalerite, and galena. The full 31.5-foot section assayed 0.022 ounce of gold per ton, 1.16 ounces of silver per ton, and 2.98 percent arsenic. The best 3.8-foot intercept assayed 0.082 ounce of gold per ton, 8.67 ounces of silver per ton, and 1.05 percent arsenic. Lead and zinc contents were in the 0.X percent range.
|Geologic map unit||(, )|
|Mineral deposit model||Polymetallic vein (Cox and Singer, 1986; model 22c).|
|Mineral deposit model number||22c|
|Age of mineralization||The deposit is assumed to be Eocene (see record DN091).|
|Alteration of deposit||Oxidation of iron minerals.|
|Workings or exploration||The Little Maud claim was prospected in about 1920 (Davis, 1923), and there was some activity in the 1930s (Wells, 1933). The Little Maud - Silver Pick - Francis claim area was extensively studied by Moneta-Porcupine in about 1960 (Seraphim, 1962). The area was also investigated by Hawley and Associates (1978) and Bundtzen (1981), and in 1983, the U.S. Bureau of Mines drilled one core hole (K-5) (Thornsberry, McKee, and Salisbury (1984, v. 2, occurrence 31).|
|Indication of production||Undetermined|
Additional commentsThe claim is in Denali National Park and Preserve.
Bundtzen, T.K., 1981, Geology and mineral deposits of the Kantishna Hills, Mt. McKinley quadrangle, Alaska: M. S. Thesis, University of Alaska, College, Alaska, 238 p.
Cobb, E.H., 1980, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Mount McKinley quadrangle, Alaska: U. S. Geological Survey Open-File Report 80-363, 150 p.
Cox, D.P., and Singer, D.A., eds., 1986, Mineral deposit models: U.S. Geological Survey Bulletin 1693, 379 p.
Davis, J. A., 1923, The Kantishna region, Alaska, in Stewart, B. D., Annual Report of the Mine Inspector to the Governor of Alaska, 1922: Alaska Division of Geological and Geophysical Surveys AR-1922.
Hawley, C. C. and Associates, Inc, 1978, Mineral appraisal of lands adjacent to Mt. McKinley National Park, Alaska: U. S. Bureau of Mines Open-File Report 24-78, 275 p. (paged by sections).
Seraphim, R.H., 1962, Kantishna District: Alaska Division of Mines and Minerals Miscellaneous Report 193-3, 11 p., 10 sheets.
Thornsberry, V. V., McKee, C. J., and Salisbury, W. G., eds, 1984, 1983 Mineral Resource Studies: Kantishna Hills and Dunkle Mine Areas, Denali National Park and Preserve, Alaska: U. S. Bureau of Mines Open-File Report 129-84. 3 Volumes: v. 1, Text; v. 2, Appendices; v. 3, Maps. Prepared by Salisbury & Dietz, Inc., Spokane, WA.
|Last report date||2/9/2001|