��������������������������������� ���������������������������� � �+6�/7 �+;�/� 4/2���/ "/4368 � $��7 6/4368 �7 46/����2+6� +2. �+7 238 ,//2 6/:�/;/. 036 -32036��8� ;�8� % # /3�31�-+� #96:/� /.�836�+� 78+2.+6.7 36 ;�8� 8�/ 368� �/6�-+2 #86+8�16+4��- 3./ 2� 97/ 30 86+./� 0�6�� 36 463.9-8 2+�/7 �7 036 ./7-6�48�:/ 496437/7 32�� +2. .3/7 238 ��4�� /2.367/�/28 ,� 8�/ % # 3:/62�/28 % # "$�$ $� �$"�" % # ��� #%"&� 2-�36+1/� �+7�+ Mount McKinley quadrangle Descriptions of the mineral occurrences shown on the accompanying figure follow. See U.S. Geological Survey (1996) for a description of the information content of each field in the records. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska. o o o o o o o o Distribution of mineral occurrences in the Mount McKinley 1:250,000-scale quadrangle, Alaska This and related reports are accessible through the USGS World Wide Web site http://ardf.wr.usgs.gov. Comments or information regarding corrections or missing data, or requests for digital retrievals should be directed to: Frederic Wilson, USGS, 4200 University Dr., Anchorage, AK 99508-4667, e-mail [email protected], telephone (907) 786-7448. This compilation is authored by: Charles C. Hawley Anchorage, AK Alaska Resource Data File This report is preliminary and has not been reviewed for conformity with U.S. Geologi- cal Survey editorial standards or with the North American Stratigraphic code. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. OPEN-FILE REPORT 2004-1200 Alaska Resource Data File MM001 Site name(s): Unnamed (north of Chilchukabena Lake) Site type: Occurrence ARDF no.: MM001 Latitude: 63.9829 Quadrangle: MM D-4 Longitude: 151.5474 Location description and accuracy: This occurrence is on the west side of the range of low hills that extends north from Chilchukabena Lake. The location is approximately at the midpoint of the boundary between sections 6 and 7, T 11 S., R. 20 W., Fairbanks Meridian. It is probably accurate within about 1000 feet. The location correponds to that of rock samples 5 and 6 of Hawley and Associates (1978). Commodities: Main: Be, Sn, Th, U Other: Pb, Zn Ore minerals: Gangue minerals: Feldspar, quartz Geologic description: A stock of McKinley-type granite (Reed and Lanphere, 1973) forms hills north of Chilchukabena Lake. The outcrop of the stock is about 3 miles long and 1.3 miles across; a small granite cupola crops out north­ east of the stock. Only the approximate southern two-thirds of the stock is in the Mt. McKinley quadrangle. In 1975, Hawley and Associates (1978) made an airborne radiometric survey of the area using a hand-held spectrometer. The aircraft flew about 150 feet above the ground at 90 miles per hour. Background radia­ tion over the granite mass was relatively high, partly due to its potassium feldspar content, but the radiation level was more than twice background over the cupola. Hawley and Associates collected samples of slightly altered, fine- and coarse-grained granite onn the south side of the stock (the location of this occur­ rence). The samples contained up to 50 ppm lead, 200 ppm zinc, 20 ppm beryllium, and 10 ppm tin. The granite at this site resembles the granite that hosts beryllium and base-metal prospects in the Boulder Creek or Tonzona area west of the old park boundary (Hawley and Associates, 1978, p. 4,124-126). Alteration: Weak argillic(?) alteration. Age of mineralization: The stock is tentatively correlated with McKinley-type granite, which is about 55 Ma (Reed and Lan­ phere, 1973). Deposit model: Weakly-altered tin(?) granite. Deposit model number (After Cox and Singer, 1986 or Bliss, 1992): Production Status: None Site Status: Inactive Page 2 Alaska Resource Data File MM001 Workings/exploration: Hawley and Associates (1978) conducted an airborne radiometric survey and reconnaissance-sampled the stock. Production notes: Reserves: Additional comments: The south part of the granite stock is in Denali National Park and Preserve. References: Reed and Lanphere, 1973; Hawley and Associates, 1978. Primary reference: Hawley and Associates, 1978 Reporter(s): C.C. Hawley Last report date: 05/07/01 Page 3 Alaska Resource Data File MM002 Site name(s): Quartz lode No. 1 Site type: Occurrence ARDF no.: MM002 Latitude: 63.9610 Quadrangle: MM D-1 Longitude: 150.3704 Location description and accuracy: The Quartz lode No. 1 occurrence is at an elevation of about 1500 feet on the west side of the canyon of Chitsia Creek. It is about 2 miles above the mouth of the canyon, near the center of section 18, T. 11 S., R. 14 W., Fairbanks Meridian. The location is probably accurate within 1500 feet. The occurrence is number 73 of Bundtzen, Smith, and Tosdal (1976), 32 of MacKevett and Holloway (1977), 53 of Hawley and Associates (1978), and 82 of Bundtzen (1981), and corresponds to an unnamed vein in Cobb (1980 [OFR 80-363]). Commodities: Main: Cu Other: Ag, Mo, Pb Ore minerals: Chalcopyrite, galena, malachite Gangue minerals: Quartz Geologic description: This deposit consists of a chalcopyrite- and galena-bearing quartz vein that cuts metarhyolite porphyry of the Upper Devonian and Mississippian Totatlanika Formation (Bundtzen, 1981). The vein is 2- to 3-feet thick, strikes about N 40 W, and dips 70 W. Rocks at the occurrence are coated with malachite. Grab sam­ ples assayed 0.58-1 percent copper, as much as 210 ppm lead, 51 ppm molybdenum, and 0.24 ounce of sil­ ver per ton. Bundtzen (1981) suggests that molybdenum is a characteristic trace element in deposits affili­ ated with the metarhyolite. The age of the vein is uncertain. It may be as old as Devonian or Mississippian, the depositional age of the Totatlanika Formation, or as young as Eocene (see MM091). Alteration: Oxidation of copper mineral. Age of mineralization: The age of the vein is uncertain. It may be as old as Devonian or Mississippian, the depositional age of the Totatlanika Formation, or as young as Eocene (see MM091). Deposit model: Polymetallic vein (Cox and Singer, 1986; model 22c). Deposit model number (After Cox and Singer, 1986 or Bliss, 1992): 22c Production Status: No Site Status: Inactive Page 4 Alaska Resource Data File MM002 Workings/exploration: The vein was discovered, mapped, and sampled by Bundtzen, Smith, and Tosdal (1976). There are no significant workings. Production notes: Reserves: Additional comments: The occurrence is in Denali National Park and Preserve. References: Bundtzen, Smith, and Tosdal, 1976; MacKevett and Holloway, 1977; Hawley and Associates, 1978; Cobb, 1980 (OFR 80-363); Bundtzen, 1981. Primary reference: Bundtzen, 1981 Reporter(s): C.C. Hawley Last report date: 02/06/01 Page 5 Alaska Resource Data File MM003 Site name(s): Unnamed (west-southwest of Chitsia Mountain) Site type: Occurrence ARDF no.: MM003 Latitude: 63.9610 Quadrangle: MM D-1 Longitude: 150.3411 Location description and accuracy: This occurrence is at an elevation of about 2300 feeton an unnamed ridge about 1.4 miles west-southwest of Chitsia Mountain. The location is accurate within 500 feet. It corresponds to number 33 of MacKevett and Holloway (1977), 74 of Bundtzen, Smith, and Tosdal (1976), 55 of Hawley and Associates (1978), and 83 of Bundtzen (1981), and is cited as an unnamed location by Cobb (1980 [OFR 80-363]). Commodities: Main: Pb Other: Ag, Au, Mo, Th, U, Zn Ore minerals: Cerussite, galena, limonite, sphalerite Gangue minerals: Quartz Geologic description: The country rock at this occurrence is metarhyolite porphyry of the Totatlanika Formation, a volcanic-rich unit of Late Devonian and Mississippian age (Bundtzen, 1981). The deposit is a mineralized quartz vein 1 to 3 feet thick that strikes N 20-40 W, and is almost vertical. The vein is oxidized to a lead- and silver- bearing limonitic boxwork (gossan) that contains cerussite and, probably, small amounts of remnant galena and sphalerite. Selected samples of the vein assayed 3.10-10.5 percent lead, 1.17-2.73 ounces of silver per ton, 0.24 percent zinc, 0.02 ounce of gold per ton, and up to 72 ppm molybdenum, 24 ppm uranium, and 15 ppm thorium (Bundtzen, 1981, table 10, number 83). Although speculative, the trace element geochemistry of this vein is at least permissive of a syngenetic or diagenetic origin, related to Upper Devonian or Mississippian Totatlanika volcanism (Bundtzen, 1981). An Eocene age is also possible (see MM091). Alteration: Oxidation of iron and lead minerals. Age of mineralization: Although speculative, the trace element geochemistry of this vein is at least permissive of a syngenetic or diagenetic origin, related to Upper Devonian or Mississippian Totatlanika volcanism (Bundtzen, 1981). An Eocene age is also possible (see MM091). Deposit model: Polymetallic vein (Cox and Singer, 1986; model 22c). Deposit model number (After Cox and Singer, 1986 or Bliss, 1992): 22c Production Status: No Site Status: Inactive Page 6 Alaska Resource Data File MM003 Workings/exploration: There are no workings. Production notes: Reserves: Additional comments: The occurrence is in Denali National Park and Preserve. References: Bundtzen, Smith, and Tosdal, 1976; MacKevett and Holloway, 1977; Hawley and Associates, 1978; Cobb, 1980 (OFR 80-363); Bundtzen, 1981; Cox and Singer, 1986. Primary reference: Bundtzen, 1981 Reporter(s): C.C. Hawley Last report date: 05/07/01 Page 7 Alaska Resource Data File MM004 Site name(s): Unnamed (on Chitsia Mountain) Site type: Occurrence ARDF no.: MM004 Latitude: 63.9643 Quadrangle: MM D-1 Longitude: 150.3046 Location description and accuracy: This 300-foot-long mineral occurrence (Cobb, 1980 [OFR 80-363]) is on a ridge crest about 2500 feet west-southwest of the top of Chitisia Mountain.