|Quadrangle map, 1:250,000-scale||TC|
|Quadrangle map, 1:63,360-scale||C-3|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The Two Mile prospect is about 1.8 miles west-northwest of the summit of Mount Fairplay. It is beside the Taylor Highway near the northeast corner of section 27, T. 22 N., R. 16 E. The location is accurate.|
Several companies have explored in the Mount Fairplay area since 1970 (Adams, 2009; Kerin, 1976). The history of the Two Mile prospect is uncertain but there are fairly well known prospects along the Taylor Highway to the north, the Fairplay prospect (TC008), and to the south, the Silver Lining prospect (TC 026), which was active as of early 2010. It is likely that the Two Mile prospect has been staked at one time or another but it status in early 2010 was unknown.
The Two Mile prospect is in core zone of the Mount Fairplay pluton whose outcrop area is about 4 miles in diameter (Foster, 1970; Kerin, 1976; Adams, 2009). The Mount Fairplay pluton is a Late Cretaceous to early Tertiary alkaline complex with well-developed ring structures. The pluton intrudes biotite schist and gneiss, probably of Mississippian and older age and bimodal felsic and mafic volcanic rocks, probably of Late Cretaceous age. The Mount Fairplay complex was emplaced in three phases between 59 and 67 Ma: 1) an early alkaline ring phase that consists of diorite and several syenite units on the north side of the complex; 2) a later alkaline ring phase that consists of several syenite units and perthosite on the south side of the complex; and 3) a calc-alkaline core phase that consists of hornblende-biotite quartz monzonite. The Two Mile prospect is in the hornblende-biotite quartz monzonite in the central part of the complex.The mineralization and hostrock at the Two Mile prospect are similar to that at the Silver Lining prospect (TC026) about a mile to the south (Adams, 2009). The mineralization consists of narrow gold-sulfide-quartz veins; that strike about N22E and dip 90SE; alteration and oxidation is pervasive. Two rock samples of quartz monzonite contained anomalous gold and sporadic, weak amounts of silver, copper, lead, molybdenum, thorium, uranium, and tungsten. Singer and others (1976) classified the deposit as a porphyry. However, more recent work by Adams (2009) suggest vein-type mineralization.
|Geologic map unit||(-142.276448265183, 63.6646668372618)|
|Mineral deposit model||Low-sulfide gold-quartz vein; porphyry deposit?|
|Age of mineralization||Late Cretaceous or early Tertiary based on the age of the host rocks.|
|Alteration of deposit||Unstated.|
|Workings or exploration||Several companies have explored in the Mount Fairplay area since 1970 (Adams, 2009; Kerin, 1976). The history of the Two Mile prospect is uncertain but there are fairly well known prospects along the Taylor Highway to the north, the Fairplay prospect (TC008), and to the south, the Silver Lining prospect (TC 026), which was active as of early 2010. It is likely that the Two Mile prospect has been staked at one time or another but it status in early 2010 was unknown. The exploration probably only consisted of some surface sampling and geologic mapping.|
|Indication of production||None|
Adams, David, 2009, Geologic report on the Drakan project, Fortymile Mining District, Alaska: Technical Report DK08 43-101 for Fire River Gold Corporation, 49 p. (posted on www.sedar.com, February 23, 2009).
Foster, H.L., 1970, Reconnaissance geologic map of the Tanacross quadrangle, Alaska: U.S. Geological Survey Miscellaneous Geological Investigations Map I-593, 1 sheet, scale 1:250,000.
Kerin, L.J., 1976, The reconnaissance petrology of the Mount Fairplay igneous complex: Fairbanks, University of Alaska, M.Sc. thesis, 95 p
Wilson, F.H., Smith, J.G., and Shew, Nora, 1985, Review of radiometric data from the Yukon crystalline terrane, Alaska and Yukon Territory: Canadian Journal of Earth Sciences, v. 22, p. 525-537.
|Reporters||D.J. Grybeck (Contractor, U.S. Geological Survey)|
|Last report date||4/2/2010|