IDAHO GEOLOGICAL SURVEY IDAHOGEOLOGY.ORG DIGITAL WEB MAP 190 MOSCOW AND BOISE STEWART AND OTHERS

present in exposures in the southern part of the map. Quartzite is feldspar The Johnson Creek shear zone is a major regional structure (Lund, 2004). To PIONEER GROUP (CH0776) poor. Thickness unknown because of complex internal folding and the the south of the quadrangle it can be traced as a series of faults (Fisher and 19DS16 GEOLOGIC MAP OF THE YELLOW PINE QUADRANGLE, VALLEY COUNTY, IDAHO The Pioneer group is a prospected area located northeast of the mouth of presence of a foliation that may or may not be transposed bedding. Likely others, 1992; Stewart and others, 2018), none of which appear to be as equivalent to the quartzite and schist unit in the Stibnite roof pendant silicified as in the Yellow Pine area. One splay likely connects to the Dead- Riordan Creek. One Defense Minerals Administration (DMA) application Cambrian

CORRELATION OF MAP UNITS y mapped by Stewart and others (2016). wood fault, which is locally mineralized at and southwest of the Deadwood and one Defense Minerals Exploration Administration (DMEA) loan appli- i l t lower cation were made in the 1950s for claims in this area, details of which are

Mine (Kiilsgaard and others, 2006). To the north, north of the Red Mountain a b b

Zmsm Marble of Moores Station Formation (Neoproterozoic)—Discontinuous lenses available in Frank (2016). Prospects at slightly lower elevation were termed o qtzite David E. Stewart, Reed S. Lewis, Eric D. Stewart, and Zachery M. Lifton stockwork, the fault zone is intruded by voluminous Eocene dikes (Lund, r of buff to light-gray marble and lesser amounts of millimeter- to the Syringa Group (DMA Docket 1036). Information from DMEA Docket p 2005). Foliation in the Cretaceous intrusive rocks is locally well developed e centimeter-scale laminated calc-silicate rock within the schist-rich Moores but the dikes appear undeformed. The Fawn Meadow fault northwest of 2572 on the Pioneer Group indicates that overburden is extensive, and that i v 2021 Artificial Mass-movement Station Formation. Thickness as much as 40 m (130 ft). landslide activity is apparent. Small amounts of scheelite and stibnite are

Edwardsburg (Lewis and others, 2012) likely is part of the shear zone and R e l a t Deposits Alluvial Deposits Deposits Glacial Deposits one strand may connect beyond Fawn Meadow to the Golden Hand mine. reported from calc-silicate rocks in granitic gneiss. Zmscs Calc-silicate of Moores Station Formation (Neoproterozoic)—Discontinuous m Qal Holocene lenses of millimeter- to centimeter-scale laminated calc-silicate rock within Qaf Qls QUATERNARY the schist-rich Moores Station Formation. Thickness as much as 40 m (130 Qg Qgo Pleistocene SALT CREEK FAULT B Qg D O_mm ft).

Kgd 20 Ÿ 0 500 1000 1500 2000 2500 3000

Ta Zqp ª Kgdsi Ÿ 22 Kgd Ts Date (Ma)

5 O_mq? The Salt Creek fault, striking northeast and dipping steeply to the northwest, C REFERENCES

TrŸ Ÿ Kgd ¬

C

Zqp BŸ Ÿ O_mm shows evidence of both normal and left-lateral motion in the adjoining Ÿ Zmss? Tr Ÿ Þ Ÿ 12 O_mmq Ÿ Tertiary Sedimentary Deposits

Ÿ Þ Zqp ª Ÿ

Tr 10 Þ Ÿ D Stibnite quadrangle to the east (Stewart and others, 2016). In the Yellow Ÿ C DETRITAL ZIRCON DATA

Ÿ Tr Qg ¬ Bennett, E.H., and Gillerman, V.S., 1992, Mining and minerals in Idaho,

Ÿ D Ÿ CENOZOIC Pine quadrangle, the motion is less certain, but down-on-the-northwest 19DS28

Td Zqp ª O_mm Ts 1991, Unpublished manuscript, Idaho Geological Survey, Available at

Ÿ ¬ Missouri Ridge ¶ normal motion is suspected. Tr Ÿ

Zqp https://www.idahogeology.org/current-historic-mining-activity (accessed Cambrian

76 22 fault Quartzite samples for detrital zircon dating were collected from five locali- y C

C

22 C ª 8 August 2020).

39 i l t

40 ¬ TERTIARY ties within the southern part of the quadrangle (see Symbols and Figure 2).

87 C lower C ª B Bennett, E.H., and Gillerman, V.S., 1993, Mining and minerals in Idaho, a b C 6 40 Intrusive Rocks Results from one locality to the north along Profile Creek has been reported

70 Tr Ÿ 24 39 B b

Ÿ 1992, Unpublished manuscript, Idaho Geological Survey, Available at o Ÿ r qtzite C Ÿ previously (Stewart and others, 2016, sample 10RL893). U-Pb ages report- B 16 p Ÿ Ÿ ‰ 35 MINES AND PROSPECTS

B https://www.idahogeology.org/current-historic-mining-activity (accessed e B 23 O_mm 40 Tr Tqd Td Ta Eocene ed here were obtained by Jim Crowley using laser-ablation ICP-MS meth- B ª 40 i v Kgd C 22 B ods at Boise State University. Overall, the detrital zircon results support the 29 May 2020). C 55 C Þ B B Bennett, E.H., and Gillerman, V.S., 1997, Mining, Minerals, and the Environ-

Mines and larger prospects present in the quadrangle are described below. R e l a t

ª Zmss 28 conclusion that all the metasedimentary rocks in the Yellow Pine quadran-

12 O_mmq Kgdsi Kgd C ¬ Most are in the west, in or near the Johnson Creek shear zone. In addition ment in Idaho, 1994 Idaho Geological Survey Staff Report S-97-22, 81 p. 87 B 20 gle are Neoproterozoic to Paleozoic. N 7 CRETACEOUS MESOZOIC to the references below, unpublished maps and documents for individual Bookstrom, A.A., Johnson, B.R., Cookro, T.M., Lund, K., Watts, K.C., King, ª Tr Ÿ Zqp 14 Kgdo Kgdp properties are available by examining “Property Details” through the H.D., Kleinkopf, M.D., Pitkin, J.A., Sanchez, J.D., and Causey, J.D., 1998, Qls N Ÿ Qaf 18 Missouri Ridge Ÿ Profile Creek fault Two samples from the lower quartzite unit (Clq) have similar detrital zircon interactive map (“Mines” web app) on the Idaho Geological Survey website Potential Mineral Resources, Payette National Forest, ID—Description Tqd B ª fault

15 Zqp B ages (19DS16 and 19DS28, Figure 2). Most of the grains are between 1,700 (https://www.idahogeology.org/webmap). Property codes (e.g. CH0766) and probabilistic estimation: U.S. Geological Survey Open-File Report 0 500 1000 1500 2000 2500 3000

¬ ª ¡

¡

B ¡ are given below to assist with website searches. 98–219–A, 254 p. Date (Ma)

¬ and 1,850 Ma, matching results from the lower quartzite in the Stibnite area 23 ¡

7 C

Kgdsi ¡ Metasedimentary Rocks

Kgd Þ Qls ¡ to the east reported by Stewart and others (2016). In contrast, two samples Box, S.E., Wintzer, N.E., Vazquez, J.A., 2016, New SHRIMP U-Pb ages 86 Þ ¡ C ª Zmss

Þ ¡ bearing on Late Cretaceous evolution of central Idaho: Geological 26 Þ O_mq from differing quartzite intervals within the schist of the Moores Station

Þ ª ¡ 55

¡ CAMBRIAN/ 19DS26

¡ Society of America Abstracts with Programs, v. 48, Available at: https://g-

¡ C Formation (19DS26 and 19DS27) have dissimilar detrital zircon ages, KISSINGER QUARTZ CREEK TUNGSTEN MINE (CH0766)

B ¡

Td ¬ 20 ¡ Qls O_mmq O_mm ORDOVICIAN B sa.confex.com/gsa/2016RM/webprogram/Paper276025.html (accessed AB ¡ PALEOZOIC possibly due to unrecognized complexity in this formation. A peak at 626 32 ¡ C Zqp ª 15 Neoproterozoic

¡ 10 Located on the west side of Quartz Creek, this deposit was worked for 24 August, 2020).

¡ Ma in results from sample 19DS27 provides a clear maximum depositional y B ª

¡ 30 ª ª C88 ¡ _lq scheelite in the 1950s. Notes and a sketch map by Benjamin Leonard from Buehler, A.R., Linne, J.M., Causey, J.D., and M.S. Miller, 1993, Mineral Moores Kissinger 39 C CAMBRIAN age and is similar to the 624 Ma peak obtained from a sample of quartzite i l t 18 10

Quartz Creek 40 1956 (Book 2, U.S.G.S. Field Records Library, Denver, CO) indicate it was resources of the Secesh study area, Idaho and Valley counties, Idaho: a b

¡ B C within the Moores Station Formation southwest of Moores Station in the b Station Fm.

¡ ª 10 Zlcf o

¡ ª r C staked in 1952 and that the initial operation was placering of rubble from

tungsten mine C ª U.S. Department of the Interior, Bureau of Mines, Mineral Land Assess- ª ¡ ª

ª Gospel Peaks area (Lewis and others, unpublished mapping). Sample p

¡ Qls ¡ Qls

e 7 48

² the hill slope above the present adit. In 1956, 210 lbs. of WO3 concentrate ment Open-File Report 9-93, 54 p., 5 Appendices.

ª 19ES05 from a quartzite within a carbonate-rich part of the Moores Station

85 80 B i v

25 ª

ª ª Zqp

C NEOPROTEROZOIC was shipped. It reportedly ran 61.65% WO . Two samples of

¬ Zmss 3 Crowley, F.A., 1983, Geology and geochemistry 1982, Golden Gate proper- Ts ª Formation has yet another set of ages, many Archean, but including some

7

C 7

C85 10RL893B ª arsenopyrite-bearing ore taken in the adit contained 0.10 and 0.02 oz gold, ty, Valley County, Idaho, for Golden Gate Corporation: Idaho Geological R e l a t 35 ª as young as 690 Ma. Additional mapping and detrital zircon sampling

C70 ~ 10 Zmsm Zmss Zmscs 6.0 and 10.1 oz silver, and 0.5 and 6.2 percent lead. A map made in July Kgd !5 10 ª would be required to better understand these age differences. The previous- Survey Mineral Property File MPF-CH0771_002. Available at https://ida-

Tr C ª Whiskey Creek Ÿ 1972 by Benjamin Leonard (USGS Field Records Library) indicates that

37 45 ‰ C 22 ly reported Profile Creek sample (unit Zqp) has major populations at hogeomap.nkn.uidaho.edu/Data/MineDocs/CH0771_002.pdf (accessed ¬

Ÿ

Kgd Tr B ª fault there were two short adits; the lower, longer adit was about 70 ft in length.

Ÿ B´ 29 May 2020). C ª 1,000-1,200 and 1,400-1,500 Ma (Stewart and others, 2016), similar to C Ÿ 25 Gammons (1988) reported a maximum 40Ar/39Ar age of 57.0 ± 0.2 Ma age Erdman, J.A., Leonard, B.F., and McKown, D.M., 1985, A case for plants in 40 Ÿ Þ ages from other Neoproterozoic rocks in the region reported by Yonkee and ~ 10Þ Qal B Þ others (2014). on sericite from altered granodiorite adjacent to scheelite-rich exploration--Gold in Douglas Fir at the Red Mountain stockwork, Yellow 0 500 1000 1500 2000 2500 3000 Þ Date (Ma) Ts? 14 Þ quartz-carbonate veins. A thesis by Petersen (1984) provides additional Pine District, Idaho, in McIntyre, D.H., ed., Symposium on the geology

75 Þ BÞ Qaf

85 information on the property. and mineral deposits of the Challis 1° quadrangle: U.S. Geological Kgdsi B 57 Zqp C 20 INTRODUCTION Td Dacite dikes (Eocene)—Medium-gray to dark green-gray, fine-grained to Qgo C Profile Creek fault Zqp Survey Bulletin 1658 A-S, Chapter L, p. 141-152. N B aphanitic dacite with sparse phenocrysts of plagioclase, biotite, and Ta Fisher, F.S., D.H. McIntyre, and K.M. Johnson, 1992, Geologic map of the 19DS27 Johnson Creek shear zone Qls 17 hornblende. Large dike in northwest corner of map contains numerous STRUCTURE Johnson Creek shear zone ‰ Ÿ B Qal The Yellow Pine area is underlain by Cretaceous intrusive rocks GOLDEN GATE MINE (CH0771) Challis 1° x 2° quadrangle, Idaho: U.S. Geological Survey Miscellaneous Ÿ inclusions of Cretaceous granodiorite (Kgd). 26 ¬ representing at least two distinct pulses of magma that intruded folded and Neoproterozoic Investigations Series Map I-1819, scale 1:250,000. y

Ÿ Qal

² ¬ Ts C A The deformational history of the Yellow Pine quadrangle is complicated and C The Golden Gate mine is located on the ridge southeast of Yellow Pine. i l t Kgd B 18 metamorphosed sediments of Neoproterozoic and Paleozoic age. Frank, D.G., 2016, Historical files from Federal Government mineral explora- 12 25 Tqd Quartz diorite (Eocene)—Dark-gray, fine-grained, non-porphyritic biotite- and Moores

N Þ includes episodes of contractional folding and faulting, transpressional According to Crowley (1983), J. J. Oberbillig located the present Golden a b

Volumetrically minor dikes and small intrusions of the Eocene Challis tion-assistance programs, 1950 to 1974: U.S. Geological Survey Data b

˜ ¡ B Zmss 85 ¡¡¡ hornblende-biotite quartz diorite. Present in a single small stock west of o

strike-slip faulting, as well as extension and normal faulting. The area lies r Qal ˜ ¡¡¡ Gate claims in the 1920s, but tungsten was not discovered until the 1950s. Station Fm. ª magmatic event are also present. North-northeast and northeast-trending Series 1004: https://pubs.usgs.gov/ds/1004/ds1004_id.htm (accessed 29 p ˜ ¡ 7 Profile Creek. m North Shore Qaf ¡ Qls faults are the primary structural feature and include the regionally extensive along the eastern margin of the Cretaceous Idaho batholith. Much of the Leonard (1992) described the deposit as a small scheelite-bearing lens in a e

25 May 2020). i v prospects C 28B ª Johnson Creek shear zone along the western part of the quadrangle where contractional deformation likely preceded and was synchronous with the large quartz lode in the Johnson Creek-Quartz Creek silicified zone. The Gammons, C.H., 1988, Studies in hydrothermal phenomena: (1) The solubili- X W Qls C Kgd

X W 7

35 30 Granodiorite (Cretaceous)—Primarily light-gray, medium- to locally

Qaf emplacement of the early metaluminous suite of the Idaho batholith lens, striking N40° E, and dipping about 70° SE, is 150 ft long and 12 to 15 R e l a t

X W 20 ª 30 28 ª ª it locally hosts gold-tungsten-antimony mineralization. Quaternary surficial ty of silver sulfide in aqueous sulfide solutions to 300°C; (2) A paragene- B B coarse-grained equigranular to porphyritic biotite granodiorite, but X W B Qaf Qal 82 30 (100-85 Ma, Gaschnig and others, 2010). Both the metasediments and the ft wide. As noted by Leonard (1992), the strike is oblique to the locally N 30 22 25 C deposits occur in stream beds and in glaciated areas and several large includes white to light-gray, generally fine- to locally medium-grained sis and fluid inclusion study of polymetallic vein mineralization in the Big N ‰ X W B Idaho batholith rocks have been affected by Cretaceous and younger prevailing north trend of the silicified zone and the dip departs substantially Qg B B landslides are present. equigranular biotite-muscovite leucocratic granite. Isolated flakes of Creek mining district, central Idaho: Pennsylvania State University Ph.D. C Qal 28 C C 25 20 movement along the Johnson Creek shear zone in the western part of the from the dominantly vertical dip of the zone. Drill cores showed several ft

Qgo Ta Ÿ B muscovite as large as 2 mm comprise as much as 2 percent of the rock thesis, 337 p. ‰ 20 B Geologic mapping was conducted by David Stewart and Eric Stewart quadrangle. Extension was likely synchronous or post-dated the eruption of of clay-rich gouge at the footwall of the orebody. Leonard described the Ÿ

X W X W Gaschnig, R.M., Vervoort, J.D., Lewis, R.S., and McClelland, W.C., 2010, Tr 25 A32 locally, particularly in the western part of the area. Plagioclase feldspar is Ÿ Ts? B largely during the summer of 2019. In addition, unpublished mapping by the Eocene Challis volcanics, remnants of which are exposed 4 km (2.5 mi) scheelite as irregularly distributed specks, disseminated grains, thin 0 500 1000 1500 2000 2500 3000

Kgd ‰ Ÿ 20 the principle constituent, followed by quartz comprising more than 20 Migrating magmatism in the northern US Cordillera: in situ U-Pb

N Zqp 33 Date (Ma) ¡ Benjamin F. Leonard of the U.S. Geological Survey (1956-1965; on file in northeast of the map. This extension also formed a series of veinlets, and networks of replacement veinlets in argillic, commonly slight-

¡¡ Qal geochronology of the Idaho batholith: Contributions to Mineralogy and ¡ percent, and potassium feldspar. Biotite is present as small (<2 mm) 28 Qal northeast-striking normal faults within the batholith and roof pendants. ly vuggy vein quartz; as crusts of small crystals lining some vugs; and a Qal B B the USGS Denver Field Records Library) was utilized to further constrain well-disseminated flakes that make up less than 10 percent of the rock. Low Petrology, v. 159, p. 863-883. ‰ Qls ¬ B 32

Ÿ the field observations. Many of the foliations shown on the map east of cement for finely brecciated quartz. A moderate to large amount of clay,

Ta reek fault magnetite content reflected in low magnetic susceptibility values (typically Gaschnig, R.M., Vervoort, J.D., Tikoff, B., and Lewis, R.S., 2017, Construction

Ÿ C 19ES05 ² Golden e C Johnson Creek in this area are taken from his field maps and notebooks. chiefly illite, is present in the host rock. il 41 less than 0.1; see Table 1 and Symbols). Locally displays a weak to strong RIORDAN CREEK SYNCLINE and preservation of batholiths in the northern U.S. Cordillera: Litho- Gate mine Zqp Zachery Lifton used lidar imagery to delineate the landslides, and Reed Prof foliation. Locally porphyritic with euhedral potassium feldspar crystals as sphere, v. 9, no. 2, p. 315-324. Neoproterozoic 80 Lewis compiled all mapping in 2020. The work is part of a long-term

¬ much as 3 cm in length. U-Pb zircon LA-ICPMS age determination on The Riordan Creek syncline consists of two segments. The northwest Gillerman, V.S., Schmitz, M.D., Benowitz, J.A., and Layer, P.W., 2019, Geolo- y Qaf According to Crowley (1983) several thousand tons of scheelite ore was Moores

Whiskey Creek mapping effort by the Idaho Geological Survey in the Big Creek-Yellow sample from 0.6 km (2,000 ft) west of the town of Yellow Pine is 78.2 ± 1.8 segment plunges southeast and is cored by the Neoproterozoic Fern gy and temporal evolution of alteration and Au-Sb-W mineralization, i l t

~ C fault Pine area and is the fifth map completed (Figure 1). Stratigraphic terminolo- produced from a small open pit in 1956 and 1957 but most of the ore was a b marble. To the southeast its plunge shallows, and the syncline is cored by Stibnite mining district: Idaho Geological Survey Bulletin 31, 149 p. b 7 C Ma (Gaschnig and others, 2017). Volumetrically subordinate leucocratic Station Fm. ¬ 30 o gy for the metasedimentary rocks here follows that of Stewart and others stockpiled. In 1965 an additional small production was made. The deposit r C80 granite is equigranular, light gray, generally fine to locally medium grained. the Cambrian lower quartzite unit (Clq). Where upright in the northwest the Kiilsgaard, T.H., Stanford, L.R., and Lewis, R.S., 2006, Geologic map of the p 55 Zqp (2016), much of which is based on the work by Smitherman (1985) in the was mined in a small way in 1972 and the ore was treated at the Oberbillig e ~ C It contains subequal amounts of quartz, plagioclase, and potassium axis is well constrained but to the southeast, where it appears to be Deadwood River 30 x 60 minute quadrangle, Idaho: Idaho Geological i v 50 mill (Golden Gate mill) west of Antimony Camp (Leonard, 1992). Accord-

30 B ª ª Stibnite area to the east. overturned to the southwest, the location of the axis is highly speculative. Survey Geologic Map 45, scale 1:100,000. X W

Kgdsi X W ª ª ª feldspar. Muscovite occurs as disseminated flakes as much as 2 mm in size, ª 38 ª ing to Leonard (1992), two thousand tons of ore mined underground in R e l a t

ª ª comprising a maximum of 5 percent of the rock. Biotite is rare. Occurs as The unusual thickness of the Clq unit may be a result of this overturning, as Le Bas, M.J., and Streckeisen, A.L., 1991, The IUGS systematics of igneous ª 1980 was hauled to the Oberbillig mill and stockpiled there. In addition, dikes cutting both metasedimentary country rock and biotite granodiorite. well as a flattening of the fold axis. Although less likely, the thickness may rocks: Journal of the Geological Society of London, v. 148, p. 825-833.

7,000 tons was piled at the mine (oral communication to Benjamin Leonard Ÿ Þ Þ Qls Zmss Qls alternatively be a result of movement along unmapped thrust faults. If an Lane, E.W., 1947, Report of the subcommittee on sediment terminology; X W A X W Gillerman and others (2019) report a U-Pb TIMS age on “alaskite” as 83.6

Ÿ Þ Þ ª by Harlow Oberbillig, 1992). Harlow Oberbillig drilled seven holes in the Ÿ

Ÿ ± 0.1 Ma collected from a drill hole north of the Yellow Pine pit, 3 km (1.9 overturned fold is the correct interpretation, its sense of vergence is similar Transactions of the American Geophysical Union, v. 28, no. 6, p. Zqp ¡

Ÿ SYMBOLS Golden Gate area in 1994 (Bennett and Gillerman, 1997). Additional X W X W

ª ¡ ¡ ¡ 7 A´ to that of the overturned Garnet Creek syncline in the Stibnite area 4 km 936-938.

Ta ¡¡¡¡ mi) to the east that may be of similar age to some of the leucocratic granite ¡ ¡ ¡ information on work at the mine and mill is provided by Oberbillig (1980). 0 500 1000 1500 2000 2500 3000 ¡

¡ ¡

Ÿ (2.5 mi) to the east of this map (Stewart and others, 2016). Lewis, R.S., Kiilsgaard, T.H., Bennett, E.H., and Hall, W.E., 1987, Lithologic

89 ¡ cutting the country rocks in the Yellow Pine quadrangle. It is too old,

¡¡ Crowley (1983) discusses soil sampling and the gold potential of the Date (Ma)

C Ÿ ¡

ª

¡ Contact: dashed where approximately located. Ta ¡ however, to represent the leucocratic rocks cutting the biotite granodiorite and chemical characteristics of the central and southeastern part of the 7 property. 50 ‰ Qg C southern lobe of the Idaho batholith, in Vallier, T.L., and Brooks, H.C., X W ‰ X W Figure 2. Probability density plots of LA-ICPMS U-Pb dates from detrital zircons

² ª Qls 55 unit if the age of that unit is 78 Ma. ‰ O WHISKEY CREEK FAULT eds., Geology of the Blue Mountains Region of Oregon, Idaho, and from five quartzite samples in the Yellow Pine quadrangle. Locations (NAD27):

Ÿ ‰ Qls 5 ~ Reactivated strike-slip fault with later normal motion: dashed where Kgdsi 19DS16 = 44.8752°N, 115.3949°W; 19DS28 = 44.8911°N, 115.4587°W; 19DS26 X W 47 ¬ Silicified granodiorite (Cretaceous)—Weakly to strongly silicified biotite Washington: U.S. Geological Survey Professional Paper 1436, Chapter 9, TaŸ Whiskey Creek Kgdp The Whiskey Creek fault is a low-angle structure that places the Moores

‰ ª approximately located; dotted where concealed; ball and bar on ANTIMONY RIDGE MINE (CH0773) ÞN Qg Qls granodiorite along the Johnson Creek shear zone. See Structure section for p. 171-196. = 44.8844°N, 115.4995°W; 19DS27 = 44.9024°N, 115.4802°W; 19ES05 = X W Zqp fault Qls? ª downthrown side. Station Formation (Zms) over the quartzite of Profile Creek (Zqp). It crosses 44.8943°N, 115.3968°W; 10RL893 = 44.9748°N, 115.4198°W. Analytical Þ ª ª X W additional description and discussion. X W Kgd ª ª Leonard, B.F., 1992, The Golden Gate tungsten deposit and metal anomalies X W ª the quadrangle from northeast to southwest and is presumably intruded out The Antimony Ridge mine (also known as the Babbitt Metal group and work was by Jim Crowley at Boise State University. Plotted with Isoplot 3.0 C ‰ Zmss Kgdo Zmss in nearby soils and plants, Yellow Pine District, Valley, County, Idaho: X W ª by Cretaceous granitic rocks. The fault is roughly parallel to bedding in the Kgdsi 70 Zmss ¬ Normal fault: dashed where approximately located; dotted where Kgdo Older granodiorite (Cretaceous)—Light- to medium-gray biotite granodiorite Hanson antimony mine) east of Johnson Creek was described by Schrader (Ludwig, 2003).

Kgd ¬ quartzite of Profile Creek. The fault zone is characterized by a broad zone and Ross (1926), who noted the country rock is granodiorite and the depos- Unpublished manuscript, U.S. Geological Survey Field Records Library,

X W concealed; ball and bar on downthrown side. in eastern part of map. Similar to Kgd, but typically contains more biotite 7 Qls Denver, CO, Box 488, 32 p.

C Qg ª of ductile deformation and may also have localized zones of brecciation its are associated with pegmatitic dikes, the principal gangue mineral being Antimony ‰ N 80 and muscovite is absent. Local biotite-rich zones are present and magnetite

‰X W C35 ª ª Thrust fault: dashed where approximately located; dotted where and iron staining. No kinematic indicators were observed. The Whiskey vein quartz. We speculate here that the mineralization is along a narrow Leonard, B.F., and Erdman, J.A., 1983, Preliminary report on geology,

7 Whiskey Creek fault ª Ridge mine 35 Kgdp content is intermediate between Kgd and Kgdp (Table 1). Age is slightly

¡¡¡ ª geochemical exploration, and biogeochemical exploration of the Red

‰ Qls ¡ ¡ 34 ª concealed; teeth on upper plate. Creek fault is interpreted to record thrust motion; however, there is uncer- northeast-striking fault. The Idaho Mining Co. is said to have shipped 40

¡ younger than Kgdp. In the Stibnite area to the east Box and others (2016) 7 C

ª X W

¡ Mountain stockwork, Yellow Pine district, Valley County, Idaho: U.S.

œ tainty due to the ambiguity in the stratigraphic location of the quartzite of tons of ore in 1916 and 17. Crowley (1983) stated that J. J. Oberbillig ‰ C B44 ª C report a zircon age of 87.2 ± 0.7 Ma from rocks mapped as biotite granodi-

7 Qaf Qgo ‰ 25 45 B46 ª ª C Geological Survey Open-File Report 83-151, 49 p. ‰ B 72 Syncline axial trace; dotted where concealed; arrow shows plunge Profile Creek. Alternative explanations include 1) low-angle normal shipped several additional carloads in 1926 and 1927, but it was not until X W X W

X W orite by Stewart and others (2016). In addition, a preliminary U-Pb zircon

Qg ‰ ª 70 ¶ Lewis, R.S., D.E. Stewart, and E.D. Stewart, 2012, Geologic map of the Big

80 7 direction. X W

X W faulting; and 2) a depositional contact along which deformation was

C X W 24 1939 or 1940 when the U. S. Bureau of Mines discovered larger quantities

73 ‰ Qls ª age of 91.2 ± 2.2 Ma reported by Stewart and others (2016) from biotite

X W 70 30 ´ Creek quadrangle, Idaho and Valley counties, Idaho: Idaho Geological C ª

7 Þ X W granodiorite core near the Meadow Creek mine was later revised to 89.9 ± concentrated because of the ductility contrast of the upper and lower units. of stibnite that larger scale production began. He also noted that during C C

29 70 m C30 ª Overturned syncline axial trace; dotted where concealed. Survey Digital Web Map 143, scale 1:24,000.

Þ X W 7 Þ World War II about forty carloads of stibnite were shipped from the claims 7 ‰ 1.7 (Gaschnig et al., 2017). Both ages are thus older than the 78 Ma biotite 30C C ¡ C ª C Lund, K., 2004, Geology of the Payette National Forest and vicinity, 89 Qaf ¡ ¡ 20 and that in the 1960s several more carloads were hand cobbed from the

C 70 ¡¡ 35 granodiorite (Kgd of this map) in the west in the vicinity of Yellow Pine.

19 B ¡ Zmss B X W west-central Idaho: U.S. Geological Survey Professional Paper 1666, 2 Qaf ¡ A Strike and dip of bedding. dumps.

52 35 ¡ Qls 64 MISSOURI RIDGE FAULT

13 Þ Kgd Qls ¡ ª ª plates, scale 1:100,000; 89 p.

30 ¡ X W Kgdp

Þ Qls ¡ ª Porphyritic granodiorite (Cretaceous)—Medium-gray to gray and pink, medi- 7 7 ª Strike and dip of bedding; ball indicates bedding known to be upright. Lund, K., J.N. Aleinikoff, K.V. Evans, E.A. duBray, E.H. Dewitt, and D.M. 7 A poorly understood northwest-striking fault in the northeast corner of the B C C 36 um-grained, typically porphyritic, biotite granodiorite and tonalite. Þ ª

75 Þ 50 C 50 X W Unruh, 2009, SHRIMP U-Pb dating of recurrent Cryogenian and Late

C ² Zqp 46 Includes numerous unmapped dikes of leucocratic granite. Pink potassium map, placing younger strata on the northeast against older strata on the According to Schrader and Ross (1926) the deposits are traceable for 4,000

¡ Horizontal bedding.

¡

C Qls Cambrian–Early Ordovician alkalic magmatism in central Idaho: Impli-

53 ¡ D

53 Qg ª southwest. The northwest extent is poorly constrained by mapping but ¡ ¡ ft horizontally across Antimony Ridge and consist essentially of a single

Þ 49 ¡ X W feldspar phenocrysts are up to 4 cm in length and typically constitute 5 to

X W ¡

50 C ¡

¡

¡ cations for Rodinian rift tectonics: Geological Society of America Bulle-

² brecciation presumably related to faulting is present in the saddle where the quartz-stibnite vein, which is offset by small northwest-striking transverse Kgdp ¡ C 20 percent of the rock, but some exposures lack phenocrysts and are tonal- X W

70 X W C Strike and dip of foliation. Kgd B Qls C 78 Zqp 18 X W X W 45 Kgdp fault crosses Missouri Ridge. First recognized in the Stibnite quadrangle to tin, v. 122, no. 3/4, p. 430-453.

X W faults at several points. The vein strikes N. 40° E. and dips 75° SE. It is X W 7 itic. Phenocrysts form augen in well-foliated rocks. Abundant biotite is

X W

C Whiskey Creek fault

81 ª 36

C X W X W Oberbillig, J.J., Jr., 1980, Golden gate tungsten property, Valley County,

C 42X W Strike of vertical foliation. present as well-disseminated flakes up to 2 mm, comprising as much as 15 the east (Stewart and others, 2016) our tentative interpretation is that this is locally about 20 ft in maximum width and is opened at several points by N O Kgdsi Zqp? ªC

¡ ª ¬ a down-on-the-northeast normal fault. shallow workings, mostly by cuts and short tunnels on the west slope and Idaho, U.S.A.: Idaho Geological Survey Mineral Property File

¡ percent of the rock. Rare hornblende. Magnetite is a common constituent, ª ¡

37 65 43 CX W

¡ ª Silver 7 MPF-CH0771_039. Available at

C by a 75-ft adit at about 60 ft below the top of the ridge on the east slope.

N ¡ Strike and dip of bedding, strike variable. comprising as much as 2 percent of the rock, and is responsible for high C 52 42 35

¡ Qls Qg Cliff mine Zmss ª N 36 Schrader and Ross (1926) reported that the vein commonly showed from 6 https://idahogeomap.nkn.uidaho.edu/Data/MineDocs/CH0771_039.pdf

¡ C magnetic susceptibility values for this unit (see Table 1 and Symbols). Some

35 ¡ 40 8 Bearing and plunge of small fold axis. to 18 inches of clean, workable stibnite. At one locality there was a lens of (accessed 29 May 2020). C ¡ 61 35 of the leucocratic granite dikes also contain abundant magnetite and have JOHNSON CREEK SHEAR ZONE

Qaf ¡ C 1 Petersen, M.A., 1984, Geology of the Quartz Creek tungsten deposit, Yellow ²

² 75 Zmss? Qls ¡ the highest magnetic susceptibility values measured during this study (over stibnite 30 ft long with a maximum width of 5 ft. The main adit workings on C Kgdp

¡ 75 Bearing and plunge of crenulation lineation. The Johnson Creek shear zone strikes north-northeast and is vertical to very Pine, Idaho: M.S. thesis, Kent State University, Kent, Ohio, 94 p. ¡ 30 si units, compared to porphyritic granodiorite that typically has values of the east side contain a 2 to 3 ft wide vein of stibnite, and at 300 ft below the C 7 67 27 C 42 ¡ Kgdp Kgdp

¡ steeply east-dipping. The shear zone deforms muscovite-bearing 85 0.3 to 10 si units and biotite granodiorite with typical values below 0.1; mouth of the tunnel the vein is said to have exposed a shoot of stibnite 6 ft Schrader, F.C., and Ross, C.P., 1926, Antimony and quicksilver deposits in the

C ¡ 15 12 Bearing and plunge of mineral lineation.

¡ Cretaceous biotite granodiorite. Metasedimentary rocks are restricted to the Yellow Pine district, Idaho: U.S. Geological Survey Bulletin 780-D, p. Figure 3. Sigmoidal quartz grains near pencil tip, highlighted with pencil marks, in biotite C ¡ wide. Though the ore shoots are nearly all in the vein or fissure, some ore

7 Table 1). Unit is part of a northwest-trending belt of porphyritic granodiorite

¬

7 Qls ¡ ‰ Salt Creek fault ¡¡ eastern side of the shear zone in the Yellow Pine quadrangle. The shear 137-164. granodiorite two miles south of Yellow Pine in the northeast part of section 5, T 18N, R8E. ¡ 15 ¡¡ occurs also as replacement deposits in granodiorite. White (1942, 1945)

¡¡¡ ¡ that extends southeast to Stanley. Numerous workers have suggested that

¡ Headwall scarp.

80 C

¡ Combined with shallow south-plunging lineations, these features indicate a component of

7 zone contains a western high-temperature deformation zone marked by Smitherman, J.R., 1985, Geology of the Stibnite roof pendant, Valley County, ¡ noted that the Antimony Ridge mine produced about 1,000 tons of ore 75 Qls C the phenocrysts in this belt formed late in the origin of the rock (Lewis and 30 Qaf C 20 7 ² C Kgd Qg 30 elongate quartz and feldspar grains that locally define a strong foliation and Idaho: M.S. thesis, University of Idaho, 62 p. right-lateral deformation along the Johnson Creek shear zone.

54 C ˜ Vein. others, 1987 and references therein) and may be related to the injection or containing 45 percent of antimony. In contrast to the description of Schrad-

˜ lineation, and an eastern brittle zone characterized by heavily bleached Stewart, D.E., Stewart, E.D., Lewis, R.S., Weppner, K.N., and Isakson, V.H.,

7 20 18 er and Ross (1926) he indicated that the ore consisted largely of stibnite in C disaggregation of leucocratic dikes. Unruh and others (2008) determined a C ˜ Qaf 7 51 O Kgdo Kgd ˜ and altered granodiorite (unit Kgdsi). Within the high-temperature domain, 2016, Geologic map of the Stibnite quadrangle, Valley County, Idaho:

N Prospect pit. U-Pb zircon age of 93.2 ± 1.3 Ma from sample of hornblende-bearing well-defined north-striking quartz veins arranged in an en echelon system

˜ ‰

45 ¬ foliation orientation and fabric strength vary, but generally strengthen which strikes N. 50° E. The extent of the ore at depth is not known, but Idaho Geological Survey Geologic Map 51, scale 1:24,000. C granodiorite within this unit collected along the divide in the southeast part 50 70 30 7

C C60 C towards the east. Variation in fabric strength and orientation suggest strain Unruh, D.M., Lund, K., Kuntz, M.A., and Snee, L.W., 2008, Uranium-lead

~ 15 Adit. according to White (1945) a short tunnel near the west end of the vein

C of the map (see Symbols).

² 60 C was heterogeneous both across the shear zone and locally. Mining zircon ages and Sr, Nd, and Pb isotope geochemistry of selected plutonic N X W system, at an altitude of 6,850 ft, did not intersect the veins. Foliation Zlcf 75 15 Þ

X W 12

45 60 ÞÞ Breccia. prospects are abundant within the brittle, eastern part of the shear zone, rocks from western Idaho: U.S. Geological Survey Open-File Report

Qls ¶ 41 C Lineation ‰ 1 which is characterized by weak to intense silicification. 2008-1142, 36 p. 55 Kgdp METASEDIMENTARY ROCKS

¬ C C

X W 19DS16 !5 Geochronological sample location (Figure 2). White, D.E., 1942, Antimony Ridge mine, Yellow Pine district, Valley

‰ ¡‰¡¡¡¡‰ 40 5 C C SILVER CLIFF MINE (CH0777)

Pioneer Group Þ ¡¡¡ C 70 C ¬

51 ¡ 21 O_mq Middle quartzite (Cambrian to Ordovician)—Small, speculative exposure in County, Idaho: Unpublished Defense Minerals Administration report,

² Þ ¡ 70 Kgdp X W The shear zone is thought to have originally accommodated dextral

X W X W Location of magnetic susceptibility measurement (Table 1).

B ¡ X W

¡

Kgdsi Þ ¡ ¶7 45 Kgdo? Schrader and Ross (1926) describe the Silver Cliff mine, which here U.S. Geological Survey, Idaho Geological Survey Mineral Property File

¡ northeast corner of map. Where better exposed to the east, unit consists of ¡ Qaf 7 20 transpression. Kinematic indicators within the granodiorite, including 33 O

‰ 42 C B C 20

Þ C66 75 C ¬ C light-gray, medium- to fine-grained quartzite that contains approximately sigmoidal quartz grains, indicate a component of right-lateral deformation includes the Idaho Minerals Co. J.C.F.-Anaconda group of J.J. Oberbillig, 3 MPF-CH0773_003, 3 p., Available at https://idahogeomap.nkn.uida- 7 50 C Johnson Creek shear zone extent.

Þ B C Zmsm C miles south of Yellow Pine on the west side of Johnson Creek. The deposits ho.edu/Data/MineDocs/CH0773_003.pdf (accessed 29 May, 2020).

Emma Group C C 50 99 percent quartz and 1 percent potassium feldspar (Stewart and others, Qaf? B ¬ X W (Figure 3). Lineations plunge gently to moderately south but are generally Qls 75 44 55 66 30 47 C 68 C 46 X W consist largely of a north-south siliceous mineralized zone about 1,200 ft White, D.E., 1945, The Yellow Pine District, Valley County, Idaho: Unpub- ¡ ¬ 70 2016). Thickness there approximately 80 m (260 ft). The quartzite contains 20 to 30 degrees oblique to the vorticity normal section, as defined by the

45 ¡¡¡¡¡¡¡¡¡¡¡¡

C ¡ 500 Ma detrital zircons (Stewart and others, 2016) indicating a Cambrian or wide trending about parallel with Johnson Creek and rising from 300 to lished Defense Minerals Administration report, U.S. Geological Survey,

Qg !5 ¡ 30 Kgdo X W cylindrical best fit of poles to foliation (Fig. 4). This obliquity indicates the 7 ¡ C C 19DS27 C !5 œ ¡¡ Ordovician maximum depositional age. nearly 1,100 ft above it. The mineralized zone is composed chiefly of Idaho Geological Survey Mineral Property File MPF-CH0127_036, 6 p.,

Kgdo? X W MC92-35 shear zone contained a pure shear component of deformation in addition Qg? ¬ ¬ ¡ 36 56 DESCRIPTION OF MAP UNITS

52 ¡ altered granitic rock seamed with small quartz veins and stringers that Available at https://idahogeomap.nkn.uidaho.edu/Data/MineD-

¡ C 46 ¡ ¡

¡ Zmss C to right-lateral simple shear, and that the shear zone had an overall triclinic

C ¶ ¡ 66 ¡

Zmss 1 10 O_mm Middle marble (Cambrian to Ordovician)—Medium-gray, mostly massive contain sporadically distributed bodies and small veins or stringers of ocs/CH0773_003.pdf (accessed 29 May 2020).

B ¡ C symmetry. Pure shearing likely accommodated a horizontal shortening

44 ¡ 50 52 C In the following unit descriptions and later discussion of structure we use Vorticity axis N ¡ C marble in northeast corner of map. Medium to coarsely recrystallized with

¡ Kgdp stibnite a foot or more in maximum diameter. White (1945) reported a large Yonkee W.A., Dehler, C.D., Link, P.K., Balgord, E.A., Keeley, J.A., Hayes,

50 B C

46 Qls ¡ component of deformation. The timing of high-temperature deformation is

¡

C Kgd C 7 the metric system for sizes of mineral or clast constituents of rock units and

B ¡ 50 C faint millimeter-scale laminations. Locally contains gray anthophyllite as reserve of very low-grade gold ore in an extensive zone of brecciated and D.S., Wells, M.L., Fanning, C.M., and Johnston, S.M., 2014:

C ¡ 19

26 N ¡ 65 interpreted to have occurred between the Late Cretaceous and Eocene C for small-scale features of outcrops. Unit thickness and distance are listed

C Zlcf ‰ 44 1cm long “sticks” with square cross section, along with phlogopite, biotite, altered granodiorite. He noted that while several small lenses of stibnite Tectono-stratigraphic framework of Neoproterozoic to Cambrian strata,

Þ ¶ 36 12 C N based on the presence of ductile fabrics within Late Cretaceous C C 10

C 66 E Þ 30 C in both meters and feet (m/ft). Grain size classification of unconsolidated graphite, and diopside. Thickness is approximately 160 m (525 ft) to the have been found at the surface, none were seen in the main underground west-central U.S.: Protracted rifting, glaciation, and evolution of the Vorticity normal 60 ‰ 9 7 35 granodiorites and the lack of ductile fabrics in younger Eocene dikes to the

C C and consolidated sediment is based on the Wentworth scale (Lane, 1947).

Þ C east in the Stibnite roof pendant but may be greater in the Missouri C North American Cordilleran margin: Earth-Science Reviews, v. 136, p.

¬ 54 42 tunnel bearing west-northwest near Johnson Creek. He also noted that section Þ Zmsm B 55 north (Lund, 2004). The timing of lower temperature brittle deformation is 55 44 Kgdo? Intrusive rocks are classified according to IUGS nomenclature using Ridge-Sugar Mountain roof pendant on this map. On the basis of 59-95.

Qls _lq poorly constrained but at least some must have occurred after scheelite has been reported, but no tungsten ore bodies of any economic 42 43C normalized values of modal quartz (Q), alkali feldspar (A), and plagioclase

60 19ES05 !5 stratigraphic position and 500 Ma zircons in interlayered quartzite (unit significance had been found as of September 1944. According to Chris Dail 30 0

Qls Zmss ¬ C45 Zmsm 55 emplacement of the dikes in the Eocene.

15 ¬ Zmscs (P) on a ternary diagram (Le Bas and Streckeisen, 1991). O_mmq), we consider its age to be Cambrian or, less likely, Ordovician. C (written comm., 2019) several additional gold‐silver‐antimony‐tungsten

¬ 7 54

Zmss C 12 ´ Qg prospects west and southwest of the Silver Cliff adit were explored during 7 B C Zmsm O_mmq Quartzite within middle marble (Cambrian to Ordovician)—Light-gray, Benjamin Leonard’s June 29, 1957 field notes provide a description of the the 1970s through the 1990s by various operators (Kennecott, Cambior, 35 B 19DS28 42 40 Qls 57 medium- to coarse-grained quartzite present locally within the middle 65 ¡¡¡ ARTIFICIAL DEPOSITS eastern, silicified portion of the Johnson Creek shear zone northeast of C Kgd !523 ¡¡ 13 Meridian, Coeur, Pioneer, Amselco, and others). According to Bennett and

¡ k fault 30 22 Kgdo?

C ¡ marble unit in northeast corner of map. Thickness is approximately 25 m Yellow Pine: ¡ 17 7 ee Gillerman (1993) Cambior USA Inc. drilled 5 helicopter-supported core X W

¬ B Qls Zmss m Man-made ground (Holocene)—Small tailings pile at the Golden Gate mill on

Qal Qls ZlcfB 7C (80 ft). Just east of the quadrangle the quartzite contains abundant 500 Ma

80 ¬ 32 O holes, totaling about 2,200 ft, in September of 1992. These were located

¬ Qal Qls t Cr _lq the west side of Johnson Creek and disturbed ground at a quarry on the east detrital zircons (Stewart and others, 2016) consistent with a Cambrian or ACKNOWLEDGMENTS

50 7 _lq A fairly typical feature of the silicified zone in the Quartz Creek area is a along the silicified resistant rib 1,500 ft west of the Silver Cliff adit. They had

Kgd B¬ 45 Sal side of the town of Yellow Pine. Ordovician maximum depositional age (see zircon age discussion below). ¬ 60 15 Qls slight stain of brown limonite (from oxidized specks of pyrite?). In some trouble obtaining good samples with the portable Winkie drill that was The mapping presented here was funded in part by a grant from the Horse

Kgd 8

35 Zmss ´ _lq

‰ _lq C _lq Lower quartzite (Cambrian)—Light-gray, medium- to very coarse-grained places, the brown stain extends 100-200 ft beyond the limits of silicification. used but did intersect as much as 100 ft of 0.025 ounce-per-ton gold. In Heaven Syndicate, comprised of Matthew Mason, Timothy A. Young, Kgd 48 0 16 Kgd C SEDIMENTARY DEPOSITS C 42 B 65 Argillization is rather spotty. Though it is best seen close to mineralized addition, a rock-chip sampling program outlined a sizeable surface anoma- Stephen Stanley, and William H. Breen. Assistance by Clay Martin in 75 20 Qls X W quartzite and minor schist widely exposed in the southern part of the map. Zmsm Kgd 41 43 ly elongate along the Johnson Creek shear zone. B C Qls Qal Alluvium (Holocene)—Silt, sand, pebbles, and cobbles formed as channel or Moderately to poorly sorted. Most exposures contain little or no feldspar. zones (e.g., Kissinger Quartz Creek tungsten mine), in places it is present obtaining records from the U.S. Geological Survey Field Records Library is Figure 4. Equal area stereographic projection of poles to foliations (black circles) and lineations

C X W Þ 59 Qls C 68 near the margins of the silicified zones. Within the silicified zone, between greatly appreciated. !519DS26 B Zlcf Zmscs overbank deposits. May include terrace deposits along Tamarack Creek. Decimeter-scale bedding with diffuse bedding traces. Thin discontinuous (blue circles) from the western portion of the Johnson Creek shear zone. Poles to foliation define a C great circle distribution, which represents the vorticity normal section that results from the rotation 42 ¡ Clasts are rounded and locally show crude stratification and sorting. the East Fork and the north end of Red Mountain, there are at a given 49 beds of granule- to pebble-sized material fill scours in a B ¡ _lq 23 Qls of foliations during progressive simple shearing. Stretching lineations are generally oblique to the

26 ¡ latitude one or more quartz “veins”. Three are present in neighborhood of COPPER KING PROSPECT (CH0772)

20 Qls C X W northwest-southeast zone across the central part of the exposures. B ¡ ¡

´ 46 ¡

¡ N Qls Landslide deposits (Holocene and Pleistocene)—Silt to boulder-sized debris; vorticity normal section, inconsistent with plane strain simple shearing where lineations fall on the

¡

¡ B Oberbillig’s “north shore” claims. One is present at Red Mountain. I recall

¡ Thickness to the east in the Stibnite area is approximately 180 m (590 ft), ¡ ¡ 56

Zmss ¡

¡

¡ Kgdo? vorticity normal section. The obliquity suggests the shear zone had triclinic symmetry containing ¡ The Copper King prospect is reportedly located east of Johnson Creek

¡

¡ subangular to angular and poorly sorted. Formed by slope failure and ¡ ¡ _lq ¡ seeing just two at other places. These “veins” are essentially replacement

¡ B B 30 but here thickness is difficult to estimate. A highly speculative overturned

¡ characterized by hummocky surface visible in lidar imagery. Hachure southeast of the Golden Gate mine but was not visited during this study and components of both pure shear and simple shear. ¡ 44 8 bodies of quartz, with or without recognizable relics of slightly to almost Zmscs Kgd ¡ B fold shown on the map is thought to be the reason for the large area of 25 X W

¡ the exact location is uncertain. According to Schrader and Ross (1926) the ¡ denotes headwall. A landslide north of Ice Hole Campground in the south-

Zlcf Qls? 60 exposure. Alternatively, one or more unmapped thrust faults may have completely silicified granodiorite. In places the silicified rock is rather ¡ C Kgd 37 _lq west corner of map appears to have partly blocked Johnson Creek and Copper King vein is about 6 ft wide. It strikes about N 20° E and dips 80° E ¡ strongly sheared. Elsewhere, it is relatively massive. Everywhere, an

30 35 55 C thickened the section. Detrital zircon samples 19DS28 from Riordan Creek,

B 0 ¡ 24 25 10 Qls formed Deadhorse Rapids. This slide produced a low-gradient interval of and its course at the time was well-marked by a line of resistant outcrops ¡ C B envelope of rock veined by milky quartz or showing patchy silicification Lewis et al. (2012)

C C and 19DS16 from the south edge of the map contain abundant 1,740-1,840 Table 1. Magnetic susceptibility measurements of rocks in the Yellow Pine quadrangle. Values determined from

Zmsm C ¡ B 20 that formed a ridge which stood in places 10 ft or more abruptly above the

¡ C

¡ relatively well-sorted alluvium (Qal) upstream from the rapids. Spawning 7 ¡ 7 surrounds the intensely silicified main vein or veins. It is the outer limit of Stewart et al. (2013) hand specimens or rock faces as measured with a 1995 KT-9 Kappameter from Exploranium G.S. Ltd. and report-

58 7 Ma grains similar to Cambrian strata in the region. Zircon ages are Kgd ¡ Qg? adjacent surface. The vein is said to contain gold, silver, copper, and a little -3 C 35 20 40 gravels (redds) are common in this stretch of Johnson Creek. this silicified zone that I show on my map. In places the boundary between ed in SI units (x 10 ).

¡ 19DS16 discussed in more detail below. 45°15'

¡ Qls Qg? antimony (stibnite). In 1926 it was opened at several points on the south 65 20 ¡ C 7 16 !5 the silicified zone and the granodiorite is rather sharp, but mostly it is 7 C Qaf Alluvial-fan deposits (Holocene and Pleistocene)—Pebbles, cobbles, sand, Zlcf Lower calc-silicate and Fern marble, undivided (Neoproterozoic)—Medium to gradational, the silicification weakening outward and gradually slope of the ridge, chiefly by a 250-ft tunnel at an altitude of about 6,200 ft Map Unit Lithology La�tude (NAD27) Longitude (NAD27) Magne�c Suscep�bility and silt deposited near the mouth of streams where the gradient decreases. Big B dark gray-green calc-silicate rock, calc-silicate marble, and medium-to disappearing. in which the vein showed pyrite disseminated throughout the quartz Kgd muscovite-bio�te granodiorite 44.962647 -115.458134 0.07 Creek Kgd muscovite-bio�te granodiorite 44.962729 -115.453304 0.08 Clasts are rounded to subrounded and poorly to moderately sorted. dark-gray, coarsely re-crystallized marble. Quartz, biotite, calcite, and gangue. 115°30' Central and eastern Big Creek Kgd bio�te granodiorite 44.961628 -115.447166 0.09 Qg muscovite are common; calc-silicate minerals include epidote, tremolite, ! Kgd muscovite-bio�te granodiorite 44.962039 -115.451671 0.09 Glacial deposits (Pleistocene)—Unsorted to poorly sorted cobbles, gravel, The Red Mountain stockwork (IGS locality EC0912) is along strike of the Edwardsburg drainage SCALE 1:24,000 actinolite, anthophyllite, hornblende, and diopside. Marble is massive to Kgd bio�te granodiorite 44.960708 -115.436798 0.06 Base Map CreditBase Map Credit boulders, and sand deposited as lateral, ground, and end moraine. Lateral silicified part of the Johnson Creek shear zone, immediately north of this Kgd muscovite-bio�te granodiorite 44.958590 -115.435119 0.06 1 0.5 0 1 Field work conducted in 2019. ribbon laminated on a millimeter- to centimeter-scale. Dolomite is the NORTH SHORE PROSPECTS moraine deposits extend as much as 125 m (410 ft) above valley floor. map on the ridge east of Quartz Creek. Covering an area a little over 1 km2, Kgd weakly porphyri�c bio�te granodiorite 44.939596 -115.463702 0.02 Base digitallyTopographic scanned from base 24,000-scale modified from USGS digitally film separates,scanned MILE This geologic map was funded in part by a grant from the principle mineral. Thickness is uncertain, but approximately 100 to 300 m PARKS GAP Kgd weakly porphyri�c bio�te granodiorite 44.939005 -115.468702 0.09 1989. 1:24,000-scale paper map mapped by the U.S Forest Service FEET PEAK PROFILE Horse Heaven Syndicate. Locally includes outwash material in the lower elevations of some drainag- the stockwork is characterized by countless quartz veins and veinlets The Oberbillig “North Shore” prospects are not currently shown in IGS 7000 EDWARDSBURG (300 to 1,000 ft). Kgd weakly porphyri�c bio�te granodiorite 44.938639 -115.472022 0.05 (USFS) and the U.S. Geological Service (USGS). Edited and MN 1000 0 1000 2000 3000 4000 5000 6000 es. Includes outwash material on the valley floor of No Mans Creek. cutting extensively argillized granitic country rock (Leonard and Erdman, Shaded elevation from 10 m DEM. Digital cartography by Jonathan Sandquist. Mineral Property Files. Two short adits (35 ft, N42°E; 30 ft, S70°E) and Kgd weakly porphyri�c bio�te granodiorite 44.940663 -115.458679 0.07 published by the USGS. Yellow Pine Zqp 1983; Erdman and others, 1985; and Buehler and others, 1993). Much of associated cut located southeast of the mouth of Quartz Creek were visited ! Kgd feldspathic quartzite 44.932005 -115.454837 0.04 Topography by photogrammetric methods from aerial GN KILOMETER Technical review by Russ Di Fiori and Claudio Berti. Qgo Quartzite of Profile Creek (Neoproterozoic)—Medium-gray, medium- to Topography by photogrammetric methods from aerial 1 0.5 0 1 Glacial outwash deposits (Pleistocene)—Moderately to poorly sorted cobbles, the exposed stockwork is barren, but sparsely disseminated gold, pyrite, Kgd weakly porphyri�c bio�te granodiorite 44.932782 -115.455889 0.10 YELLOWPINE by Benjamin Leonard in June of 1957 (USGS Field Records Library photographs taken 1985. Field checked 1986. o o CATON Stibnite 0 10km LAKE STIBNITE coarse-grained feldspathic quartzite with feldspar content as much as 20 photographs taken 1964 and 1972. Field checked by the 1 06 13.2 Map version 2-4-2021. pebbles, boulders, sand, and silt deposited along Johnson Creek. Incised by arsenopyrite, pyrrhotite, and fluorite are reported. Plant specimens in and Kgd feldspathic quartzite 44.923167 -115.449557 0.08 Map edited 1989. percent. Plagioclase feldspar is in excess of potassium feldspar and some of notebook 3). Location shown on this map is only approximate. The adits Stibnite USGS in 1973. This map can be downloaded in PDF format from the modern stream. Abandoned braided stream channels and several levels ! Kgd quartzite 44.934088 -115.436165 0.16 Projection: Idaho coordinate system, central zone (Transverse Contour interval 80 feet near the stockwork contain anomalous concentrations of gold, were driven in silicified granodiorite that locally exhibits argillic alteration. Transverse Mercator projection. 1927 North American Datum. www.idahogeology.org of fluvial terraces are visible in lidar imagery. the feldspar is interstitial or in veinlets, indicating a secondary origin. Centi- Kgd calc-silicate quartzite 44.931563 -115.426861 0.36 Mercator). 1927 North American Datum. molybdenum, tungsten, and tin. According to Buehler and others (1993), a Rocks were stained yellow, orange, and red. The second adit intersected a Kgd bio�te-muscovite schist 44.931947 -115.425461 0.38 LOG meter- to decimeter-scale bedding with planar cross laminations and rare 115°00' PEAK CHILCOOT BIG CHIEF 10,000-foot grid ticks: State Plane Coordinate System, Idaho UTM Grid and CREEK IDAHO Kgd foliated porphyri�c granodiorite 44.923739 -115.417441 7.2 10,000-foot grid ticks based on Idaho coordinate system, MOUNTAIN graded beds. Contains millimeter-scale biotite-rich interbeds and centime- 1,370-ft-long adit was run from the valley floor east toward the mineralized N30°E, 45°SE shear zone. West Zone. 2020 Magnetic North Ts Sediments (Tertiary)—Cobble gravel occurring on perched low gradient slopes central zone. zone in 1962 and 1963. No ore-grade mineralization was encountered in Stewart et al. (2016) Kgdo bio�te-rich porphyri�c granodiorite 44.921871 -115.416516 9.3 Declination at Center of Map in the northern part of the map. Found between 60 and 105 m (200 to 350 ter-scale granule beds. Amphibolite sills present locally. Minimum 1000-meter grid ticks: Universal Transverse Mercator, zone 11. The IGS does not guarantee this map or digital data to be ADJOINING QUADRANGLES QUADRANGLE LOCATION the adit and it was subsequently abandoned. Between 1975 and 1988, four Kgdo leucocra�c granite 44.923486 -115.409918 3.1 1000-meter Universal Transverse Mercator grid ticks, zone 11. free of errors nor assume liability for interpretations made ft) above modern stream levels. thickness is approximately 500 m (1640 ft); base is not exposed. Lund Burntlog Creek Kgdo foliated porphyri�c granodiorite 44.925071 -115.417457 7.1 Shaded relief from 10 m DEM and 0.3 m LiDAR DEM. from this map or digital data, or decisions based thereon. (2004) assigned this unit to the Gunsight Formation of the Mesoproterozoic holes, ranging from 117 to 580 ft, were drilled on the property. Placer EMMA GROUP (CH0778) area 44°45' Kgdo leucocra�c granite 44.924314 -115.404167 9.3 LiDAR DEM courtesy of Midas Gold Idaho, Inc. age Lemhi Group. An abundance of 1,090-1,150 Ma detrital zircons, and a Dome U.S., Inc., began a 24-hole drilling program in 1988 that lasted until Kgdp porphyri�c granodiorite 44.924314 -115.404167 8.3 1991 (Buehler and others, 1993; Bennett and Gillerman, 1992). Placer The Emma group consists of two short adits and a series of small cuts north- Kgdp bio�te-rich porphyri�c granodiorite 44.923915 -115.398625 5.3 INTRUSIVE ROCKS few as young as 685 Ma, indicates that these rocks are more likely Neopro- Kgdp bio�te-rich porphyri�c granodiorite 44.923738 -115.396531 11 Dome identified a low-grade gold resource of about 7.7 tonnes of gold in 9 east of Riordan Creek. Two Defense Minerals Exploration Administration Landmark terozoic in age. Possibly correlative to the quartzite and schist unit mapped ! Kgdp bio�te-rich porphyri�c granodiorite 44.923086 -115.391809 8.4 Ta Andesite dikes (Eocene)—Medium- to dark-gray, very fine grained to aphyric to the east in the Stibnite area by Stewart and others (2016). Zircon ages are million tonnes of mineralized rock, with an average grade of 0.9 ppm gold (DMEA) loan applications were made in the 1950s for claims in this area, Kgdp bio�te-rich porphyri�c granodiorite 44.924253 -115.388949 3.1 andesite with few or no phenocrysts. Euhedral plagioclase present at some (Bart Stryhas, personal commun., 1992, in Bookstrom and others, 1998). details of which are available in Frank (2016). Information from DMEA Kgdp leucocra�c granite 44.924253 -115.388949 3.6 discussed in more detail below. Kgdp bio�te-rich porphyri�c granodiorite 44.925232 -115.386368 4.9 South of Yellow Pine the silicified zone contains the Golden Gate mine and Dockets 3466 and 4455 indicates that scheelite float is found in the area, Stewart et al. (2017) localities. Kgdp bio�te-rich granodiorite 44.927899 -115.395859 2.4 Zmss Schist of Moores Station Formation (Neoproterozoic)—Schist, quartzite, and the Silver Cliff mine discussed below. but that many of the larger “exposures” of calc-silicate rock are not in Kgdp bio�te-rich porphyri�c granodiorite 44.930232 -115.395578 5.9 Tr Rhyolite dikes (Eocene)—Light- to medium-gray rhyolite with less than 15 minor marble and calc-silicate rocks. Schist is medium to dark gray and place. Lidar imagery of the area indicates that the prospects are in and near Figure 1. Location map showing the Yellow Pine quadrangle and areas with recently Kgdp bio�te-rich porphyri�c granodiorite 44.931123 -115.395358 16 percent phenocrysts of quartz (as much as 2 mm in length and typically consists of as much as 40 percent small (<1 mm) biotite and muscovite the head of a landslide. published Idaho Geological Survey geologic maps. Kgdp bio�te-rich porphyri�c granodiorite 44.932547 -115.395643 1.4 partially resorbed), potassium feldspar (as much as 2 mm in length), Kgdp bio�te schist 44.948584 -115.396092 0.41 grains in various proportions and 60 percent or greater fine-grained quartz Kgdp muscovite-bio�te schist 44.946057 -115.388903 2.1 plagioclase, and minor biotite. Phenocrysts are set in an aphanitic matrix of and plagioclase in various proportions. Sillimanite is common and garnet is Kgdp muscovite-bio�te schist 44.944738 -115.381589 0.51 quartz and feldspar. Locally aphyric. Kgdp bio�te schist 44.941934 -115.375191 0.72 Kgdp muscovite-bio�te schist 44.938873 -115.376298 0.02 Kgdp muscovite-bio�te schist 44.936595 -115.377282 1.8 Kgdp bio�te-rich porphyri�c granodiorite 44.926658 -115.382740 3.3 A A´ Kgdp leucocra�c granite 44.928916 -115.379910 0.47 8000 Zmss 8000 Qls Antimony Kgdp hornblende-bio�te granodiorite 44.931781 -115.376594 3.5 Zqp Kgdp bio�te-hornblende quartz diorite 44.909841 -115.377329 1.2 Ridge Kgdp leucocra�c granite 44.907724 -115.377963 0.09 Bishop B B´ Johnson Creek shear zone Qls Zmss Kgdp bio�te-rich granodiorite 44.906369 -115.385996 0.28 7000 No Mans Creek 7000 8000 8000 Kgdp bio�te granodiorite 44.903852 -115.388240 0.17 Whiskey Creek fault No Mans Creek Kgdp bio�te-rich granodiorite 44.902296 -115.389372 0.21 Johnson Creek _lq bio�te-rich granodiorite 44.901390 -115.392761 0.28 Creek Qls Zmss bio�te-rich granodiorite 44.903283 -115.376797 1.2 Whiskey Creek 6000 6000 7000 Riordan Qls East Fork of 7000 Zmss fine-grained bio�te granodiorite 44.885804 -115.378980 0.11 _lq fault South Fork Zmss bio�te schist 44.884765 -115.383351 0.39 Ta Qg Zlcf Creek Zlcf Kgd Salmon River Zmss bio�te schist 44.882514 -115.386327 0.45 Zmss quartzite 44.879903 -115.402991 0.05 Qgo Foliation Qg _lq Zmss bio�te-quartz schist 44.890065 -115.396585 0.62 5000 Zqp 5000 6000 Zqp 6000 Zmss weakly porphyri�c bio�te granodiorite 44.909428 -115.432989 0.04 Whiskey Creek fault Zmss weakly porphyri�c bio�te granodiorite 44.906222 -115.432149 0.50 Kgdsi Kgd Zlcf Zmss Zmss Zmss leucocra�c granite 44.948584 -115.396092 0.03 Zqp Qal 4000 Mylonitic 4000 5000 Kgd 5000 Zmss leucocra�c granite 44.946057 -115.388903 0.02 _lq Kgd Kgdp Zmss bio�te granodiorite 44.958590 -115.435119 0.06 foliation Zlcf Zqp Zmss leucocra�c granite 44.944738 -115.381589 0.05 Zmss leucocra�c granite 44.941934 -115.375191 0.03 Zmss Zmss leucocra�c granite 44.923086 -115.391809 17 3000 3000 4000 Zqp 4000 Zmss Zqp Zqp leucocra�c granite 44.923915 -115.398625 36 Kgdo Zqp leucocra�c granite 44.906222 -115.432149 0.06 Kgd Zlcf Kgd Foliation Mylonitic Zqp weakly porphyri�c bio�te granodiorite 44.937887 -115.458036 0.06 foliation Kgdo Zqp weakly porphyri�c bio�te granodiorite 44.935762 -115.457645 0.05 2000 2000 3000 Zmss 3000 Zqp bio�te quartzite 44.932698 -115.419947 0.39

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