(
PROGRESS REPORT- BETTY O'NEAL/ST. GEORGE METALS' ·PROPERTIES LANDER COUNTY, NEVADA
DECEMBER .7, 1992
Prepared by:
Arthur R. Leger Cyprus Metals Company- Sparks, Nevada
Prepared for:
J.A. Matlock Cyprus Metals Company 1320 Freeport Blvd. Sparks, Nevada ( CONTENTS _,
PAGE
SUMMARY AND RECOMMENDATIONS ...... !
INTRODUCTION ...... 3
Location and accessibility ...... 3
Climate, topography, and vegetation ...... 3
Mining history and previous exploration activities ...... 3
l.and ...... ····· ...... 11
Exploration Methods ...... 12
GENERAL GEOLOGY ...... 12
Sedimentary rocks ...... 12
Paleozoic rocks ...... 12
Siliceous - volcanic (western) assemblage.·: ...... ·: ...... 12
(Ordovician System- Valmy Formation) ...... :...... 12
Overlap assemblage ...... 15
(Pennsylvanian and Permian Systems- Antler Sequence) ...... 15
Havallah sequence ...... ·: ...... 15
(Pennsylvanian and Permian Systems - Havallah Formation) ...... 16
Mesozoic strata ...... 16
Triassic System - Panther Canyon Member of the Augusta Mountains Formation ..... 16
Igneous rocks ...... 16
II Contents, Cont. ( PAGE
Intrusive rocks ...... 17
Extrusive units ...... 17
STRUCTURAL SUMMARY ...... 17
Regional structure ...... 17
Paleozoic deformation ...... 17
Antler orogeny - Roberts Mountain thrust...... 17
Sonoma orogeny - Golconda thrust...... 19
Post- Upper Paleozoic tilting ...... 19
Mesozoic folding ...... 19
Tertiary faulting ...... 20 ( PREVIOUS EXPLORATION RESULTS ...... 20
Noranda ...... 20
Silver - lead - zinc veins ...... 21
Gold ...... 21
St. George/Reynolds Metals ...... 22
Cyprus activities ...... 22
Geology ...... 22
Local structure ...... 23
Mineralization ...... 24
Alteration ...... 24
Geochemistry ...... 25 III Contents, Cont. ( PAGE
Rock-chip ...... 25
Soil...... 25
Geophysics ...... · ...... 25
Magnetics ...... 25
IF/Resistivity ...... 27
Lineaments ...... 29
RECOMMENDATIONS ...... 29
REFERENCES CITED ...... 31
IV
'I CONTENTS
ILLUSTRATIONS (Plates are in packet)
PLATE I. Land status - Lewis District: . Lander County, Nevada (1 II= 1000')
II. Betty O'Neal Mine- composite of mine workings (1 II =200')
III. Land holdings- Section 22, T30N, R45E: Betty O'Neal/Lower Whisky Canyon area (1 II =200')
IV. Geologic map of St. George property: Lander County, Nevada (1 II= 1000')
v. Geologic map of Betty O'Neal/Lower Whisky Canyon area (1 II =200')
VI. Rock-chip geochem map- Betty O'Neal/Lower Whisky Canyon: ( Lander County, Nevada (1 ~~-200')
VII. Gold soil geochem map- Lower Whisky Canyon (1 II =200')
VIII. Silver soil geochem map- Lower Whisky Canyon (1 II =2Q0')
IX. Arsenic soil geochem map - Lower Whisky Canyon (1 II =200')
X. Antimony soil geochem map- Lower Whisky Canyon (1 II =200')
XI. Zinc soil geochem map - Lower Whisky Canyon (1" =200')
XII. Aeromagnetic, ground magnetic, IF/Resistivity interpretation map - St. George/Betty O'Neal properties: Lander County, Nevada (1 II= 1000')
XIII. Aeromagnetic, ground magnetic, IF/Resistivity and total lineament map - Betty O'Neal/Lower Whisky Canyon area: Lander County, Nevada (1 II =200')
v
.i ( PAGE
Figure 1. Location of Betty O'Neal and St. George Metals' Properties ...... 4
2. Photograph of Lewis District - looking southeast ...... 5
3. Fisher gold project - Lucky Rock/Red Cap area ...... 6
4. Fisher gold project- Whisky Canyon area ...... 6
5. Lewis District - property map ...... 7
6. Fisher gold project - claim map ...... 10
7. Stratigraphic column - Betty O'Neal area ...... 13
8. Structural relationship of the Paleozoic rocks of North-Central Nevada ...... 14
9. Simplified geologic map of north-central Nevada ...... 18
10. Location map for Cyprus rock-chip samples ...... 26
11. Section showing proposed gold targets I and II Betty O'Neal- Lower Whisky Canron ...... 30
VI
.• . APPENDICES (
PAGE
A. Mineralized drill intercepts: . Noranda- Betty O'Neal Project- 1980-81...... 33
B. St. George Metals, Inc. drilling summary, Lucky Rock - Red Cap area ...... 36
C. Cyprus rock-chip geochemical data: Betty O'Neal area- Sections 22 & 23, T30N, R45E ...... 45
VII ( SUMMARY AND RECOMMENDATIONS
The Betty O'Neal/St. George Metals' land holdings are located in the Lewis Mining District, on the west side of the Shoshone Range, 14 miles south of the town of Battle Mountain, Nevada.
Silver was discovered in the Lewis District in 1870, and the Betty O'Neal Mine started producing silver in 1880. Early production records are unavailable but from 1922 through 1928, 170,388 tons of ore were milled, averaging 24 oz./ton silver. The mine ceased production in 1928.
Past exploration activities, in the search for gold and silver, include surface and underground mapping, geophysical surveys, rock-chip and soil grochemical surveys, and drilling. These activities were performed by Noranda (1980-81), St. George Metals, Inc. (1986-88), and Reynolds Metals Company (1988-1991). Gold mineralization was found to be hosted by the Ordovician age Valmy Formation and generally restricted to narrow, north-northwest trending quartz veins. Two areas within the range were found to contain a drill indicated "geologic resource" of approximately 1,000,000 tons grading 0.026 oz. Au/ton and 445,000 tons grading 0.036 oz. Au/ton at a 0.010 oz. Au/ton cut-off grade.
Cyprus personnel (ARL and DAD) became interested in the area because of the recorded precious metal occurrences and recorded Antler sequence rocks cropping out adjacent to pediment gravels.
Geologic mapping and rock-chip/soil geochemical data have revealed the presence of mineralized Havallah sequence rocks croping out in the pediment west of outcropping Antler units. In addition, a N40° W structure (Lower Whisky Canyon Fault) appears to be a mineralizing feeder and trends into the Havallah rocks. It is proposed that the gold and associated trace element mineralization noted in the outcropping Havallah units, may represent leakage from a buried, Antler sequence hosted gold deposit.
Aeromagnetic and IP/Resistivity data have defined a major northwest-southeast trending structure, located off the range front, which is on trend with the Betty O'Neal Mine. In addition, the IP/Resistivity information suggests a complex response northwest of the Betty O'Neal Mine. Frank Fritz, consulting geophysicist, considers both features to be promising exploration targets. Summary and Recommendations, Cont.
It is therefore suggested that at least two areas exhibit characteristics similar to other producing gold mines (Cove-McCoy, Chimney Creek, Lone Tree). A "major" gold deposit could be hosted by Havallah/ Antler rocks near the intersection of the Lower Whisky Canyon Fault and a postulated range bounding northeast-southwest _trending structure. The same situation is believed to be developed along the Betty O'Neal Mine trend.
It is recommended that: (1) the Betty O'Neal land block be obtained; (2) the Red Cap claims be leased from St. George Metals; (3) a geophysical survey be considered to accurately define structural intersections; and (4) a major drill program be planned.
2
... ~ .,. ~··· ·..
-~ ~ . ·. , .. :~ . ·,. ~ INTRODUCTION
LOCATION AND ACCESSIBILITY
The Betty O'Neal Mine land block and adjoining St. George Metals' properties are in the Lewis Mining District, on the west side of the Shoshone Range, 14 miles south of the town of Battle Mountain, Nevada. Access to the area is by a paved and improved dirt road (old highway 8A) which leads south from the town. After nine miles, an improved dirt road heads southeast towards the range front and mouth of Lewis Canyon (Fig. 1).
CLIMATE, TOPOGRAPHY, AND VEGETATION
The climate is characterized by dry, hot summers and moderately cold winters. Several feet of snow and seasonal rains may limit access at times in the winter and spring.
The property is within the Basin and Range topographic province which consists of steep mountain ranges, trending generally north and south, separated by valleys several miles in width. The Reese River Valley, northwest of the property, is at 4,650 feet and the Shoshone Range on the east rises to 9,680 feet elevation at Mt. Lewis. The property itself has 1,370 feet of relief with the highest elevation at 6, 745 feet in the area near Rocky Canyon.
Vegetation consists of native grasses and sagebrush.
Surface water is scarce. It can be found in some of the rriajor canyons such as Rocky Canyon, but it may not be present during dry summers. · '
MINING HISTORY AND PREVIOUS EXPLORATION ACTIVITIES
This section is condensed from previous works, especially Olander (1981), Broderick (1988), and Robinson (1989). Almost all of the mining and exploration activities within the studied area has been done either in Lewis Canyon, at the Betty O'Neal Mine, or within the range on the Lucky Rock/Red Cap, and Whisky Canyon claims (Plate I and Figs. 2,3,4,& 5). Very little exploration work has been done on the pediment area west of the range front.
The first discovery of silver in the Lewis District was made during the 1870's and the first mines to go into production were in Lewis Canyon. In 1880 surface work started at the Betty O'Neal Mine (on the Betty Vein) and by 1882 the vein was being worked underground from several levels (Plate II). A boiler explosion and subsequent difficulties caused the mine to close.
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1 2 3 56 7 8
Figure 2. (from St. George Minerals, Inc. 1988) PHOTOGRAPH OF THE LEWIS DISTRICT LOOKING SOUTHEAST
This photograph was taken in January 1988 and shows the relation ships of the ST. GEORGE MINERALS, INC. properties to one another as well. as giving an overall setting to the district. Each of: the identified items are explained as follows:
1. DEAN MINE - the Dean Mine is located along the ridge of the Shoshone Mountains near a low·pass at an elevation of 7650 feet. 2. LEWIS CANYON - Lewis canyon was the site of several stamp mills which were active during the 1860's to 1900's to process ore from mines located along its course. 3. BETTY O'NEAL MINE - This is an area where extremely rich silver deposits were exploited. 4. BETTY O'NEAL MILL - This is the site of the milling facilities constructed in the 1920's to process the ore from the Betty O'Neal Mine. 5. WHISKY CANYON - This is the eastern most portion of the FISHER GOLD PROJECT. 6. MOUNT LEWIS - This is the highest point in the Shoshone Range and has a radar facility used to monitor airliner traffic in this portion of the country, elevation is 9600 feet. 7. LUCKY ROCK/RED CAP AREA- This area represents the eastern most portion of the FISHER GOLD PROJECT. 8. ROCKY CANYON - Rocky Canyon is a major drainage which terminates the property area to the southwest. (
Figure 3. (from St. George Minerals, Inc. 1988) I FISHER GOLD PROJECT - LUCKY ROCK I RED CAP AREA This photograph shows the extensive drill roads constructed by ST. GEORGE MINERALS, during 1987, all of these roads were sampled on ten foot intervals before drilling began.
Figure 4. (from St. George Minerals, Inc. 1988) FISHER GOLD PROJECT - WHISKY CANYON AREA This photograph shows the drill roads in Whisky Canyon (most constructed by Noranda Explorations in 1980) as well as the Record Claim area on the Betty 0' Neal property, with the Betty O'Neal Mill in the foreground. ( • • 0 •• 0 ••• 0 •
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2~ • 30
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Figure 5
S T. G E 0 R G E M ETA L S, I N C.
SCALE IN WILES LEWIS DISTRICT
o/z 0 PROPERTY MAP
. Laoder , County, Nevada 7 ( By 1910, L.W. Getchell had purchased the mine and unsuccessful attempts were made to re open the workings. Getchell died in 1918, and his son, Noble H. Getchell, took control of the mine in 1920. After organizing a company and selling shares to generate capital, underground development work commenced. A mill was constructed, and production was resumed in 1922. From 1922 through 1928, 170,388 tons of ore were milled, averaging 24 oz./ton silver, yielding 3,566,065 ounces of silver. Most of this production was from the Estella vein, the largest producer in the district.
By the end of 1928, most of the known ore had been removed. The mill closed in January 1929, and the mine was never put into full production again. This was due to: (1) lack of sufficient funds to spend on exploration and development, (2) the price of silver dropped below what was needed to operate the mine profitably, and (3) unsuccessful attempts to discover more ore at depth.
From 1929 to 1935, the mine was leased to small operators. In 1935, Getchell attempted tore open the mine, but bad ground, low ore grades, and loss of financial support caused this venture to be abandoned. The mine was again leased and worked intermittently from 1935 to 1954.
A geophysical program, which included S.P. surveys and drill holes in anomalous areas, was done by Stephenson (1956). The results of this program were inconclusive due to the nature of the rocks (graphite and sulfide content of the shales made interpretation of the results difficult) and post-ore faulting.
Ownership of the mine passed into the hands of the Battle Mountain State Bank Mortgage Corporation in 1954. The claims were leased to Mr. C.T. McNeil in 1964, who operated the property as the Betty O ~ Neal Silver Mine, Inc., which became Betty O'Neal Silver, Inc. in 1965. .
From 1965 through 1967, several consulting geologists and mining engineers worked at the mine, both on the surface and underground (Lawrence, 1965; Weyler, 1967; Payne, 1967). In 1965, a contract from the U.S. Government's Office of Mineral Exploration (OME) was approved by the mine owners and the government. Work was to be done in two stages: first, diamond drilling from the surface, and second, follow-up work in specific areas indicated by the drilling. Detailed surface and underground maps were prepared to assist in the interpretation of the drilling data. Several veins were intersected in the drill holes. Some were projections down dip and along strike of known veins, but a few were previously unknown.
In 1969, all interest in the mine held by Betty 0' Neal Silver, Inc., was assigned to the Condor Corporation. During the late 1960's and on through the 1970's, several more reports were prepared on the potential of the Betty O'Neal Mine (Tingley, 1969; Mineral Industries Engineers, Inc., 1975; Pierce, 1976).
8 ( In 1974, Cascade-Betty O'Neal Corporation acquired a fifty-two percent interest in the claims, and in 1977, Cascade Minerals Corporation leased 100 percent of the right to the property. Late in 1980, Cascade Minerals Corporation became Cascade Resources Joint Venture.
In early 1980, Cascade Minerals Corporation contacted Norand~ __E~plorat~f!,Jnc., and in July 1980, an__exploration agreement to explore for gold and silver was signed by the two companies. On March 20, 1981, Noranda decided not to continue with the option for the 1981 exploration program as set forth in the exploration agreement.
St. George Metals, Inc., initially became involved in the area in 1986, and Barringer Geoservices, under contract to St. George, completed preliminary geologic mapping, rock sampling, and soil geochemistry in the eastern part of the property (Whisky Canyon, Betty O'Neal South, and Dean- Plate I).
In !.2.8.7~-St. George continued exploration activities in the Whisky Canyon, Lucky Rock, and ' I ' p (/:f'l_v; - Red Cap areas (Plate I, Figs. 2,3,& 4). Three dia~_Q _ an_d_nine__reyerse _circulation holes were drilled as well as extensive road building, road c ut rock-chip sampling, soil geochemistry, and geologic mapping.
In February 1988, the Bureau of Land Management (BLM), accepted and approved a Plan of Operations (N66-88-02P) submitted by St. George Metals for continued exploration of their Fisher gold (Lucky Rock and Red Cap) area (Fig.3) and adjacent holdings.
In October 1988, a joint exploration venture was formed between St. George, as operator, and Reynolds Metals Company. The relationship terminated January 25, 1991. Exploration .. activities consisted of surface geologic mapping at a sc3.le of 1: 1200; undetground geologic mapping at a scale of 1:240; detailed soil sampling; ex~_ns!Ye road_cut chip chel!lnel sampling;__ ~ and reverse _circulation/~gJhe majority of work was confined to the Lucky Rock and Red Cap claims (Plate I, Fig.6).
9
·-- . - ·' NORTH CAP . ( NORTH NORTH NORTH No. I CAf. ·cp._P_ . CAP · No. 4 No. 3 No. 2
2 2 Z3
I,006,0CO /'E
REO .CAP EXTENSION No. I 3
REO REO CAP CAP No. No. 3 I I
we Nq • . 3
WC No. I
27 26
ST. GEORGE MINERALS, INC.
i ·Figure 6
FISHER - ~OLD PROJECT :CLAIM MAP _ . !_LEWIS DISTRICL Lander .- ca·u·nfy; Nevada
SCA.L E IH FEET 1000 100 0 1000
10 · Jon P •.• B. to de rl.c;_k_ ,Consul tlng Gaol ogl s t March I 988 ( LAND
Plate I shows most of the owners of the properties in the Lewis Mining District. The Betty O'Neal and St. George land holdings are highlighted. Exploration activities to date indicate that Section 22, T30N, R45E is the main area of interest (Plate Ill).
The Betty O'Neal land block must be obtained in order to continue our .exploration program. The Red Cap claims should also be leased, but targets could be tested on the Betty O'Neal claims if a lease cannot be negotiated with St. George.
The following is Hans Bihr's summary of the agreement which gives St. George Metals control of the Red Cap and Whisky Canyon (y{C) claim groups:
Type of Agreement: Sales Agreement
Effective Date: March 20, 1986
Parties: Fisher et al and St. George Metals, Inc.
Property: Red Cap and WC Claim Groups
Purchase Price: $750,000 To date $285,000 of the purchase price should have already been paid. F~sher et al will no longer have an interest in the claims when pu,rchase price is paid 'in full.
Payment: $60,000 per year
Production Royalty: 3% gross or $60,000 per year, whichever is higher. If a production royalty is paid, the amounts paid will be credited against the purchase price.
Area of Interest: One mile from perimeter of claims. Any claims located by either party would be included in the agreement.
Assignment: Can be assigned with written consent of Fisher et al. Twenty-five percent of the proceeds received by St. George as consideration for the assignment would be payable to Fisher et al, however, such payment will be credited against the purchase price. Assignee must agree in writing to be bound by the terms of the agreement.
Termination: Must give written notice. 11 ------
( EXPLORATION METHODS
The St. George property covers approximately five~ square miles. Geologic data was plotted on air photos (scale 1" =2000') and topographic maps (scales 1" = 1000' and 1" =200'- Plates IV and V). David Blake, consulting geologist, aided in the 1" = 1000' scale geologic mapping and A.R. Leger developed the 1" =200' geologic m~p. In addition, Darrel Dean, in cooperation with Blake, took responsibility for evaluating the southern one-half of the St. George holdings (sees. 28 and 32 - plate IV).
Rock-chips were collected from shear zones; from rocks exhibiting iron staining, silica flooding, and decalcification; from areas of quartz and calcite veining; and from altered igneous rocks. All samples were analyzed for gold-silver and associated trace elements (arsenic, antimony, mercury, lead, zinc, copper, and molybdenum).
GENERAL GEOLOGY
SEDIMENTARY ROCKS
The sedimentary rocks of Paleozoic and Mesozoic age in the Betty O'Neal region include the following representations: Paleozoic age siliceous - volcanic (western) assemblage - Valmy Formation; the overlap assemblage - Antler sequence; siliceous-volcanic province - Havallah sequence; and Mesozoic age Panther Canyon Member of the Augusta Mountains Formation (Figs. 7 & 8). ·
PALEOZOIC ROCKS: Paleozoic rocks consist of terrigenous conglomerates, shallow water marine carbonates, and deep water siliciclastic and pelagic units.
Siliceous-Volcanic (Western) Assemblage: The siliceous-volcanic (western) assemblage is represented in the Betty O'Neal/Lower Whisky Canyon area by one formation, the Valmy.
(Ordovician Systetn - Valmy Formation): The Valmy Formation was originally deposited far to the west and brought to its present position in the upper plate of the Roberts Mountain thrust fault (Fig. 8).
Within the St. George property, the Valmy Formation comprises most of the bedrock exposed (Plate IV). No detailed mapping was attempted by the writer, but Blake (1992, p.4) recognized seven mappable units within the formation. These are chert, quartzite, greenstone, shale, and minor amounts of limestone and sandstone.
12 ~ Alluvium
C~ETANO TUFF ( T vu I T d Tqp _.,...- ·· ---- •vu Vole en•-: rocks undi fferer.l;ated Tuffs and tv'· F .. ... PANTHER breccias j ONVO>I conqlomerole. P"lpcl ' Td D•a~ase " H.1VlLLAH SEOUENCE ' , _"" Tqr Ouartz porphyntoc rocks !,loslly daco!ic
... ""' )·• Lothic breccia. showing ci;> ~ A: ;TLER PEAK "- Ropcm C.ongloMera!e. maroon j ?f?hs J HA " /ALU~.H SECUI-tCE Pf?hs· Siltstone. catcore:>us L cn .• oo:cled slit slcne, .,.,.,,.~,. rhe~r . -.or • J ~•(· "' e C v ·~o GOL'..: OND !Jo TH?. '...iST Lt'!erl. orgillile O·, co ~ ANTLER PEul\ Lf~.IESTONE ~ BATTLC: FORMATION z Ouorlzile. moH1ve. Ovq 0 _,______------I- z ~ VALMY FORMATION ~ ::< a: u 0 Ovchs l Ov c; > "- Co •c or~ou s -.;,:ts!:>ne . SO :'IO S!one. mtnor Cilerl. 0 0 o .. a: >- 0 ::< O·JC Cheri _J !:>ae rie . T OCI < Ovq· Ouarl zit e I Sor.ds! one > z Ovg Greens:one limestone 0 0 0:: 0 Ovsa Sitlstor.e end cr~iHitc . locally c~ICorecus Ovco Cher: and or<;tlii:'! Gre~ns t on~ flows Ovg Ovchs Cherty silts tone Ovcs Chert and siltstone Cheri. minor cherty silt stone. Qv,-s Ovsca Sond'>lone. colcoreo ... s NOTE Subscript on some rljCK :ypc. Ovcz denotes distinctly :ncppoble unit. no chronologie order implied Fi gu r e 7 ST. GEORGE METALS INC. ' PROJECT : BETTY 0 ' NEAL L o c : :...E WI S DiSTRICT is T : NV !c T v : L ANDER STRATIGRAPHIC COLUM N GEOLOGIC SYMBOLS 13 OVERLAP ASSEMBLAGE !S/1/csous and !Conglomt~rat• and Carbonats Volcanic Provlnc9l Provine• (Autochthonou5)l ( Golconda Thrust (Sonoma Orogeny)- -- PERMIAN Antlsr Ssqusnc9 of Robsrts (1964) PENNSYLVANIAN ANGULAR UNCONFORMITY MISSISSIPPIAN (Antler Orogeny) Roberts Mtns. Thrust Carbona (Ea5ftun) A 559mb/a Slllc90U5 and Volcanic (Wsstsrn A 55Bmblag9) DEVONIAN SILURIAN Transitional A S5flmblagt~ ORDOVICIAN ,_,,r,.ufochonous) CAMBRIAN PRECAMBRIAN Osgood Mtns. and Edna Mountain Figure s - Structural relationship of the Paleozoic rocks of North-Central Nevada (Hatched area represents a period of non-deposition. Modified from Madrid, 1987) 14 ( Overlap Assemblage: Roberts (1949, p.1917) proposed the name Antler orogeny for the tectonic event that ended the geosynclinal cycle of sedimentation that had persisted in central and western Nevada from Cambrian to Late Devonian time and ushered in a new cycle. Coarse clastic rocks derived from the orogenic belt were deposited to the east and west; overlapped the carbonate (eastern), transitional, and siliceous-volcanic (western) assemblage rocks on the flanks of the belt; and locally accumulated within the belt. Roberts and Lehner (1955) proposed that these rocks be called the overlap assemblage. The overlap assemblage in the Betty O'Neal area is represented by the Antler sequence. (Pennsylvanian and Permian Systems - Antler Sequence): The Antler sequence in the project area includes two units, the Battle Formation and the Antler Peak Limestone. The Battle Formation of Middle Pennsylvanian age crops out on the southwest flank of a ridge located just west of Lower Whisky Canyon in section 22 (Plates IV & V). Most of the Battle Formation consists of coarse conglomerate, which is clast supported. The clasts, up to two inches across, consist of chert, quartzite, and quartz grains set in a very fine-grained siliceous matrix. The colors of the clasts and the matrix are very similar, with varying shades of blue, purple, red, and maroon being the most common. All the clasts are well rounded and show only a moderate degree of sorting. Fragments of the underlying beds are noted in the lower part of the Battle, so there is no question of its depositional contact on the Valmy Formation. Interbedded with the conglomerate is pure limestone (similar to Antler Peak Limestone except it lacks fossils), fine-grained limey sandstone, and coarse-grained, poorly sorted sandstone. Both a decrease in the total amount of conglomerate relative to total amount of pure limestone, marks the gradual change from Battle to the overlying Antler Formation. The Battle Formation is approximately 120 feet thick. The Antler Peak Limestone of Late Pennsylvanian and early Permian age crops out in the same area as the Battle Formation (Plates IV & V). Beds strike N20-300 W and dip steeply to the northeast (75-85°). The limestone lies conformably above the Battle Formation. The total thickness is approximately 250 feet. The dominant lithology is a medium to dark gray crystalline limestone, locally fossiliferous, with a few irregular nodules of black chert which are elongate parallel to bedding. The nodules vary from one to ten em. in width and up to four inches to five feet thick, with an average thickness of four feet. The limestone is highly organic. Havallah Sequence: Rocks of the siliceous-volcanic province (Fig. 8) exposed in the area include an assemblage of rocks assigned to the Havallah Formation. The unit probably consists of an inter-leaving of thrust slices, some of Pennsylvanian and some of Permian age. The formation is considered to be dominantly a deep water oceanic or marginal sea deposit. The assemblage was tectonically thrust eastward (and piled up on the west margin of the Antler orogenic belt) over shallow water, in part coeval, rocks (conglomerate-carbonate province). The emplacement occurred along the Golconda thrust during the Sonoma orogeny in Late Permian and Early Triassic. (Silberling and Roberts, 1962, p.l6). 15 ( (Pennsylvanian and Permian Systems - Havallah Formation): Madrid (1987, p.181) notes that the principal exposures of Havallah in the mapped area are located on the ridge and southwest wall of Lower Whisky Canyon (Plate V). He states that the Havallah was found to be somewhat lithologically diverse and occurred always in thrust fault contact (the Golconda thrust) with the underlying Antler Peak Limestone. In the Lower Whisky Canyon area, the Havallah Formation consists of tan, olive-green, maroon, light-grayish-green siliceous and calcareous siltstone, dark brown to black argillite, minor chert, and fine to medium-grained calcareous sandstone. Some thin-bedded limestone occurs within the section. The upper contact is an angular unconformity with the overlying Triassic-Panther Canyon Member of the Augusta Mountains Formation. MESOZOIC STRATA: Mesozoic rocks consist primarily of shallow water carbonate and detrital units. Triassic System - Panther Canyon Member of the Augusta Mountains Formation: Rocks assigned to the Panther Canyon Member crop out on the ridge located near the mouth of Lower Whisky Canyon (Plate V). The sequence includes interbedded sandy limestone and dolomite, clast-supported conglomerate, and matrix supported conglomerate. According to Madrid ( 1987, p.185), the clast supported conglomerates contain large subangular to angular clasts of gray fossiliferous limestone, cream-colored dolomitic sandstone, scarlet red spiculitic chert, and in the lowest exposures of these conglomerates, angular quartz vein material and siltstone derived from the Havallah sequence. Well-rounded clasts are predominantly gray chert and quartzite. Matrix sup~rted, maroon colored conglomerates contain angular clasts of quartzite; greenstone; reddish, micaceous, and feldspathic sandstone; quartzitic sandstone; friable, calcareous quartz sandstone; maroon, micaceous, well-bedded quartz sandstone and siltstone; and minor limestone in a fine to medium-grained matrix made up of fine chips of maroon, micaceous platy siltstone and shale (Madrid, 1987, p.185). Madrid (1987, p.184) found that the conglomeratic beds above the Havallah were deposited on an angular unconformity. The minimum angle between beds of the Havallah and the overlying Panther Canyon conglomerate is between 25 to 40 degrees. IGNEOUS ROCKS Igneous rocks in the area of this study consist mostly of Oligocene intrusive and extrusive units. The intrusive rocks are distributed over much of the area while outcrops of the extrusive rocks are limited to the range front. 16 ( INTRUSIVE ROCKS: Olander (1982, p.22) notes that the majority of the intrusive rocks in the project area are porphyritic dikes, with a composition of quartz monzonite or granodiorite. Phenocrysts are usually quartz and plagioclase, with lesser amounts of biotite and hornblende. EXTRUSIVE UNITS: Two types of volcanic rocks are found within the Betty O'Neal/Lower Whisky Canyon area. An older, cream colored rhyodacitic crystal vitric (lithic) tuff containing sanidine, plagioclase, and quartz phencrysts, and a younger, gray colored, dacitic lithic tuff composed of plagioclase phenocrysts both set in a fine-grained matrix of similar composition. Mafic minerals include biotite and hornblende. STRUCTURAL SUMMARY REGIONAL STRUCTURE The regional structure of the project area is dominated by (1) the Late Devonian and Early Mississippian Antler orogenic event; (2) the late Paleozoic and early Mesozoic Sonoma Orogeny in which the Golconda allochthon (Havallah sequence) was emplaced along the Golconda thrust; (3) folded and tilted rocks of the Havallah sequence are overlain along an angular unconformity by Middle Triassic rocks deposited on the Golconda allochthon; and (4) older, normal faults present in the ranges are cut by Tertiary normal faulting associated with the development of modern basins and ranges. PALEOZOIC DEFORMATION Antler Orogeny- Roberts Mountain Thrust: The late Devonian and early ssissippian Antler orogeny resulted in the emplacement of the Roberts Mountain allochthon iddle and lower Paleozoic siliciclastic units) over rocks of the continental shelf (carbonate units) of approximately the same age (Figs.8 & 9). The Antler orogeny was defined by Roberts (1951) for exposures near Antler Peak in Battle Mountain. There, folded and thrust faulted Late Cambrian and Ordovician strata of the RMA are unconformably overlain by a succession of Middle Pennsylvanian to Permian rocks including the Battle Formation at the base, Antler Peak Limestone, and the Edna Mountain Formation at the top of the succession. The Antler orogeny created a highland from which coarse-detritus was shed to the west and east, the latter, into the Antler foreland basin (Roberts and others, 1958, and Roberts and others, 1967); the former into a basin to the west in which strata of the Havallah sequence accumulated (eg. Miller and others, 1984). 17 ~ -:--, . I v"""~; r-~·· . ' . ' ( ~~~ ~ .,..r:::~ . . )., ·-< :_)f) ·-· 7. ' ;, ·;:-_ ... . ·.!i ~t l : Sc , . ., : I 000 COl Sl"toal"tone Range ar••• ...... _ .. ··-···-··-...... - ··· R~rta Uounudna tl"tn.lat npo••d In tectonic windowa FIGURE 9 Simplified geologic map of nonh-central Nevada · modified from Stewan and Catlson (1978). RobertS Mountains and Golconda thrusts shown by solid and dot-dashed line respectively(-t.... m ~~~ ... Ji-;d, /'f 6 ~~ f· 7) . 18 Madrid (1987, p.17) notes that the basinal strata of the RMA have been complexly deformed and the original stratigraphy has been dismembered at all scales. The RMA consists of a younger over older stack of thrust nappes of regional to local extent. The thickness of this structural stack was a minimum of 4600 meters in the northern Shoshone Range (Madrid, 1987, p. 18). The maximum is unknown because of post-emplacement erosion . Structural studies have addressed the direction of movement of the allochthon which was easterly to southeasterly over the continental margin (Roberts and others, 1958).- Within the project area, all of the Valmy Formation is part of the upper plate. The thrust is not exposed in the immediate area, and is estimated to be at a depth of two miles below the present surface (Payne, 19671 p-.- ~1). The nearest location at which the thrust is exposed is five miles south in the Goat Window: Several exposures of the thrust occur along the east side of the • I Shoshone Range . . · · Sonoma Orogeny - Golconda Thrust: During the Sonoma orogeny, upper Paleozoic basinal rocks of the Havallah sequence were thrust over shelf rocks of the continental margin (Fig.8) . This compressional event affected a large area in Nevada and occurred during Late Permian and Early Triassic (Silberling and Roberts, 1962). The Havallah sequence and correlative rocks comprise the Golconda allochthon which was thrust from west to east across the continental margin (Stewart. 1980). Madrid ( 1987, p. 199) states that the easternmost exposures of the Golconda allochthon in north central Nevada occur in the northern Shoshone Range. Present in the Lower Whisky Canyon area, the Golconda allochthon structurally overlies the overlap assemblage along the Golconda thrust. Post- Upper Paleozoic Tilting: Madrid (1987, p.200) suggests that the angular unconformity between the Upper Paleozoic rocks and Middle Triassic Panther Canyon Member of the Augusta Mountains Formation is significant enough to suggest slight tilting of the entire stack of underlying Paleozoic rocks. Thus, some minor faulting and tilting up to about 20-30 degrees occurred after the emplacement of the Golconda allochthon and before the deposition of Middle Triassic strata. MESOZOIC FOLDING: Madrid (1987, p.200) has established. that the strata of the RMA and depositionally overlying strata as young as Late Triassic have been involved in major, map-scale folding. The folding event is Late Triassic to Late Jurassic in age. The folds on average trend N35W and form fold culminations plunging gently northwest and southeast. 19 ( TERTIARY FAULTING: Tertiary faults are present throughout the area studied and are primarily responsible for disrupting the continuity of older structures. These include faults and fractures that presently dip at high-angles with movement along them spanning a period of time from Oligocene to post-Miocene. The Tertiary structures fall into two basic categories: (1) those that strike northwest and dip southwest, and (2) those that strike east-northeast and dip northerly. Robinson (1989, p.20) notes that th~e two structural orientations are the northwest striking, southwest-dipping, high-angle fault and fracture zones that apparently were responsible for guiding mineralizing solutions into the area. A less prominent conjugate set of north-northeast trending and northwest dipping fractures appears to be the same age as the northwest fractures. The youngest of the two structural episodes includes faulting and fracturing, northeast and some northerly trends, related to the development of post-Middle Miocene Basin and Range faulting. These faults are mostly parallel to sub-parallel to the flanks of the Shoshone Range. PREVIOUS EXPLORATION RESULTS Exploration by Noranda and St. George/Reynolds Metals, including geologic mapping, interpretation of drill data, road cut sampling, and soil geochemistry, strongly suggest that within the range gold and silver mineralization is hosted by veins and shear zones within the Ordovician age Valmy Formation. · NO RANDA Cascade Resources and Noranda Exploration, Inc. entered into an exploration venture in 1980 [ :t ,. 0 in which N oranda ran the program and Cascade provided the funding. As part of their ,1 J 1 I-• • exploration program, Noranda drilled~n-r~ holes for a total of 3,315 feet on the west / ~ .j , side of Rocky Canyon. Olander (1980, f.3rystkle$ that mineralization within their project area ~y,_r u ' could be divided into two types: (1) silver associated with lead and zinc and (2) gold associated with minor amounts of silver. The first type is restricted to quartz-calcite-barite veins occurring in and around the Betty O'Neal, Eagle, Star Grove, and Highland Chief Mines. Nearly all of the production from the Lewis Mining District came from these veins. The second type of mineralization occurs in both veins and shear zones in Upper Whisky Canyon and in Rocky-- -_~~yon .. 20 ( SILVER- LEAD - ZINC VEINS: Silver mineralization occurs in quartz-calcite-barite veins in the form of feibergite (10.1% Ag), galena (.19%), sphalerite (.12%), and pyrite (.09%). Mineralization is restricted to quartz veins and probably related to the occurrence of sphalerite and tetrahedrite. The width of the veins varies from less than one inch up to_lj..fty:-f!Y.e feet. Within the veins, Olander (1980, p.32) notes that the mineralized zones rarely exceed three feet in width and more commonly are only a few inches across. The strike length of the veins is difficult to determine as they often change into stringer zones and slowly die out. The Yankee vein was worked along 600 feet of strike length and down dip for over 300 feet. GOLD: Noranda geologists found gold mineralization associated with both shear zones and veins near the head of Whisky Canyon and on the east side of Rocky Canyon, near its mouth. The Valmy Formation is the host for the mineralized structures. The vein material consists of a variable amount of quartz and calcite. mixed with sulfides. The overall width of individual veins is less than ten feet. Olander (r98o, p.36) states that the gold bearing veins contain more sulfides by volum~, than quartz and calcite, as opposed to the Ag-Pb Zn veins which contain less sulfides than either quartz or calcite. The gold probably occurs in arsenopyrite and pyrite. ( Olander (1980, p.37) suggests that the origin of the gold mineralization was similar to that of the Ag-Pb-Zn mineralization. Late stage hydrothermal solutions, associated with Tertiary igneous activity, circulated through permeable channel ways developed by shearing. As the temperatures and pressure of these fluids decreased, depo~ition of sulfides and gold took place. Noranda developed and tested two exploration models. The first model was for low-grade silver mineralization in the wall rocks adjacent to high-grade silver veins. Their surface samples and drilling indicated that the silver is restricted to the veins, with very little disseminated into the wall rocks. The second model was for low-grade gold mineralization disseminated in a shear zone within the Valmy Formation below a postulated Whisky Canyon thrust fault. Noranda's drilling did indicate an area of discontinuous gold and silver mineral-ization within the Valmy but unrelated to any thrust. / I I)(_ • Vv~ Noranda's drill results are included in Appendix A. J J,..,._, . : o I 21 ( ST. GEORGE/REYNOLDS METALS Based on a continuum of exploration activities (ie. -soil sampling, trenching, geologic mapping, and drilling) concentrated within the range (Red Cap- Lucky Rock - Whisky Canyon claims) from 1987 through 1989, it was conCluded that gold and silver mineralization is generally restricted to narrow, usually less than one inch thick, veins that strike north-northwest and dip moderately to steeply to the southwest (Plate IV). Robinson (1989, p.1) states that the gold and silver veins are found within quartz' veins which tend to occur along the. south-central portion of the property in discreet, sheeted vein zones that are roughly 50 to 200 feet in thickness (Plate IV). According to Robinson (1989, p. l), the quartz veins contain a variety of sulfides including pyrite, arsenopyrite, galena, sphalerite, chalcopyrite, and tetrahedrite together with bismuth tellurium-lead sulfides and sulfosalts. Gold is closely associated with the latter sequence of minerals. Robinson (1989, p.l) states that it is not uncommon for select samples taken from individual vein ~ it_hin_ tn~ sheeted · nes to assay as high as 50 oz Au/ton. ------~ A total 'OL B - oles (~27 rotary and 6 core-HQ) ha~e bee~ d~lle? in the Lucky ~ock- Red Cap area for-a-comblnea rootage-or_ 49,69~.8 _ ieet" A dnll mdicated "geologic resource" of approximately 1,000,000 tons grading 0.026 oz. Au/ton with a cut-off grade of 0.010 oz. Au/ton has been calculated. Mineralized drill intercepts for the Lucky Rock- Red Cap area are given in Appendix B. In the upper Whisky Canyon area, gold and silver values are again associated wit~ thin quartz veins that strike north-northwest and dip steeply to the southwest. St. George/Reynolds' drilling along these mineralized structures has outlined a "geologic resource" of approximate! y 445,000 tons grading 0.036 oz. Au/ton at a cut-off grade of 0.010 oz. Au/ton. . . CYPRUS ACTIVITIES Cyprus geologists and contract personnel have spent approximately 3+ months in assembling, examining, and interpreting St. George Metals' and in-house generated data. GEOLOGY As stated previously, geologic mapping was initiated at scales of 1"= 1000 ft. and 1" =200 ft.. ARL mapped the area around Lower Whisky Canyon (Plate V) and David Blake aided in the regional interpretation (Plate IV). Rock types are discussed in a previous section under general geology. 22 ------ ( It is important to note that the recognition by Madrid (1987) of the Havallah sequence in the Betty O'Neal/Lower Whisky Canyon area enhances the exploration for gold mineralization below the Golconda thrust within the more receptive Antler sequence. LOCAL STRUCTURE Three major high-angle fracture sets are present in the Betty O'Neal/Lower Whisky Canyon region. The two most significant trends are N40 to 50" Wand N50 to 70" E (Plates IV and V). The third set trends north-south and is best expressed in the southern and eastern part of the study area (Plate IV). The northeast and north-trending faults represent basin and range tectonic activity and are considered to be some of the youngest faults in the area. Blake (1992, p.12) notes that most of the mapped dikes occupy structures of the three fracture systems. He notes further, that since some of these dikes are associated with mineralization along these trends, it is apparent that the structural pattern observed was well established prior to mineralization and igneous activity. Thrust faults or low-angle structures are less evident. Theodore ( 1991) and others have recognized numerous thrust slices in other regions within both the Pennsylvanian-Permian age ( Havallah sequence and the Ordovician age Valmy Formation. Thus it is reasonable to assume the same in the project area. Within Lower Whisky Canyon, a N30 to 40" W high angle fault has down-dropped rocks on the north side of Whisky Canyon relative to the south (Plate V). The significance of the movement is that a favorable gold host; Antler sequence, should' be preserved beneath the HavaVah sequence. In addition, in the same area, a northeast-southwest striking, high-angle fault cuts outcropping Antler sequence and down-drops the· unit under Havallah and alluvial gravels (Plate V). As noted by Robinson (1989, p.20) the northwest striking, high-angle fault and fracture zones apparently were responsible for guiding mineralized solutions into the region. The N50 to 70" E, northwest- dipping structural fabric is considered the youngest observed and generally crosses the property parallel to the topographic slope. The type and amount of displacement along these faults is very difficult to determine. 23 ( MINERALIZATION A detailed study of the mineralization in the Betty O'Neal Mine and adjacent mines and prospects was not undertaken. Drill information on the Whisky Canyon and Lucky Rock-Red Cap claims is given in the section on Previous Exploration Results. During the field examination, some of the prospect pits and mine dumps were briefly examined to gather information pertaining to sulfide mineralogy, structural control, and the relationship of mineralization and intrusive activity. Blake (1992, p.l4) mentions that at several localities within the range, sulfide introduction is closely associated with altered and mineralized dikes. In the SE 1/4 of section 28, quartz monzonite porphyry and rhyolite porphyry dikes exhibit sulfide mineralization. Blake (1992, p.14) notes that several joint sets in both quartz monzonite porphyry and rhyolite porphyry dikes are coated with iron-oxide minerals, and disseminated pyrite occurs in the groundmass of the dikes. At Lower Whisky Canyon, evidence of sulfide introduction is restricted to iron-oxide material found along fractures and shear zones. ( In the Betty O'Neal Mine area, dump material from the lower workings contain silver-rich galena, pyrite, tetrahedrite, sphalerite, and abundant white, coarse crystalline calcite. Much of the area, where adits have been driven to intersect mineralization associated with the Betty O'Neal Mine, is covered by thick soils and slope wash. However, mineralization apparently occurs in a northwest-trending structure (Tingley, 1969). ALTERATION Hydrothermal alteration effects within the Lower Whisky Canyon area are confined to Havallah and Panther Canyon rocks cropping out near the mouth of Whisky Canyon (Plate V). Alteration products consist of silicification (silica flooding within carbonate units and quartz veining); decalcification; minor development of calc-silicate veining (wollastonite, epidote, and calcite); and clay minerals. These hydrothermal alteration features occur in or adjacent to mineralized structures, usually sulfide-bearing. The carbonate rocks of the overlap assemblage forming the ridge south of Lower Whisky Canyon are unaltered. 24 ( At the Betty O'Neal Mine, hydrothermal alteration is chiefly represented by clay minerals, silicification (quartz veining and/or silica flooding), and sericitization. These alteration products do not "appear" to be extensively developed (much of the area is covered by soil and talus). Apparently only where major structures have allowed fluids to circulate can these alteration effects be observed. GEOCHEMISTRY Rock-chip: Over one hundred (100+) bags of rock-chips were collected from the Lower Whisky Canyon region. Sample locations are shown on Plate VI and Figure 10. The geochemical results are given in Appendix C. 0 / v ~ > ' '5 2 t?f.b ~y .--./ (/'--' _.,- -'l (J.-JQ Rock-chip samples were specifically collectedrfrbm mineralized (altered) rock and mineralized structures/shears. The highest gold value is_l. 195 ru>-M- obtained from a N 20° E striking structure cutting Havallah sequence rocks (Plate VI). Numerous other anomalous gold and associated silver, arsenic, antimony, and zinc values are reported from the same area (Plate VI). It is the author's opinion that the metals represent lateral leakage from a covered, structural, Antler sequence hosted gold deposit. Soil: One hundred and ninety-two (192) soil samples were collected on a 50' X 200' grid. Plates VII, VIII, IX, X, and XI show values obtained for gold, silver, arsenic, antimony, and zinc respectively. It is important to note that high concentrations of each element are associated with the N 45° W trending Lower Whisky Canyon fault. In addition all elements continue in excess to the northwest, under cover. · GEOPHYSICS Plate XII shows Frank Fritz's (geophysical consultant) interpretation of aeromagnetic, ground magnetic, and IF/Resistivity data furnished by St. George Metals and Cyprus files (Gulf Minerals Resources). · Magnetics: Fritz (1992, p.9) states that there are generally three types of magnetic sources in the region: the large remnant low north of the Betty O'Neal Mine; small magnitude magnetic highs scattered throughout the area; and very small extent and small magnitude highs also scattered throughout. The large magnetic low is probably a flow of a remnantly induced volcanic unit with a possible small dike along a NNW structure. The profile data suggests that there are more of these flows, but they are thin in most other areas. 25 ~ ·. . "• . ( The small magnetic highs correlate with a variety of igneous dikes and small intrusives on the geologic map and with Tertiary volcanic units. Almost all mapped outcrops of these volcanics show a small, 1 to 5 nT high associated with them. The small magnitude suggests that they have a low magnetic susceptibility and are relatively thin. The smallest magnetic responses appear to relate to thin dikes of several rock types. Typical magnitudes are less than 5 nT. None of these appear to correlate between lines. Gradient breaks are interpreted to be structures defining edges of low susceptibility bodies. The most prominent of these is a NNW structure that cuts the remnant low (Plate XII-A). This is on strike of the Betty O'Neal structure but cannot be extended that far southeast by the magnetic data. The other major structures appear to be a set of northeast basin faults with offsets on northwest structures. These sets may form a series of ramps downdropped to the northwest and ramping to the southwest into the valley. None of the magnetic responses can be associated with any possible mineralization. IP/Resistivity: Fritz (1992, p. 7) notes that the four lines of Time Domain IP/Resistivity data collected for Gulf by Scintrex did not cover a significant area and are not very detailed (Plate XII). Through most of the western part of the lines, the resistivities reflect the same features as the TDEM data: a moderate resistivity layer on a lower resistivity layer. Again this is probably the water table. The south-eastern end of line "C" extends onto outcrop into mapped Valmy Formation (Plate XII). The resistivities and IP effects both increase, probably indicating the background values associated with the unit itself. There is a suggestion of a westerly dip but there is insufficient data to be conclusive. On line "B" the south-eastern end does not quite reach outcrop but the resistivities start up at the end, as on line "C" (Plate XII). The IP effects are quite erratic to the west of the resistivity increase in possible lower resistivity volcanic rocks. The source is unclear. 27 l Line "A" shows higher resistivities at larger 'n' spacings towards the southeast, possibly indicating a thin cover over Valmy (Plate XII). The IP effects increase slowly, however, suggesting a different rock type. Line "A-0" is short and on outcrop (Plate XII). There are significant structures mapped in the area. Resistivities are low compared to other lines .on outcrop, but the IP effects are typical for Valmy. The structures may be lowering the resistivity. Only the higher but erratic IP effects on line "B" appear to be reflecting sources other than bedrock units and may be of economic interest. Fritz (1992, p.2) concludes that the collection of geophysical data in the Betty O'Neal area has defined several magnetic sources and resistivity contrasts. The majority of the magnetic sources appear to be from volcanics and small intrusives. Most of the electrical responses appear to be from background values in bedrock units and contrasts due to the water table. Based on the geophysical data, Fritz (1992, p.2) concludes that two exploration opportunities appear to exist: (1) The magnetically defined structure (A) striking into the Betty O'Neal Mine area is ( considered to be the most promising exploration target (Plates XII & XIII). The complex area on IP/Resistivity line "B" is also on strike of this structure. Drill holes P-4, 5, and 6 should have been close to this structure but may have still been too far north to test the IP source. Again only one line of IP data does not allow definition of the source. The exact location of the NNW structure is only defined by 200' station spacing r11agnetic data. This wide spacing will not allow locations bett~r than about 200 to 400' . (2) The IP/Resistivity data on line "B" suggests a complex response just to the northwest of the Betty O'Neal Mine (Plates XII & XIII). Fritz (1992, p.3) recommends additional IP/Resistivity lines in the area of the complex IP high on Line "B". A minimum of three lines are needed to define the three dimensional location of . a possible source. An estimated cost of $6,000 to $10,000 would be sufficient to determine / 1 possible exploration targets. The line orientation probably should be easterly to cross the \ interpreted Betty O'Neal structure. \ . \ r I ~- \. J I \ ' r \ . \ 28 . .\ ' LINEAMENTS Plates IV and XIII show major and minor linear trends interpreted by IntraSearch, Inc. from Landsat color composite Thematic Mapper (TM) imagery; IntraSearch 1:24,000 color aerial photographs; and available published lineament, fracture, and fault data. Plate IV illustrates the features for the entire St. George land block, and. Plate XIII details the Betty O'Neal/Lower Whisky Canyon region. The soil geochemical information appears to verify the existence of the N 30" E lineament located in Lower Whisky Canyon and its control on recorded mineralization. Thus it is suggested that a "major" gold deposit could be hosted by Havallah and Antler rocks near the intersection of the Lower Whisky Canyon fault and the range bounding northeast-southwest trending structure (Plates V, XIII, and Figure 11). These structures represent a conjugate fracture set that may have been open at the time of gold introduction; occurring at the inception of Basin and Range extension. The fracture intersections being more permeable would have been favorable sites for solution channeling and gold deposition. If the above scenario is correct, then other exploration targets exist in the area. ( RECOMMENDATIONS Recommendations are given for both the Betty O'Neal Mil)e and Lower Whisky Canyon trends. Most of the work should be concentrated in the pediment area along both the Betty O'Neal and Lower Whisky Canyon structures. Exploration activities should consist of: · (1) Land acquisition of the Betty O'Neal claim block in section 22. (2) Lease Red Cap claims from St. George. (3) Geophysical survey to accurately define the locations of major fracture intersections ~-) (solution channeling and gold deposition). (4) Drill by rotary reverse circulation methods a number of holes to test for gold mineralization along structures/structural intersections and in the buried Havallah and Antler sequence. t' ,' r ( l\ ,' .!P A.R. Leger r ' ' l ~1 , , I 4 ·, • f ./.. r. . /1 , , • : f.'·-' \ ·- '"\ I I //~ .-,, ( J. · ·' J I 29 • , •• • ••1 • : 'I . I "') ', "' .~ ' ~ I) • ,Ad ; -1 ,.., l.- ' .' " r ) / ! ' BETTY O'NEAL - Propose Lo A ELEVATION (feet) 5600 Oaf Qat -- Trd-- __ Trd 5400 -- -_j- - Trpc - - Trd --- Pchs --- Trpc -- Pchs ~~Y~..,. _. '!r > Trpc ~ _ ~Pchs 5200 x 'x:'X 5&-- Ov )( ~v PPab "><>< ~~ 5000 > 4800 Ov Ov 4600 4400 2·00 12· 00 14.00 [ ~ WHISKY CANYON c Section 5W A' ELEVATION (feet) / . / 1 Ool . ------; I -- -Tr~ 1I ------I Trpc j ~lcofldo Pchs -· 4 / PP@ 5000 4800 Uncon forrnity ~~ ~ 4600 Ov ~~ ~ ~~ ~ 4400 18·00 20·00 22·00 26. 00 28·00 30·00 32·00 Proposed Gold Target ~' ------~~~:_· ~:------~------F-Igu_r_e __ll , - 30 Figure II BETTY O'NEAL - LOWER WHISKY CANYO Proposed Geologic Section Looking N45W IP HIGH tJ#IIIIJJIJIIIII(I}.I)fl,i.J ·rpc Trd --~------/ / Qol 'chs _- r----Trd I -...... --- ; ; ---- ;:h~ ~ Trpc- --. '-..! ..._ -- -._ / Trd -4_Pch• / r ---- ~ "'---4_ - A I ~ I ~lco"!0 A : PPab / / PPab / 1 1~f -r l':!::. ? Unconformity c?~ Ov ~ Ov ~l f l~ ~ / i -'!! Ov ~ ~~ ~ / ~ / ~~ l 6·00 10·00 12·00 14+00 16·00 16 · 00 20•00 22·00 DISTANCE (feet) • REFERENCES CITED ( Blake, D.W., 1992, Report on the Betty O'Neal Mine Area - Lander County, Nevada: Unpublished Report for Cyprus Metals Company, 20pp. Broderick, J.P., 1988, Geological report on the Fisher Gold Project: Unpublished Report for St. George Minerals, Inc., 54pp. Fritz, F.P., 1992, A review of a collection of geophysical data over the Lewis Area- Lander County, Nevada: Unpublished Report for Cyprus Metals Company, 10pp. Gulf Mineral Resources Company, 1975, Interpretation of gravity, magnetic, and induced polarization data in the Battle Mountain and adjacent areas, Nevada: unpublished report, 21pp. ~wrence, E.F., 1965, Betty O'Neal Mine, Lander County, Nevada: unpublished report, 18pp. Madrid, R.J., 1987, Stratigraphy of the Roberts Mountains Allochthon in North-Central Nevada: Unpublished Ph.D. thesis, Stanford University, 340pp. Miller, E.L., Holdsworth, B.K., Whiteford, W.B., and Rodgers, D., 1984, Stratigraphy and structure of the Schoonover sequence, northeastern Nevada: Implications for Paleozoic plate margins tectonics: Geol. Soc. America Bull., V.95, no.9, p.1063-1076. Mineral Industries Engineers, Inc., 1975, Report of impressions on the Betty O'Neal mineral lands, Lewis Mining District, Lander County, Nevada: unpublished report, 24pp. . / VOlander, Peter R., 1981, Betty O'Neal Project (0552)- summary report- 1980: Unpublished Report for Noranda Exploration, Inc., 52pp. / v Payne, A.L., 1967, Geological report on the Betty O'Neal Silver Mine, Lewis Mining District, 7 Lander County, Nevada: unpublished report, 68pp. / Pierce, J.C., 1976, Report on the Betty O'Neal silver prospect, Lewis Mining District, Lander County, Nevada: unpublished report, 16pp. Roberts, R.J., 1949, Geology of the Antler Peak quadrangle, Nevada: U.S. Geological Survey Open File Report. Roberts, R.J., 1951, Geology of the Antler Peak quadrangle, Nevada: U.S. Geological Survey Geological Quadrangle Map GQ-10, scale 1:62,500. Roberts, R.J., and Lehner, R.E., 1955, Additional data on the age and extent of the Roberts Mountain thrust fault, north-central Nevada (abs): Geol. Soc. America Bull., V.66, p. 1661. 31 • ( Roberts, R.J., Holts,P.E., Gilluly, J., and Ferguson, H.G., 1958, Paleozoic rocks of north central Nevada: American Association Petroleum Geologist Bulletin, V. 42, p.2813-2857. Roberts, R.J., Montgomery, K . M., and Lehner, R. E., 1967, Geology and mineral resources of Eureka County, Nevada: Nevada Bureau of Mines and Geology Bull. 64, 152pp. Robinson, Michael L. , 1989, Summary report- Fisher Gold Project- Lander County, Nevada: Unpublished Report for St. George Metals,- Inc., 78pp. Silberling, N.J. and Roberts, R.J., 1962, Pre-Tertiary stratigraphy and structure ofnbrthwestem Nevada: Geol. Soc. Special Paper 72, 58pp. St. George Minerals, Inc., 1988, Summary data- Northern Nevada projects, unpublished report, 33pp. Stephenson, E.L., 1956, Report on the exploration at the Betty O'Neal Mine, Lander County, )< Nevada: unpublished report, 12pp. Stewart, J.H., 1980, Geology of Nevada: Nevada Bureau of Mines and Geology Special Publication 4, 136pp. Theodore, T.G., 1991, Preliminary geologic map of the Valmy Quadrangle, Humboldt County, Nevada: U.S. Geol. Survey open-file report 91-430. Tingley, J. V ., 1969, Underground geology and exploration potential of the Betty O'Neal Mine: "\. J unpublished report. )< 32