Locatable Mineral Reports for Colorado, South Dakota, 

and Wyoming provided to the U.S.D.A. Forest Service in 

Fiscal Years 2003-2005 

By Anna B. Wilson 

Open-File Report 2006–1018

U.S. Department of the Interior 

U.S. Geological Survey 
i

CONTENTS

page

INTRODUCTION .................................................... . . 6

COLORADO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Arapaho/Roosevelt National Forests

Golden Conveyance (locmin82) ................................ 9

Routt/Gunnison National Forests

Big Creek Ranch (Needmore Ranch) Exchange (locmin79) ........... 1 7

Pike/San Isabel National Forests

Round Hill (City and County of Denver) Exchange (locmin76) ........ 3 2

San Juan/Pike/San Isabel National Forests

Laughlin Park Exchange (locmin81) ............................. 4 2

San Juan National Forest

Fish Creek Exchange (locmin88) ............................... 5 3

Uncompahgre National Forest

Kent/Lindsay Exchange (locmin86) ............................. 6 4

Telluride Airport Exchange (locmin89) . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3

White River National Forest

South Game Creek (Vail Corporation) Exchange (locmin83) ......... 8 3

SOUTH DAKOTA ..................................................... 9 1

Black Hills National Forest

Cattail Exchange (locmin87) .................................. 9 2

Nebraska National Forest

Buffalo Gap National Grasslands 

Cole Draw (Edoff) Exchange (locmin 75) ....................... 1 0 5

Cortney Creek Ranch (Sides Ranch) Exchange (locmin 80) . . . . . . . . . . 1 1 3

Indian Creek Exchange (locmin84) ............................ 1 2 0

Fort Pierre National Grasslands

Missouri Breaks exchange (locmin78) .......................... 1 2 9

WYOMING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 3 8

Bighorn/Black Hills National Forests

City of Buffalo (Tie Hack Reservoir) Exchange (locmin 77) . . . . . . . . . 1 3 9

Medicine Bow National Forest

Thunder Basin National Grasslands 

Cow Creek (Thomson) Exchange (locmin 85) . . . . . . . . . . . . . . . . . . . . 1 4 9

2
ii

FIGURES

COLORADO

Arapaho/Roosevelt National Forests

Golden Conveyance (locmin82)

Fig. 1. Attachment A (Report Request) . . . . . . . . . . . . . . . . . . . 13

Fig. 2. Attachment B (Location description) . . . . . . . . . . . . . . . . 1 4

Fig. 3. Attachment C (Geologic map, non-Federal) ........... 1 5

Fig. 4. Attachment D (Geologic map, Federal) . . . . . . . . . . . . . . 1 6

Routt/Gunnison National Forests

Big Creek Ranch (Needmore Ranch) (locmin79)

Fig. 5. Attachment A (Report Request) . . . . . . . . . . . . . . . . . . . . 2 4

Fig. 6. Attachment B (Exhibit A) . . . . . . . . . . . . . . . . . . . . . . . . . 2 5

Fig. 7. Attachment C (Exhibit B) . . . . . . . . . . . . . . . . . . . . . . . . . 2 8

Fig. 8. Attachment D (Geologic map, Hahns Peak) . . . . . . . . . . . 2 9

Fig. 9. Attachment E (Geologic map, Kebler Pass) . . . . . . . . . . . 3 0

Fig. 10. Attachment F (Geology, Federal) .................. 3 1

Pike/San Isabel National Forests

Round Hill (City and County of Denver) (locmin76)

Fig. 11. Attachment A (Exhibits A and B) . . . . . . . . . . . . . . . . . . 3 8

Fig. 12. Attachment B (Report Request) . . . . . . . . . . . . . . . . . . . 3 9

Fig. 13. Attachment C (Geologic map, Federal and non-Federal)

Fig. 14. Attachment D (Geologic map, non-Federal) .......... 4 1

San Juan/Pike/San Isabel National Forests

Laughlin Park (locmin81)

Fig. 15. Attachment A (Exhibit A) . . . . . . . . . . . . . . . . . . . . . . . 4 8

Fig. 16. Attachment B (Exhibit B) . . . . . . . . . . . . . . . . . . . . . . . . 4 9

Fig. 17. Attachment C (Report Request) . . . . . . . . . . . . . . . . . . . 5 0

Fig. 18. Attachment D (Geologic map, Federal, non-Federal) . . . 5 1

Fig. 19. Attachment E (Geologic map, non-Federal) .......... 5 2

San Juan National Forest

Fish Creek (locmin88)

Fig. 20. Attachment A (Exhibit A) . . . . . . . . . . . . . . . . . . . . . . . 5 9

Fig. 21. Attachment B (Exhibit B) . . . . . . . . . . . . . . . . . . . . . . . . 6 0

Fig. 22. Attachment C (Report Request) . . . . . . . . . . . . . . . . . . . 6 1

Fig. 23. Attachment D (Geologic map) . . . . . . . . . . . . . . . . . . . . 6 2

Fig. 24. Attachment E (Geologic map) . . . . . . . . . . . . . . . . . . . . 6 3

3
iii

Uncompahgre National Forest

Kent/Lindsay Exchange (locmin86)

Fig. 25. Attachment A (Report Request) . . . . . . . . . . . . . . . . . . . 6 9

Fig. 26. Attachment B (Exhibits A a

Fig. 27. Attachment C (Geologic map, Non-Federal) .......... 7 1

nd B) .................. 7 0

Fig. 28. Attachment D (Geologic map, Federal) . . . . . . . . . . . . . 7 2

Telluride Airport (locmin89) 

Fig. 29. Attachment A (Exhibits A and B) . . . . . . . . . . . . . . . . . . 7 8

Fig. 30. Attachment B (Report Request) . . . . . . . . . . . . . . . . . . . 7 9

Fig. 31. Attachment C (Geologic map) . . . . . . . . . . . . . . . . . . . . 8 0

Fig. 32. Attachment D (Geologic map) . . . . . . . . . . . . . . . . . . . . 8 1

Fig. 33. Attachment E (Geologic map) . . . . . . . . . . . . . . . . . . . . 8 2

White River National Forest

South Game Creek (Vail Corporation) (locmin83)

Fig. 34. Attachment A (Report Request) ................... 8 8

Fig. 35. Attachment B (Location description, Exhibits A and B). . 8 9 

Fig. 36. Attachment C (Geologic map) . . . . . . . . . . . . . . . . . . . . 9 0

SOUTH DAKOTA

Black Hills National Forest

Cattail Exchange (locmin87)

Fig. 37. Attachment A (Exhibit A) . . . . . . . . . . . . . . . . . . . . . . . . 99

Fig. 38. Attachment B (Exhibit B) . . . . . . . . . . . . . . . . . . . . . . . . 1 0 0

Fig. 39. Attachment C (Report Request) . . . . . . . . . . . . . . . . . . . 1 0 1

Fig. 40. Attachment D (Geologic map) . . . . . . . . . . . . . . . . . . . . 1 0 2

Fig. 41. Attachment E (Geologic map) . . . . . . . . . . . . . . . . . . . . 1 0 3

Fig. 42. Attachment F (Geologic map) . . . . . . . . . . . . . . . . . . . . . 1 0 4

Nebraska National Forest

Buffalo Gap National Grasslands

Cole Draw (Edoff) Exchange (locmin75)

Fig. 43. Attachment A (Exhibit A) . . . . . . . . . . . . . . . . . . . . . . . 1 0 9

Fig. 44. Attachment B (Exhibit B) . . . . . . . . . . . . . . . . . . . . . . . . 1 1 0

Fig. 45. Attachment C (Report Request) . . . . . . . . . . . . . . . . . . . 1 1 1

Fig. 46. Attachment D (Geologic map) . . . . . . . . . . . . . . . . . . . . 1 1 2

Cortney Creek (Sides Ranch) Exchange (locmin80)

Fig. 47. Attachment A (Location map) . . . . . . . . . . . . . . . . . . . . 1 1 6

Fig. 48. Attachment B (Exhibit B) . . . . . . . . . . . . . . . . . . . . . . . . 1 1 7

Fig. 49. Attachment C (Report Request) . . . . . . . . . . . . . . . . . . . 1 1 9

Indian Creek (Sides Ranch) Exchange (locmin84)

Fig. 50. Attachment A (Report Request) . . . . . . . . . . . . . . . . . . . 1 2 5

Fig. 51. Attachment B (Exhibit A) . . . . . . . . . . . . . . . . . . . . . . . . 1 2 6

Fig. 52. Attachment C (Exhibit B) . . . . . . . . . . . . . . . . . . . . . . . . 1 2 7

4
iv

Fig. 53. Attachment D (Geologic map) . . . . . . . . . . . . . . . . . . . . 1 2 8

Fort Pierre National Grasslands

Missouri Breaks Exchange (locmin78)

Fig. 54. Attachment A (Report Request) . . . . . . . . . . . . . . . . . . . 1 3 3

Fig. 55. Attachment B (Exhibit A) . . . . . . . . . . . . . . . . . . . . . . . . 1 3 4

Fig. 56. Attachment C (Exhibit B) . . . . . . . . . . . . . . . . . . . . . . . . 1 3 5

Fig. 57. Attachment D (Index map) . . . . . . . . . . . . . . . . . . . . . . . 1 3 6

Fig. 58. Attachment E (Geologic map) . . . . . . . . . . . . . . . . . . . . 1 3 7

WYOMING

Bighorn/Black Hills National Forests

City of Buffalo (Tie Hack Reservoir) (locmin77)

Fig. 59. Attachment A (Exhibit A) . . . . . . . . . . . . . . . . . . . . . . . 1 4 3

Fig. 60. Attachment B (Exhibit B) . . . . . . . . . . . . . . . . . . . . . . . . 1 4 4

Fig. 61. Attachment C (Report Request) . . . . . . . . . . . . . . . . . . . 1 4 5

Fig. 62. Attachment D (Geologic map, non-Federal) .......... 1 4 6

Fig. 63. Attachment E (Geologic map, Federal) . . . . . . . . . . . . . . 1 4 7

Fig. 64. Attachment F (Index map) . . . . . . . . . . . . . . . . . . . . . . . 1 4 8

Medicine Bow National Forest

Cow Creek (Thomson) Exchange (locmin85)

Fig. 65. Attachment A (Report Request) . . . . . . . . . . . . . . . . . . . 1 5 2

Fig. 66. Attachment B (Exhibits A and B) . . . . . . . . . . . . . . . . . . 1 5 3

Fig. 67. Attachment C (Geologic map) . . . . . . . . . . . . . . . . . . . . 1 5 4

5
6

Locatable Mineral Reports for Colorado, 

South Dakota, and Wyoming provided to the 

U.S.D.A. Forest Service in Fiscal Years 2003-2005 

By Anna B. Wilson

Introduction 

The U.S. Geological Survey is required by Congress (under Public Law 86-509) to provide 

Locatable Mineral Reports to the U.S.D.A. Forest Service whenever National Forest System lands

are sold or exchanged. This volume is a compilation of the reports already provided to the Forest 

Service by the author in fiscal years 2003-2005 (October 2002 - September 2005). Altogether, the 

reports describe the geology and locatable mineral resource potential of 74 properties offered in 15 

land exchange proposals. Approximately 16,207 acres were evaluated: 9,176 acres in 31 Federal 

parcels and 7,031 acres in 43 non-Federal parcels. The parcels are located in 13 National Forests 

and three National Grasslands in three States. 

 Locatable Mineral Reports provide a summary of the geology and a subjective appraisal of 

the mineral resource potential of land parcels considered for exchange. Information in each report 

is based on a review of published maps and reports, unpublished data in U.S. Geological Survey 

files, the professional expertise of the writer, and interviews with other knowledgeable 

geoscientists. Site visits are conducted only where it is deemed necessary (due to lack of available 

supporting or conflicting information), expedient, or cost-effective--only two days of field 

investigations support the reports included in this volume. The mineral resource information 

provided is used in making relative comparisons of the potential future mineral value of lands being 

offered in an exchange and in appraising the value of the land. Future mineral potential value is 

subjectively expressed in qualitative terms using a three-tier nomenclature of "high", "moderate", 

and "low". In general, "high" is applied where mineral deposits are present on the property or 

adjacent to it, or there are other indications that the area has been mineralized. "Moderate" is 

applied where mineralization is only suspected or where an area possesses some of the same 

geologic characteristics that are common to areas around known mineral deposits. A "low" value is 

routinely applied to all remaining areas, with the understanding that the information required to 

prove the absence of any mineral resource potential will never be available. Copies of the reports 

reside in U.S. Geological Survey Mineral Resource Program and U.S.D.A. Forest Service files. 

 Most recent land exchanges are proposed for mutual convenience to gather both Federal and 

private lands into manageable blocks. Land exchanges are being used to mitigate management and 

utilization problems associated with commingled Federal and private property ownership. 

Promotion of greater continuity of ownership and creation of more manageable and useable 

property units play an influential role in the property selection and consolidation process. Some 

proposals are by Towns, Counties, and States wishing to acquire lands to serve the common good 
7

of their constituencies. Others are motivated by ranchers wishing to consolidate or expand their 

grazing lands and increase the efficiency of their operations. Still others are proposed by owners of 

remote patented mining claims wishing to trade their tracts for more accessible parcels or to avoid 

liability for any potential hazards the site may develop as a result of prior mining. Many recent 

land-exchange offers are directed toward acquisition of public lands in high-value recreation areas 

(such as ski areas). Increasingly, there is more potential for litigation and controversy for land 

exchanges involving high-value real estate than for exchanges of lower profile grazing lands. 

Hence, locatable mineral reports must be reliable enough to withstand scrutiny from litigants vying 

for high-stakes real estate. 

 Fifteen reports are included in this volume. They are grouped by State, then alphabetically 

by Forest. Each starts with a cover letter and title page. Geologic descriptions of properties, their 

mineral potential, and references comprise the main body of each report. Legal descriptions (either 

verbatim or paraphrased from descriptions supplied by the Forest Service) of the property locations 

are included as attachments designated Exhibits A and B. Also included as attachments are the 

report request from the U.S.D.A. Forest Service and any index maps, geologic maps, or other 

figures or illustrations that are provided for the convenience of the Forest Service minerals 

examiner. The original page numbers for each individual report are retained, the larger number at 

the bottom of each page is the pagination for this volume. 
COLORADO

8
C:\...\locmin\locmin82.wpd November 17, 2004

LOCATABLE MINERAL REPORT FOR THE

CITY OF GOLDEN CONVEYANCE,

ARAPAHO AND ROOSEVELT NATIONAL FORESTS,

CLEAR CREEK AND PARK COUNTIES, COLORADO

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

November 17, 2004

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author.

9
U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 905

Denver Federal Center

Denver CO, 80225

(303) 236-5593

FAX (303) 236-3200

awilson@usgs.gov

November 17, 2004

Mr. Randall Karstaedt

Director, Physical Resources

U.S. Forest Service

PO Box 25127

Lakewood, CO 80225-0127

Dear Mr. Karstaedt:

This report is in response to your November 4 request for information on locatable mineral

resources in a land exchange proposal in which the Secretary of Agriculture was directed to

convey Federal lands within the Arapaho National Forest to the City of Golden in exchange for

non-Federal lands, also within the Arapaho National Forest. 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in

Attachment B, which was included with your request. These lands comprise approximately 90

acres in Clear Creek and Park Counties, Colorado.

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: C.J. Nutt

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin82.wpd 1 November 17, 2004

The report request is Attachment A. For the legal location description of lands considered for

exchange, refer to Attachment B. Attachments C and D are simplified geologic maps showing

the approximate locations of the Federal and non-Federal parcels.

Non-Federal Lands

Cub Creek

Meridian Hill 1:24,000, Denver West 1:100,000, Denver 1:250,000 quadrangles.

The Cub Creek parcel is located on the northern margin of the Lone Rock Pluton in late Middle

Proterozoic Pikes Peak Granite (approx. 1,039 Ma). At the coarse scale of the available

mapping (1:250,000) and based on Bruce Bryant’s unpublished reconnaissance mapping, the

northernmost part of the parcel may be in the Middle Proterozoic (approx. 1,400 Ma) quartz

monzonite (monzogranite) of the Yankee Creek portion of the Mt. Evans Pluton (Bryant and

Hedge, 1978; Bryant and others, 1981; Bryant, USGS, oral commun., Nov. 21, 2004). 

There are no mines, prospects or mining districts in the vicinity (Wilson, 2003). The nearest

ones are a clay prospect approximately 3.5 mi east, a stone prospect approx. 5 1⁄2 mi. to the south

east, and a beryllium prospect about 5 mi. to the south. Of these, only the last is in the Pikes

Peak Granite host rock. Bruce Bryant (oral commun., Nov. 21, 2004), in his mapping of the

area, had no reason to suspect any mineralization in the vicinity. Mineral resource potential for

locatable minerals is considered to be low.

Federal Lands

Empire

Empire 1:24,000, Denver West 1:100,000, Denver 1:250,000 quadrangles. 

The arrowhead-shaped area included in this exchange is in West Fork of Clear Creek, west of

the town of Empire. It is mapped primarily as undivided Quaternary alluvium, talus, solifluction

debris, and morainal deposits overlying Tertiary monzonitic rocks (Braddock, 1969). 

Mines and prospects in the immediate area include the Hidden Treasure and Allen Lode. 

Descriptions of these mines (Spurr and others, 1908) do not include production figures. The

Hidden Treasure was developed by two tunnels, one of which had “been caved shut for some

years” although it supposedly “produced a considerable ore of exceptionally rich nature” (Spurr

and others, 1908, p. 409). It is said to have “produced the largest and finest specimens of native

gold in the district. This free gold consisted of both leaf gold and of small irregular masses

resembling nuggets.” Cupriferous pyrite, sphalerite and galena were found on the dump (Spurr

and others, 1908, p. 409). When they studied the ore deposits in the Front Range, Lovering and

Goddard (1950, p. 160) briefly summarized Spurr and others’ description of the Hidden

Treasure but did not mention the Allen Lode.

11
C:\...\locmin\locmin82.wpd 2 November 17, 2004

Locatable mineral resource potential of the hillside above the parcel would be high. However,

no mineral resources have been discovered in the valley bottom in spite of relatively intense

operations along the creek. Therefore, mineral resource potential of the parcel is predicted to be

moderate.

REFERENCES:

Braddock, W.A., 1969, Geology of the Empire quadrangle, Grand, Gilpin, and Clear Creek

Counties, Colorado: U.S. Geological Survey Professional Paper 616, 56 p., scale

1:24,000.

Bryant, Bruce, and Hedge, C.E., 1978, Granite of Rosalie Peak, a phase of the 1700-millionyear-old Mount Evans Pluton, Front Range, Colorado: U.S. Geological Survey Journal of

Research, v. 6, no. 4, p. 447-451.

Bryant, Bruce, McGrew, L.W., and Wobus, R.A., 1981, Geologic map of the Denver 1

o

 X 2o

quadrangle, north-central Colorado: U.S. Geological Survey Miscellaneous

Investigations Series Map I-1163, scale 1:250,000.

Lovering, T.S., and Goddard, E.N., 1950, Geology and ore deposits of the Front Range,

Colorado: U.S. Geological Survey Professional Paper 223, 319 p.

Spurr, J.E., Garrey, G.H., and Ball, S.H., 1908, Economic geology of the Georgetown

quadrangle (together with the Empire district), Colorado: U.S. Geological Survey

Professional Paper 63, 422 p.

Wilson, A.B., 2003, Databases and simplified geology for mineralized areas, claims, mines and

prospects in Colorado: U.S. Geological Survey Open-File Report 03-090.

LIST OF ATTACHMENTS:

A. Report Request (provided by U.S. Forest Service).

B. Legal description of Federal land considered in this exchange (provided by U.S. Forest

Service).

C. Simplified geologic map showing location of Cub Creek parcel (modified from Bryant

and others, 1981; Wilson, 2003).

D. Simplified geologic map showing location of the Federal parcel (modified from

Braddock, 1969; Bryant and others, 1981; Wilson, 2003).

12
C:\...\locmin\locmin82.wpd 3 November 17, 2004

Attachment A. Report Request (provided by U.S. Forest Service)

13
C:\...\locmin\locmin82.wpd 4 November 17, 2004

Attachment B. Location description (provided by U.S. Forest Service).

14
C:\...\locmin\locmin82.wpd 5 November 17, 2004

Attachment C. Simplified geologic map showing location of Cub Creek parcel (modified from B

1981; Wilson, 2003). Yp, Middle Proterozoic Pikes Peak Granite (approx. 1,039 Ma) of thPluton, Yg, Middle Proterozoic (approx. 1,400 Ma) quartz monzonite (monzogranite) of thportion of the Mt. Evans Pluton.

15
C:\...\locmin\locmin82.wpd 6 November 17, 2004

Attachment D. Simplified geologic map showing location of the Federal parcel (modified from B

Bryant and others, 1981; and Wilson, 2003). Qa, Quaternary alluvium; Tm, Tertiary monz

Proterozoic gabbro and mafic diorite and monzonite; Xfh, Early Proterozoic felsic and hor

Colored symbols indicate approximate location of mines and prospects, Hidden Treasure amines shown as yellow squares.
C:\...\locmin\locmin79.wpd August 20, 2004

LOCATABLE MINERAL REPORT FOR THE

BIG CREEK RANCH (Needmore Ranch II)

 LAND EXCHANGE OFFER,

ROUTT AND GUNNISON NATIONAL FORESTS,

ROUTT AND GUNNISON COUNTIES, COLORADO

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

Aug 15, 2004

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author.

17
C:\...\locmin\locmin79.wpd August 20, 2004

U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

(303) 236-5593

FAX (303) 236-3200

awilson@usgs.gov

August 20, 2004

Randall Karstaedt

Director, Physical Resources

U.S.D.A. Forest Service

PO Box 25127

Lakewood, CO 80225-0127

Dear Mr. Karstaedt:

This report is in response to your May 25 request for information on locatable mineral resources

in the Big Creek Ranch land exchange proposal in which Needmore Ranch II has offered certain

non-Federal lands within the Routt and Gunnison National Forests in exchange for Federal lands

within Routt National Forest. 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in Exhibits

A and B, which were included with your request. These lands comprise approximately 1597

acres in Routt and Gunnison Counties, Colorado.

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: C.J. Nutt

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin79.wpd 1 August 20, 2004

Original Forest Service Request is in Attachment A. Locations of the lands considered for

exchange are described in Attachments B and C.

Non-Federal Lands

Parcel A. Hahns Peak

Hahns Peak 1:24,000, Walden 1:100,000, Craig 1:250,000 quadrangles. 

This block of mining claims is located on the northwest flank of Hahns Peak in the Hahns Peak

mining district. Relatively recent mineral resource assessments of this area were completed by

the former U.S. Bureau of Mines (Neubert, 1994) and the U.S. Geological Survey (Bankey and

others, 2000).

Geology of the area is described as “Mesozoic shale, quartzite, sandstone, and siltstone, all cut

by porphyry dikes associated with the Hahns Peak intrusion” (Neubert, 1994, p. 12). “The

Hahns Peak stock is highly altered, and silver-lead-zinc ore has been mined from the breccia

surrounding it. The stock has been explored for porphyry molybdenum and disseminated gold

deposits” (Neubert, 1994, p. 3). With one exception, most drill holes are on the south and

southeast flanks of the peak (Casaceli, 1983). 

Segerstrom and Young (1972) and Casaceli (1983) mapped the area at 1:24,000-scale. 

Attachment D shows the Segerstrom and Young (1972) geology. The oldest rocks exposed in

the area are Jurassic Morrison and Sundance Formations (Attachment D, unit Jms, turquoise) in

the central part of the parcel. Undifferentiated on the map, they consist of varicolored claystone

and shale, yellowish to red-brown sandstone, and minor thin beds of limestone. Those

exposures are nearly surrounded by Cretaceous Dakota Sandstone (Attachment D, unit Kd, olive

green), a light-gray sandstone with minor dark-gray shale beds and a basal chert-pebble

conglomerate. Cretaceous Mancos Shale (Attachment D, unit Km, mint green), dark-gray,

calcareous, and locally fossiliferous, is the dominant rock-type exposed at the northwestern

margin of the parcel. Most of the southeastern part of the parcel is in the 10-12 Ma composite

intrusion of dikes, breccia, and altered quartz latite and latite porphyry (Attachment D, units Tp

and Tpa, pink). Lithologies include late-stage quartz latite porphyry dikes, a pyroclastic base

surge deposit, alternating beds of lapillistone and tuff comprising a vent complex, multilithic

breccia, apatite dikes, monolithic intrusive breccia, and various latite porphyries. Quaternary

landslide and colluvial deposits are exposed on the southwest and northern parts of the parcel.

The Royal Flush mine includes many or most of the claims comprising Parcel A, and is the most

extensive mine in the area with more than 2,300 feet of workings on two levels (Neubert, 1994;

Casaceli, 1983). In its early years, at 1909 prices, the mine produced “200 tons of ore averaging

$90 per ton in silver and lead” (Neubert, 1994). In the mid-1930s it produced 100 tons of ruby

silver and galena ore from gouge seams containing 3,100 g gold, 248 kg silver, 20 kg copper,

and 160 kg lead (Neubert, 1994, p. 12). 

19
C:\...\locmin\locmin79.wpd 2 August 20, 2004

The Tom Thumb mine, immediately south of Parcel A, was a silver mine that produced 200 tons

of galena-rich ore (Casaceli, 1983, p. 7). An “assay of 18,000 lbs [9 tons] of ore contained 52

oz/ton silver, 2 oz/ton gold, and 51.8 percent lead” (Gale, 1906; Casaceli, 1983). 

In recent years, the area has been explored for porphyry molybdenum by W. Bowes of

Steamboat, and by the former Anaconda Mining Company (Casaceli, 1983, Neubert, 1994).

Gold placers within 1⁄2 to 2 mi. south of Parcel A at Ways Gulch and Deep Creek produced some

gold between the 1860s to 1941 and have produced only sporadically since that period. The

value of production is estimated to be about $500,000, mostly before 1909 (Neubert, 1994, p.

11-12). 

With the exception of the Royal Flush mine, most of the production in the Hahns Peak mining

district came from mines to the south of Parcel A. 

A mineral resource assessment of this area was covered in the Routt National Forest mineral

resource assessment at a scale of 1:250,000 (Soulliere and Toth, 2000). Parcel A is within an 

area (A1) assigned high potential (where available information gives a good indication of the

level of mineral resource potential) for stockwork molybdenum type deposits including

molybdenum, copper, lead, zinc, silver, and gold. Parcel A is also within an area (C2 )assigned

high potential for polymetallic vein deposits containing lead, zinc, silver, and molybdenum. 

Areas of moderate and high gold placer potential are to the north and south of the parcel,

respectively. Mineral resource potential of Parcel A for silver-lead-zinc, molybdenum, and

placer gold is high; however, presence of an economic deposit has not been proven. 

Parcel B. Kebler Pass Wetlands

Mount Axtell 1:24,000, Paonia 1:100,000, Montrose 1:250,000 quadrangles. 

Gaskill and others (1987) mapped the area at 1:24,000 scale (Attachment E). The northern part

of the Oligocene Mount Axtell laccolith ranges from granodiorite to quartz monzonite and

quartz latite (Attachment E, unit Tp, pink). These lithologies are gradational with the

granodiorite mapped in the southern part of the laccolith. The wetlands from Kebler Pass and

along Coal Creek are in Quaternary deposits. Pleistocene glacial deposits (Attachment E, unit

Qmy, yellow with tiny orange circles) are in the valley bottom with Holocene alluvial deposits

(Attachment E, unit Qa, pale yellow) along the stream. There are several local debris and

alluvial fan deposits (Attachment E, unit Qf, yellow with speckles) and talus deposits

(Attachment E, unit Qt, medium yellow).

The parcel is located on the southernmost edge of the Ruby mining district (Wilson and others,

2000; Wilson and Spanski, 2004). However, most of the mining activity in the district was

concentrated about 1 1⁄2 mi to the north at the Forest Queen and associated mines. Most mines in

the district are in small polymetallic vein and replacement-type deposits. No mines, prospects,

or occurrences are located in the parcel, although there are several claims in the general area.

20
C:\...\locmin\locmin79.wpd 3 August 20, 2004

At a scale of 1:250,000, all of the area is permissive for the occurrence of polymetallic vein

deposits, and most of the area may also be classified as “favorable” because it is within 3 km of

a deposit or of a mineralized area containing polymetallic vein or polymetallic replacement

deposits (Wilson and others, 2004a, b). Parcel B appears to be just outside the areas assigned

any potential for polymetallic replacement deposits (Wilson and others, 2004b). Mineral

resource potential of the Kebler Pass Wetlands parcel is moderate.

Federal Lands

Selected Federal Parcel 1

Clark, Floyd Peak, Rocky Peak, and Mad Creek 1:24,000, Walden 1:100,000, Craig 1:250,000

quadrangles. 

Geologic mapping by Snyder (1980) indicates that the Federal Parcel is centered on a small

basin exposing Miocene Browns Park Formation surrounded by Lower Cretaceous Dakota

Sandstone and moving outward to upper Morrison Formation, a thin rim of Upper and Middle

Jurassic Sundance Formation and Upper Triassic Chinle Formation, to Triassic and Permian(?)

Chugwater, Red Peak Member, and Satanka(?) Formations. These Phanerozoic units are

surrounded by Paleoproterozoic (X) felsic gneiss to amphibolite metavolcanics.

At 1:250,000 scale the parcel is in an area assigned moderate potential (area D2, Attachment F)

for massive sulfides including lead, zinc, silver, copper, and gold (Soulliere and Toth, 2000). 

These deposits are found in Proterozoic calc–silicate and hornblende gneiss, amphibolite, and

felsic gneiss units. However, most of the parcel is in the Phanerozoic rocks, and only the very

periphery is in Proterozoic rocks. No productive mines or developed prospects for massive

sulfides exist in the vicinity (Wilson, 2003). The nearest claim is located about 5 km north

northeast of the parcel. Therefore, the mineral resource potential of this tract is considered to be

low.

REFERENCES:

Bankey, Viki, Soulliere, S.J., and Toth, M.I., eds., 2000, Mineral resource potential and geology

of the Routt National Forest and the Middle Park Ranger District of the Arapaho

National Forest, Colorado: U.S. Geological Survey Professional Paper 1610, 117 p.

Casaceli, R.J., 1983, The geology and mineral potential of the Hahns Peak intrusive porphyry,

Routt County, Colorado: Corvallis, Oregon State University Master’s thesis, 223 p.

Gale, H.S., 1906, The Hahns Peak gold field, Colorado: U.S. Geological Survey Bulletin 285-A,

p. 28-34.

Gaskill, D.L., DeLong, J.E., Jr., and Cochran, D.M., 1987, Geologic map of the Mt. Axtell

quadrangle, Gunnison County, Colorado: U.S. Geological Survey Geologic quadrangle

Map GQ-1604, scale 1:24,000.

21
C:\...\locmin\locmin79.wpd 4 August 20, 2004

Neubert, J.J., 1994, Mineral appraisal of Routt National Forest, Colorado: U.S. Bureau of Mines

Mineral Land Assessment Open-File Report MLA 13-94, 64 p. (plus appendices).

Segerstrom, K., and Young, E.J., 1972, General geology of the Hahns Peak and Farwell

Mountain quadrangles, Routt County, Colorado: U.S. Geological Survey Bulletin 1349,

63 p.

Snyder, G.L., 1980, Geologic map of the central part of the northern Park Range, Jackson and

Routt Counties, Colorado: U.S. Geological Survey Miscellaneous Investigations Series

I-1112, scale 1:48,000.

Soulliere, S.J., and Toth, M.I., 2000, Mineral Resources–Locatable minerals, in Bankey, Viki,

Soulliere, S.J., and Toth, M.I., eds., Mineral resource potential and geology of the Routt

National Forest and the Middle Park Ranger District of the Arapaho National Forest,

Colorado: U.S. Geological Survey Professional Paper 1610, 117 p.

Wilson, A.B., 2003, Databases and simplified geology for mineralized areas, claims, mines and

prospects in Colorado: U.S. Geological Survey Open-File Report 03-090, CD-ROM. 

URL: http://pubs.usgs.gov/of/2003/ofr-03-090/

Wilson, A.B., and Spanski, G.T., 2004, Distribution of mines and mineralized areas, in Bankey,

Viki, ed., Resource potential and geology of the Grand Mesa, Uncompahgre, and

Gunnison (GMUG) National Forests and vicinity, Colorado: U.S. Geological Survey

Bulletin 2213, Chapter E, p. 67-86. URL: http://pubs.usgs.gov/bul/2213/

Wilson, A.B., Nash, J.T., Spanski, G.T., Bankey, Viki, and Smith, S.M., 2004a, Mineral

resource assessment for polymetallic vein deposits, in Bankey, Viki, ed., Resource

potential and geology of the Grand Mesa, Uncompahgre, and Gunnison (GMUG)

National Forests and vicinity, Colorado: U.S. Geological Survey Bulletin 2213,

Chapter J, p. 150-163. URL: http://pubs.usgs.gov/bul/2213/

Wilson, A.B., Spanski, G.T., Bankey, Viki, and Smith, S.M., 2004b, Mineral resource

assessment for polymetallic replacement deposits, in Bankey, Viki, ed., Resource

potential and geology of the Grand Mesa, Uncompahgre, and Gunnison (GMUG)

National Forests and vicinity, Colorado: U.S. Geological Survey Bulletin 2213,

Chapter K, p. 164-176. URL: http://pubs.usgs.gov/bul/2213/

Wilson, A.B., Spanski, G.T., Crane, M.J., and Woodard, M.D., 2000, Databases and spatial data

model for mineralized areas, mines, and prospects in the Grand Mesa, Uncompahgre, and

Gunnison (GMUG) National Forests, Colorado: U.S. Geological Survey Open-File

Report 00-298, CD-ROM. URL: http://pubs.usgs.gov/of/2000/ofr-00-0298/

22
C:\...\locmin\locmin79.wpd 5 August 20, 2004

LIST OF ATTACHMENTS:

A. Report request (provided by USDA Forest Service).

B. Exhibit A. Legal description of non-Federal land considered in this exchange (provided

by USDA Forest Service).

C. Exhibit B. Legal description of Federal land considered in this exchange (provided by

USDA Forest Service).

D. Geology of the Hahns Peak area (from Segerstrom and Young, 1972).

E. Geology of the Kebler Pass Wetlands area (from Gaskill and others, 1987).

F. Simplified geology and resource potential of the Federal Parcel (from Soulliere and Toth,

2000).

23
C:\...\locmin\locmin79.wpd 6 August 20, 2004

Attachment A. Report request (provided by U.S. Forest Service)

24
C:\...\locmin\locmin79.wpd 7 August 20, 2004

Attachment B. Exhibit A (provided by U.S. Forest Service)

25
C:\...\locmin\locmin79.wpd 8 August 20, 2004

26
C:\...\locmin\locmin79.wpd 9 August 20, 2004

27
10

Attachment C. Exhibit B (provided by U.S. Forest Service).

28
Hahns Peak

Attachment D. Geology of the Hahns Peak area (from Segerstrom and Young, 1972). 

Area of interest shown in red. Hahns Peak mineralized area outlined in blue. 

Mines and prospects from MAS (circles) and MRDS (squares) after Wilson (2003). 

Quaternary landslide deposits mostly of Dakota Sandstone; yellow with orange stipples (Ql), 

Pink stipples (Tpa), altered porphyry; pink (Tp), rhyolite, quartz latite, and rhyodacite

intrusive porphyry; yellow (Qc), Quaternary colluvium; yellow with green stipples (Qld), 

landslide deposits; mint green (Km), Cretaceous Mancos Shale; olive green (Kd), 

Cretaceous Dakota Sandstone; turquoise (Jms), Morrison and Sundance Formations.

For other units, see Segerstrom and Young (1972). More geologic detail can be found on 

Casaceli's 1983 map.

29
EUREKA, FAIRVIEW, YELLOW JACKET, G

RUBY (FLORESTA)

MOUNTAIN GEM

RUBY KING

UNKNOWN

MARVEL

DEAN NO. 1, REDBED NOS. 1 & 2

Approx. area of interenst

Ruby mineralized area

Attachment E. Geology of the Kebler Pass Wetlands area (from Gaskill and others, 1987).

Non-Federal Parcel and wetlands area shown in red patterns. Blue outlines Ruby mineralized area. 

Mines and prospects from MAS (circles) and MRDS (squares) after Wilson (2003). 

30
Attachment F. Simplified geology and resource potential of the Selected Federal

Parcel (after Soulliere and Toth, 2000). Area of interest shown in red. 

Early Proterozoic (Xfh), Triassic to Pennsylvanian sedimentary rocks (TrPu), 

Jurassic sedimentary rocks (Ju), Cretaceous sedimentary rocks (Ku). 

13

31
C:\...\locmin\locmin76.wpd March 24, 2003

LOCATABLE MINERAL REPORT FOR THE

ROUND HILL (City and County of Denver) EXCHANGE OFFER,

PIKE AND SAN ISABEL NATIONAL FORESTS,

DOUGLAS, HUERFANO, AND PARK COUNTIES, COLORADO

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

March 24, 2003

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author.

32
C:\...\locmin\locmin76.wpd March 24, 2003

U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

(303) 236-5593

FAX (303) 236-3200

awilson@usgs.gov

March 24, 2003

Mr. M. M. Underwood

Director, Physical Resources

U.S. Forest Service

PO Box 25127

Lakewood, CO 80225-0127

Dear Mr. Underwood:

This report is in response to your February 20 request for information on locatable mineral

resources in a land exchange proposal in which the City and County of Denver, acting by and

through its Board of Water Commissioners, has offered certain non-Federal lands within the

Pike and San Isabel National Forests in exchange for Federal lands also within the Pike and San

Isabel National Forests. 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in Exhibits

A and B, which were included with your request. These lands comprise approximately 1,150

acres in Douglas, Huerfano, and Park Counties, Colorado.

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: W.C. Day

E.A. du Bray

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin76.wpd 1 March 24, 2003

For the legal location description of lands considered for exchange, refer to Exhibits A and B in

Attachment A. The report request is Attachment B. Attachments C and D are simplified

geologic maps showing the location of the Federal and Non-Federal parcels.

Non-Federal Lands

Parcel A-1 “Round Hill Parcel”

Fairplay West 1:24,000, Leadville 1:100,000, Leadville 1:250,000 quadrangles. 

The Round Hill parcel is east of Twelvemile Creek on the west flank and up to the summit of

Round Hill. Mapped (Tweto, 1974; Tweto and others, 1978) as Pennsylvanian “Minturn and

Belden Formations and related rocks”, described as “gray and red sandstone, grit, and

conglomerate, black shale, and locally abundant gypsum. Thickness as much as 9,000 (?) feet.” 

May be overlain, especially at the lower elevations, by “older glacial drift” (Pleistocene–pre-Bull

Lake) and by glacial drift (Pleistocene–Pinedale and Bull Lake).”

No mines, prospects, occurrences, or mining districts are in the vicinity. Mineral resource

potential for locatable commodities is low.

 

Parcel A-2 “Harrington Ranch Parcel”

Garo 1:24,000, Bailey 1:100,000, Denver 1:250,000 quadrangles.

Harrington Ranch parcel, in the extreme southwest corner of the Garo 1:24,000, Bailey

1:100,000, and Denver 1:250,000 quadrangles, is mapped as the evaporate-bearing facies of the

middle Pennsylvanian Minturn Formation. It is described as “gray shale, limestone, siltstone,

sandstone, white silty limestone, anhydrite, and gypsum in southwest corner of mapped area. 

Flowage makes original thickness uncertain.” [More detailed mapping may be available in a

thesis by Efraim Lozano, 1965, Geology of the southwestern Garo area, South Park, Park

County, Colorado: Colorado School of Mines MS thesis, 115 p. This thesis could not be

obtained in timely fashion for this report.]

No mines, prospects, occurrences, or mining districts are in the vicinity. Mineral resource

potential for locatable commodities is low.

Parcel A-3 “Westcreek Parcel”

Westcreek 1:24,000, Bailey 1:100,000, Denver 1:250,000 quadrangles. 

Both parts of the parcel are mapped in the main body of the Pikes Peak batholith. 

The only geologic mapping is the Denver 1o X 2o

 quadrangle at 1:250,000-scale (Bryant and

others, 1981). This map shows that the Northwestern Lode, in section 23, is in fine-grained

granite (unit Ypf) which is described as “pink fine-grained equigranular biotite granite.” The

part of the parcel in section 26 is in the “pink to reddish medium- to coarse-grained, biotite or

hornblende-biotite granite” (unit Ypp), the predominant rock type of the batholith. The small

pluton at Thunder Butte (unit Ys), also part of the main body of the Pikes Peak batholith, is

34
C:\...\locmin\locmin76.wpd 2 March 24, 2003

syenite described as “light-tan to gray-green, fine- to coarse-grained syenite, quartz syenite and

leucosyenite, locally containing ferrohastingsite, fayalite, and hedenbergite.”

Although the Northwestern Lode is a patented lode claim, there is no indication as to what type

of deposit or commodity is there. By definition, at the time of patent, the claimant had to prove

the existence of a valuable resource. Approximately 1/2 mile to the northwest, on the west flank

of Thunder Butte, there is an unnamed occurrence of molybdenum (MAS 80357021, MRDS

D010565). No other information about the site is available. Because the claim was patented,

there is some chance that there is moderate potential for a locatable mineral deposit, but because

it appears that it was never developed, the resource potential is probably not high. No other

mines, prospects, occurrences, or mining districts are in the vicinity.

Parcel A-4 “Huerfano Claims”

Blanca Peak 1:24,000, Blanca Peak 1:100,000, Trinidad 1:250,000 quadrangles. 

This group is described in 3 separate blocks: 1) Coronado Millsite, 2) Hawkins and Eagle Plume

Lodes, and 3) Highline, Coronado, Copper King, Victor, Slide, Pilot, Skyscraper, and Ariel

Lodes. All of the geologic descriptions that follow for these claims are based on the geologic

mapping by Johnson and Bruce (1991).

Coronado Millsite is in Huerfano Creek and is mapped as Quaternary alluvium overlying Early

Proterozoic tonalite gneiss. Hawkins and Eagle Plume Lodes are oriented north-northwesterly

on the northeast flank of Blanca Peak parallel to, and possibly along, some of the many high

angle faults in the area. The Hawkins Lode appears to follow a Proterozoic basaltic or gabbroic

dike in Early Proterozoic white to light-gray-green, buff-weathering, homogeneous tonalite

gneiss. Eagle Plume lode may straddle the faults that separate the tonalite gneiss on the east

from dark-gray to very dark green Early Proterozoic metagabbro. The Highline-Coronado block

is also in the Early Proterozoic metagabbro, but here it is cut by northeast-striking Miocene or

Oligocene felsic (granitic) dikes. 

The claim shapes near the center of the Blanca mining district indicate that these claims were

patented. A millsite in Huerfano Creek indicates that the area did produce some ore. A mine

labeled “McMillan Group” in both MRDS and MAS/MILS plots at the Eagle Plume Lode

(Wilson, 2003). Supposedly, the McMillan (MRDS D006754, MAS 80557014) was developed

for gold, silver, bismuth, copper, and tellurium. It is classified as an inactive prospect with a

crosscut tunnel and a 40 ton concentrating mill. The millsite in Huerfano Creek may be this one. 

The McMillan deposit is described as tabular with the ore materials sylvanite(?),

tellurobismuthite, and hessite (MRDS D006754). The Coronado-Highline Group (MRDS

D010569, MAS 80557017), closer to the summit of Blanca Peak, was exploited for copper, gold,

silver, and tellurium from chalcopyrite and unknown gold and silver minerals. These veins were

developed by a 120-ft tunnel with 60-ft raise, and 184 ft, 75 ft, and 50 ft crosscuts. Eagle Plume

Lode is listed in the MRDS description as an unpatented claim. Mineral resource potential for

this area is high; however it is not expected that the area contains an economically significant

deposit.

35
C:\...\locmin\locmin76.wpd 3 March 24, 2003

Federal Lands

“Elevenmile Parcel”

Elenvenmile Canyon 1:24,000, Pikes Peak 1:100,000, Pueblo 1:250,000 quadrangles. 

The Elevenmile parcel is at the eastern edge of Elevenmile Canyon Reservoir. The area is

mapped (Wobus and Epis, 1978) as Mesoproterozoic quartz monzonite (Yem) of Elevenmile

Canyon and is dated at 1,460 Ma by Rb-Sr. This unit is described as “mottled pink and darkgray, medium-grained, porphyritic biotite quartz monzonite; massive to weakly foliated with

pink subhedral microcline crystals [...] set in a biotite-rich groundmass.” Smaller areas of the

parcel are underlain by Mesoproterozoic quartz monzonite (unit Yqm, approximately 1.45 Ga)

that is light-tan to pink, fine- to medium-grained muscovite-biotite quartz monzonite. The

quartz monzonite (Yqm) is correlated with the Silver Plume Quartz Monzonite of the central

Front Range. Also mapped in the area is Paleoproterozoic granodiorite (Xgd). Estimated to be

1.7 Ga, this unit is “pink to gray, medium- to coarse-grained biotite [or] biotite-hornblende

granodiorite that is correlated with the Boulder Creek Granodiorite of the Central Front Range”

(Wobus and Epis, 1978).

The nearest mineral deposit is an unnamed and little developed producer of barite, located

approx. 3/4 mile to the northwest at Caylor Gulch (MRDS D004860, MAS 80930072). No other

mines, prospects, occurrences, or mineral districts are in the vicinity. Mineral resource potential

for locatable commodities is expected to be low.

36
C:\...\locmin\locmin76.wpd 4 March 24, 2003

REFERENCES:

Green, G.N., 1992, The digital geologic map of Colorado in ARC/INFO format: U.S.

Geological Survey Open-File Report 92-507.

Johnson, B.R., and Bruce, R.M., 1991, Geologic map of parts of the Twin Peaks and Blanca

Peak quadrangles, Alamosa, Costilla, and Huerfano Counties, Colorado: U.S. Geological

Survey Miscellaneous Field Studies Map MF-2169, scale 1:24,000.

Lozano, Efraim, 1965, Geology of the southwestern Garo area, South Park, Park County,

Colorado: Colorado School of Mines M.S. thesis, 115 p.

Tweto, Ogden, 1974, Reconnaissance geologic map of the Fairplay West, Mount Sherman,

South Peak, and Jones Hill 7-1/2 minute quadrangles, Park, Lake, and Chaffee Counties,

Colorado: U.S. Geological Survey Miscellaneous Field Studies Map MF-555, scale

1:62,500.

Tweto, Ogden, 1979, Geologic map of Colorado: U.S. Geological Survey Special Geologic

Map, scale 1:500,000.

Tweto, Ogden, Moench, R.H., and Reed, J.C., Jr., 1978, Geologic map of the Leadville 1o

X 2o

quadrangle, northwestern Colorado: U.S. Geological Survey Miscellaneous

Investigations Series Map I-999, scale 1:250,000.

Wilson, A.B., 2003, Databases and simplified geology for mineralized areas, claims, mines and

prospects in Colorado: U.S. Geological Survey Open-File Report 03-090.

Wobus, R.A., and Epis, R.C., 1978, Geologic map of the Florissant 15-minute quadrangle, Park

and Teller Counties, Colorado: U.S. Geological Survey Miscellaneous Investigations

Series Map I-1044, scale 1:62,500.

LIST OF ATTACHMENTS:

A. Exhibits A and B. Legal description of Non-Federal and Federal land considered in this

exchange (provided by U.S. Forest Service).

B. Report request (provided by U.S. Forest Service).

C. Simplified geologic map showing location of Federal parcel and non-Federal parcels A-1

to A-3. (After Tweto, 1979; Green, 1992; Wilson, 2003) .

D. Simplified geologic map showing location of non-Federal parcels A-1 to A-3. (After

Tweto, 1979; Green, 1992; Wilson, 2003).

37
C:\...\locmin\locmin76.wpd 5 March 24, 2003

Attachment A. Exhibits A and B (provided by U.S. Forest Service)

38
C:\...\locmin\locmin76.wpd 6 March 24, 2003

Attachment B. Report request (provided by U.S. Forest Service).

39
C:\...\locmin\locmin76.wpd 7 March 24, 2003

Attachment C. Simplified geologic map showing location of Federal parcel and non

parcels A-1 to A-3. (After Tweto, 1979; Green, 1992; Wilson, 2003).

40
C:\...\locmin\locmin76.wpd 8 March 24, 2003

Attachment D. Simplified geologic map showing location of non-Federal parcel A-4

Tweto, 1979; Green, 1992; Wilson, 2003).

41
C:\...\locmin\locmin81.wpd September 30, 2004

LOCATABLE MINERAL REPORT FOR THE

LAUGHLIN PARK (Smith) LAND EXCHANGE OFFER,

SAN JUAN AND PIKE/SAN ISABEL NATIONAL FORESTS,

ARCHULETA, CHAFFEE, AND EAGLE COUNTIES, COLORADO

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

September 30, 2004

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author.

42
C:\...\locmin\locmin81.wpd September 30, 2004

U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

(303) 236-5593

awilson@usgs.gov

September 30, 2004

Mr. Randall Karstaedt

Director, Physical Resources

U.S. Forest Service

P.O. Box 25127

Lakewood, CO 80225-0127

Dear Mr. Karstaedt:

This report is in response to your August 12 request for information on locatable mineral

resources in a land exchange proposal in which Thomas H. And Margie E. Smith have offered

certain non-Federal lands within the San Juan and Pike/San Isabel National Forests in exchange

for Federal lands within the San Juan National Forest. 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in Exhibits

A and B, which were included with your request. These lands comprise approximately 594 acres

in Archuleta, Chaffee, and Eagle Counties, Colorado.

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: C.J. Nutt

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin81.wpd 1 September 30, 2004

For the legal location description of lands considered for exchange, refer to Exhibits A and B in

Attachments A and B. The report request is Attachment C. Attachments D and E are simplified

geologic maps showing the approximate locations of the Federal and non-Federal parcels.

Non-Federal Lands

Parcel A “Laughlin Park”

Jackson Mountain 1:24,000, Chromo 1:62,500, Antonito 1:100,000, Durango 1:250,000

quadrangles. 

The Laughlin Park parcel is east of Jackson Mountain (Attachment D). There does not appear to

be any detailed geologic mapping available for this area; the only geologic map is the Durango

1:250,00-scale map (Steven and others, 1974). Although the parcel is entirely contained within

Tertiary intrusive rock (intermediate to felsic composition, approx. 40-20 Ma), it does not appear

that any mineralization is associated with the intrusion (Van Loenen and Gibbons, 1997, p. 27). 

Mapping does not reveal the form of the intrusion.

There are no mines or prospects in the vicinity (Wilson, 2003) nor are there any associated with

the intrusion. Due to lack of geologic indications of mineralization, the resource assessment of

the San Juan National Forest did not include this parcel in the area deemed “favorable” for

mineral resource potential (Van Loenen and Gibbons, 1997). Therefore, mineral resource

potential for locatable minerals is considered to be low.

 

Parcel B “Spiler Canyon”

Serviceberry Mountain and Edith 1:24,000, Antonito 1:100,000, Durango 1:250,000 quadrangles.

The Spiler Canyon parcel is between 1-1/2 and 2 mi east of Blanca. There does not appear to

be any detailed geologic mapping available in this area; the only geologic map is the Durango

1:250,00-scale map (Steven and others, 1974, Attachment D). Most of the parcel is in Upper

Cretaceous Mesaverde Formation, an interbedded thin sandstone and dark-gray clay shale

(Steven and others, 1974). The extreme northeast edge of the parcel may be cut by a northweststriking fault. Exposed to the northeast of the fault is Upper Cretaceous Lewis Shale, a dark-gray

shale containing thin sandstone beds near the top, and rusty-weathering concretions in the lower

part (Steven and others, 1974). Where not in fault contact, Lewis Shale overlies the Mesaverde

Formation, but the exact relationships are not indicated on the map.

There are no mines or prospects in the vicinity (Wilson, 2003). Based on lack of indication of

mineralization, the resource assessment of the San Juan National Forest did not include the area

surrounding this parcel in an area of “favorable” mineral resource potential (Van Loenen and

Gibbons, 1997). Therefore, mineral resource potential for locatable minerals is considered to be

low.

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Parcel C “Chaffee County Mining Claims”

Mt. Elbert 1:24,000, Leadville 1:100,000, Leadville 1:250,000 quadrangles. 

The claims in this parcel are located near the head of Willis Gulch in the main body of the

Twin Lakes pluton (Attachment E). The pluton is Paleocene and primarily composed of

porphyritic biotite granodiorite (Fridrich and others, 1998; Tweto and others, 1978). Early

Proterozoic Kroenke Granodiorite crops out in the area, and there are local Quaternary surficial

deposits. Note that the locations of the claims shown in Attachment C are approximate.

Several molybdenum prospects in the vicinity, as well as the claims in the parcel, are outside of

known productive mining districts (Wilson, 2003). The parcels are a little more than 1 mi

northwest of the Winfield district and about 3 1⁄2 mi south of the Twin Lakes district. The

resource assessment of the San Isabel National Forest places this area in a geologic terrane that

was assigned high mineral resource potential with certainty level C (moderately high certainty)

for disseminated and stockwork deposits in plutonic rocks containing molybdenum and copper

(Taylor and others, 1984). Certainty was established based on data that suggest the presence of a

geologic environment with resource potential, but without enough data to establish that resourceforming processes had occurred. By virtue of these being patented mining claims, at the time

the patent was granted the claim was judged to be economically viable. However, lack of

productive mines in the immediate vicinity would suggest that any deposit that may occur in this

area is currently subeconomic.

Federal Lands

“Job Corps/Oak Brush Hill”

Pagosa Springs 1:24,000, Durango 1:100,000, Durango 1:250,000 quadrangles. 

Most of the Job Corps/Oak Brush Hill parcel is mapped (Hail, 1971; Steven and others, 1974,

Attachment D) as the lower part of the Upper Cretaceous Mancos Shale. The western part of the

parcel is mapped as Lower Cretaceous Dakota Sandstone and Burro Canyon Formation,

undifferentiated. The Dakota disconformably overlies the Burro Canyon. Dakota Sandstone is

described as light gray to brown sandstone with interbedded siltstone and carbonaceous shale,

commonly with a chert-pebble conglomerate or conglomeratic sandstone at the base. The Burro

Canyon Formation is lenticular chert-pebble conglomerate and green and gray claystone. 

The area immediately to the south of the parcel (Oak Grove Ranch) was prospected for optical

calcite in the 1930s and 1940s. However, at this location and several others farther away

(including Seavy Ranch, Attachment D)“the calcite crystals uncovered at the surface and in pits,

trenches, and shafts were found to be unsuitable for optical purposes because of fracturing and

color in the crystals” (Deshayes and Wilson, 1949, p. 2). Based on lack of indication of

mineralization, the resource assessment of the San Juan National Forest did not include the area

surrounding this parcel in an area of “favorable” mineral resource potential (Van Loenen and

Gibbons, 1997). Therefore, mineral resource potential for locatable minerals is considered to be

low.

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“Dutton”

Pagosa Springs 1:24,000, Durango 1:100,000, Durango 1:250,000 quadrangles. 

Only 1/4 mi to the north of the Job Corps/Oak Brush Hill parcel, the Dutton parcel is entirely in

Mancos Shale (Attachment D). The southwest half of this parcel is in the lower part of the

formation, the northeast half is in the upper part of the formation. 

Based on lack of indication of mineralization, the resource assessment of the San Juan National

Forest did not include the area surrounding this parcel in an area of “favorable” mineral resource

potential (Van Loenen and Gibbons, 1997). Therefore, mineral resource potential for locatable

minerals is considered to be low.

REFERENCES:

Deshayes, E.V., and Wilson, S.R., 1949, Investigation of Colorado Minerals Co. calcite deposits,

Archuleta and Hinsdale Counties, Colo[rado]: U.S. Bureau of Mines Report of

Investigations 4554, 7 p.

Fridrich, C.J., DeWitt, Ed, Bryant, Bruce, Richard, Steve, and Smith, R.P., 1998, Geologic map

of the Collegiate Peaks Wilderness Area and the Grizzly Peak Caldera, Sawatch Range,

central Colorado: U.S. Geological Survey Miscellaneous Investigations Series Map I2565, scale 1:50,000.

Hail, W.J., Jr., 1971, Geologic reconnaissance map of the Chris Mountain and Pagosa Springs

quadrangles, Archuleta County, Colorado: U.S. Geological Survey Open-File Report 71-

142.

Steven, T.A., Lipman, P.W., Hail, W.J., Jr., Barker, Fred, and Luedke, R.G., compilers, 1974,

Geologic map of the Durango quadrangle, southwestern Colorado: U.S. Geological

Survey Miscellaneous Investigations Series Map I-764, scale 1:250,000.

Tweto, Ogden, Moench, R.H., and Reed, J.C., Jr., 1978, Geologic map of the Leadville 1o

X 2o

quadrangle, northwestern Colorado: U.S. Geological Survey Miscellaneous

Investigations Series Map I-999, scale 1:250,000.

Van Loenen, R.E., and Gibbons, A.B., 1997, Mineral resource potential and geology of the San

Juan National Forest, Colorado: U.S. Geological Survey Bulletin 2127, 140 p.

Wilson, A.B., 2003, Databases and simplified geology for mineralized areas, claims, mines and

prospects in Colorado: U.S. Geological Survey Open-File Report 03-090.

46
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LIST OF ATTACHMENTS:

A. Exhibit A. Legal description of non-Federal land considered in this exchange (provided

by U.S. Forest Service).

B. Exhibit B. Legal description of Federal land considered in this exchange (provided by

U.S. Forest Service).

C. Report request (provided by U.S. Forest Service).

D. Geologic map showing location of Federal parcels and non-Federal parcels A and B and

mines and prospects. (After Steven and others, 1974; Wilson 2003).

E. Geologic map showing location of non-Federal parcel C. (After Fridrich and others,

1998; Wilson, 2003).

47
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Attachment A. Exhibit A (provided by U.S. Forest Service)

48
C:\...\locmin\locmin81.wpd 6 September 30, 2004

Attachment B. Exhibit B (provided by U.S. Forest Service).

49
C:\...\locmin\locmin81.wpd 7 September 30, 2004

Attachment C. Report Request (provided by U.S. Forest Service).

50
C:\...\locmin\locmin81.wpd 8 September 30, 2004

Attachment D. Geologic map showing location of non-Federal parcels

A and B (Laughlin Park and Spiler Canyon), and Federal parcels

(Job Corps /Oak Brush Hill and Dutton). (After Steven and

others, 1974; Wilson, 2003). Rock units of interest include: Ti,

Tertiary intrusive rocks; Kl, Upper Cretaceous Lewis Shale; Kmv,

Upper Cretaceous Mesa Verde Formation; Km, Upper Cretaceous

Mancos Shale, undivided; Kmu, Mancos Shale, upper part; Kml,

Mancos Shale, lower part; Kdb, Upper and Lower Cretaceous

Dakota Sandstone and Burro Canyon Formation.

51
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Attachment E. Geologic map showing location of non-Federal parcels

C. (After Fridrich and others, 1998; Wilson, 2003). Rock units of

interest include: Qs, Quaternary surficial deposits; Qg, Quaternary

glacial deposits; Tt, Paleocene Twin Lakes Pluton, main body;

Xk, Early Proterozoic Kroenke Granodiorite; and Xd, Early

Proterozoic Denny Creek Granodiorite, main body.

52
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LOCATABLE MINERAL REPORT FOR THE

FISH CREEK LAND EXCHANGE OFFER,

SAN JUAN NATIONAL FOREST,

SAN JUAN, LA PLATA, AND DOLORES COUNTIES, COLORADO

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

April 25, 2005

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author. This report has not been reviewed for stratigraphic nomenclature.

53
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U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

303) 236-5593

awilson@usgs.gov

April 25, 2005

Mr. Randall Karstaedt

Director, Physical Resources

U.S. Forest Service

P.O. Box 25127

Lakewood, CO 80225-0127

Dear Mr. Karstaedt:

This report is in response to your February 24 request for information on locatable mineral

resources in a land exchange proposal in which Morgan Land & Cattle Partners, Ltd., and

Harvey Peel, represented by Western Land Group, have offered certain non-Federal lands within

the San Juan National Forest in exchange for Federal lands also within the San Juan National

Forest. 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in Exhibits

A and B, which were included with your request. These lands comprise approximately 120 acres

in San Juan, La Plata, and Dolores Counties, Colorado.

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: C.J. Nutt

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin88.wpd 1 April 25, 2005

For the legal location description of lands considered for exchange exclusive of Reservations,

Outstanding Rights, or other restrictions, refer to Exhibits A and B in Attachments A and B. 

The report request is Attachment C. Attachments D and E are geologic maps showing the

approximate locations of the non-Federal parcels.

Non-Federal Lands

Parcels 1 “Wall Street, Cherokee, Hailstone, and Jennie Lind lode mining claims”

Parcel 2 “Sebastapool lode mining claim, and Parcel 3 “Oregon, Emma, and Galena lode mining

claims”

Ophir 1:24,000, Silverton 1:100,000, Durango 1:250,000 quadrangles. 

All the claims in Parcels 1 and 3 are in the vicinity of Ice Lake basin, south of Ophir. The

geology was mapped (Attachment D) and the formations described by Luedke (1996) at

1:24,000-scale. Eocene Telluride Conglomerate (unit Tte) is the oldest formation exposed in

any of the parcels. The conglomerate and minor sandstone contains pebble to cobble clasts in an

arkosic and sandy matrix. Unconformably overlying the conglomerate is the Oligocene San

Juan Formation (unit Tsj) of the Sapinero Mesa Tuff. The San Juan Formation is a 210-610 mthick pile of reworked lahar or mudflow breccia intermixed with sandy tuff and tuff

conglomerate. In the vicinity of the Sebastapool claim, the San Juan Formation is extensively

hydrothermally altered. Resting on the top of the uneven erosion surface on the San Juan

Formation are flow breccias, tuffs, and flows of the Burns Member (unit Tsb) of the Silverton

Volcanics. Oligocene ash-flow tuff (unit Tt1-7) overlies the Burns Member, and in this area, it is

hydrothermally altered to quartz-sericite-clay, and locally to quartz-clay acid-sulfate minerals. 

Numerous veins or mineralized faults or fissures are present in the Burns Member and in the

ash-flow tuff. Small dikes of Oligocene dacite (unit Tid) intrude the Burns Member. 

Wall Street claim is in the Burns Member on the lowest slopes, and in hydrothermally altered

ash-flow tuff at the higher elevations. 

Hailstone claim is in the Burns Member, roughly parallel to one group of mineralized veins or

fissures and perpendicular to both dacite dikes and another mineralized vein or fissure.

Cherokee claim is in the Burns Member parallel to a mineralized vein or fissure.

Jennie Lind claim parallels a vein in the Burns Member in the underlying San Juan Formation of

the Sapinero Mesa Tuff.

Sebastapool claim is entirely in hydrothermally altered San Juan Formation.

Oregon, Emma, and Galena claims are in the Burns Member and San Juan Formations,

overlying Eocene Telluride Conglomerate.

With the exception of the Sebastapool property, all of the claims are in the Ice Lake mining

district, a description of which is in Neubert and others (1992, p. 190-196). All of the

properties are in an area assessed as being favorable for the presence of polymetallic

replacement and skarn deposits (hydrothermal deposits of Ag, Pb, Zn, and Cu sulfide minerals in

massive lenses, pipe-shaped bodies, and associated veins in limestone, dolostone, or other

soluble strata that are replaced by ore) and for Creede-type epithermal veins hosted in Tertiary

55
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volcanic terrane. Each of the patented claims has high potential for the above deposit-types. 

However, the very small size of the claims and lack of apparent mining in the area, in spite of

intense prospecting, suggests that any of these deposits would be small and likely not economic

(at current metal prices at the time of this report). Interestingly, these claims are all in an area

assigned “favorable” potential for oil and gas accumulations of the Silverton Delta play. In this

play conventional accumulations occur in permeable deltaic sandstones (that are equivalents of

the Hermosa Group) along the flank of the Paradox Basin (Van Loenen and Gibbons, 1997).

Additionally, the Sebastapool claim is in an area assessed as favorable for stockwork

molybdenum (and may also contain tin, tungsten, and bismuth) and for porphyry coppermolybdenum deposits (and may also contain Ag and Au) (Van Loenen and Gibbons, 1997).

This hydrothermally-altered area, which includes the Sebastapool claim, is known as the Mount

Moly system. It is a subeconomic ~26 Ma porphyry molybdenum (+/- copper) system with

strongly developed quartz-sericite-pyrite alteration and disseminated pyrite (D.J. Bove, USGS,

3/16/05, oral commun.).

Parcel 4 “Republic and Aztec lode mining claims”

Columbine Pass 1:24,000, Silverton 1:100,000, Durango 1:250,000 quadrangles. 

Geology in Missouri Gulch in the vicinity of the Republic and Aztec claims is mapped as 1,350

Ma ± 50 Middle Proterozoic Trimble Granite stock (Barker, 1969, p. 27-28.) (unit Ytr,

Attachment E, after Schmitt and Raymond, 1977). The Trimble Granite stock intrudes

approximately 1460 Ma Eolus Granite, which forms two composite batholiths (Barker, 1969, p.

25-27). Veins appear to be related to the hypabyssal granite (unit Tio) and rhyolite porphyry

(unit Tiy) plug and related rocks, more than a half-mile from the northern end of the claim

block, in Chicago Basin (Schmitt and Raymond, 1977; Neubert and others, 1992). The mining

claims parallel a north-northeast striking fracture or vein (Schmitt and Raymond, 1977). It is not

clear from the juxtaposition of the geologic map with the claim map if the claim follows the vein

at the surface or if the data layers are offset due to scale or projection issues (Attachment E).

The claims are in an area assessed as favorable for the presence of polymetallic veins, skarns,

and replacement deposits adjacent to stockwork molybdenum or molybdenum-mineralized

porphyry stocks (Van Loenen and Gibbons, 1997). It is also assessed as favorable for vein

uranium deposits related to 1.4 Ga and 10-Ma granites intruding Middle and (or) Early

Proterozoic rocks (Van Loenen and Gibbons, 1997). The entire Needle Mountains mining

district may have produced a total of $12,500, mostly as gold and silver values, prior to

1900. Known mines in the vicinity of the parcel with recorded production are the Eureka

($5,000), Aetna ($5,000), Pittsburgh ($2,000), and Aztec ($500) (Steven and others, 1969, p.

92). By virtue of being a patented claim, at one time this property was demonstrated to have a

viable deposit. Therefore, resource potential is high. However, it is unlikely to be economic

under current (2005) conditions.

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Federal Lands

Parcel 1NF

Clyde Lake 1:24,000, Dove Creek 1:100,000, Cortez 1:250,000 quadrangles. 

The parcel is in the Permian Cutler and Triassic Dolores Formations (Cross and Ransome, 1905;

Haynes and others, 1972). The Cutler Formation is a fluvial micaceous arkosic sandstone,

siltstone, and conglomerate; the Dolores Formation is fluvial siltstone, sandstone, and shale with

a few layers of limestone-shingle conglomerate (Haynes and others, 1972). 

The nearest prospects are more than a mile away, but little is known about them. The Little

Silver mine in Copper Gulch and the Teaser Prospect (2 miles south of the Little Silver) have

too low concentrations of base and precious metals to be considered a resource and did not

warrant an economic evaluation (Neubert and others, 1992, p. 26, 28). No resource potential for

locatable or salable minerals was identified in the entire township (Van Loenen and Gibbons,

1997).

Parcel 2NF

Baldy Mountain 1:24,000, Durango 1:100,000, Durango 1:250,000 quadrangles. 

No maps or legal description were included with the report request. However, this parcel is in

an area for which unpublished reconnaissance mapping by W.J. Hail (USGS, undated) was used

for the compilation of the Durango quadrangle (Steven and others, 1974). No other published

geologic maps with greater detail could be located. 

No favorable resource potential for any locatable commodities is indicated for the entire

township (Van Loenen and Gibbons, 1997). Therefore, resource potential for locatable minerals

is low. For leasable commodities such as coal, coal-bed gas, natural gas, and oil and gas, there is

much favorable ground in the township (Van Loenen and Gibbons, 1997). 

LIST OF ATTACHMENTS:

A. Exhibit A. Legal description of non-Federal land considered in this exchange (provided

by U.S.D.A. Forest Service).

B. Exhibit B. Legal description of Federal land considered in this exchange (provided by

U.S.D.A. Forest Service).

C. Report request (provided by U.S.D.A. Forest Service).

D. Geologic map showing approximate locations of non-Federal parcels 1-3 and the Ice

Lake mineralized area (after Luedke, 1996; Wilson, 2003 and unpublished data, 2005). 

E. Geologic map showing approximate location of Aztec and Republic claims in the Needle

Mountains mineralized area (Schmitt and Raymond, 1977; Wilson, 2003 and

unpublished data, 2005). 

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REFERENCES:

Barker, Fred, 1969, Precambrian geology of the Needle Mountains, southwestern Colorado: 

U.S. Geological Survey Professional Paper 644-A, p. 35 p.

Cross, Whitman, and Ransome, F.L., 1905, Description of the Rico quadrangle, Colorado: U.S.

Geological Survey Geologic Atlas, Folio 130, scale 1:62,500. 

Haynes, D.D., Vogel, J.D., and Wyant, D.G., compilers, 1972, Geology, structure, and uranium

deposits of the Cortez quadrangle, Colorado and Utah: U.S. Geological Survey

Miscellaneous Geologic Investigations Map I-629, scale 1:250,000.

Luedke, R.G., 1996, Geologic map of the Ophir quadrangle, San Juan, San Miguel, and Dolores

Counties, Colorado: U.S. Geological Survey Geologic Quadrangle Map GQ-1760, scale

1:24,000.

Neubert, J.T., Ellis, C.E., Hannigan, B.J., Jeske, R.E., Martin, C.M., Thompson, J.R., Tuftin,

S.E., Wood, R.H., II, and Zelten, J.E., 1992, Mineral appraisal of the San Juan National

Forest, Colorado, with a section on Industrial Minerals by Raby, A.G.: U.S. Bureau of

Mines Mineral Land Assessment Open-File Report MLA-2-92, 311 p.

Schmitt, L.J., Jr., and Raymond, W.H., 1977, Geology and mineral deposits of the Needle

Mountains district, southwestern Colorado: U.S. Geological Survey Bulletin 1434, 40 p.

Steven, T.A., Lipman, P.W., Hail, W.J., Jr., Barker, Fred, and Luedke, R.G., compilers, 1974,

Geologic map of the Durango quadrangle, southwestern Colorado: U.S. Geological

Survey Miscellaneous Investigations Series Map I-764, scale 1:250,000.

Steven, T.A., Schmitt, L.J., Jr., Sheridan, M.J., and Williams, F.E., 1969, Mineral resources of

the San Juan Primitive Area, Colorado: U.S. Geological Survey Bulletin 1261-F, 187 p.

Van Loenen, R.E., and Gibbons, A.B., 1997, Mineral resource potential and geology of the San

Juan National Forest, Colorado: U.S. Geological Survey Bulletin 2127, 140 p.

Wilson, A.B., 2003, Databases and simplified geology for mineralized areas, claims, mines and

prospects in Colorado: U.S. Geological Survey Open-File Report 03-090.

58
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Attachment A. Exhibit A–Legal description of non-Federal land considered in this

exchange exclusive of Outstanding Rights and Reservations (provided by U.S.D.A.

Forest Service).

59
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Attachment B. Exhibit B--Legal description of Federal land considered in this

exchange(provided by U.S.D.A. Forest Service).

60
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Attachment C. Report Request (provided by U.S.D.A. Forest Service).

61
C:\...\locmin\locmin88.wpd 8 April 25, 2005

Attachment D. Geologic map showing approximate locations of non-Federal

parcels 1-3 (red outlines) and the Ice Lake mineralized area (blue outline) (after

Luedke, 1996; Wilson, 2003 and unpublished data, 2005). Rock units of interest

include: Tid, Oligocene Dacite (teal); Tt1-7, Oligocene ash-flow tuff (green); Tsb,

Oligocene Burns Member of Silverton Volcanics (pink); Tsj, Oligocene San Juan

Formation (orange); and Tte, Eocene Telluride Conglomerate (violet). Mine

locations, shown as circles and squares, are from the USGS MAS and MRDS

databases, respectively (Wilson, 2003). These mine locations have not been

verified and may be unreliable. (Map scale is unknown) 

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Attachment E. Geologic map showing approximate location of Aztec and Republic

claims in the Needle Mountains mineralized area (after Schmitt and Raymond,

1977; Wilson, 2003 and unpublished data, 2005). Rock units of interest include:

Tiy, rhyolite porphyry (medium pink); Tio, granite porphyry (light pink); Ytr,

Trimble Granite (dark gray); and Ye, Eolus Granite (white). Mine and prospect

data are from the MAS (circles) and MRDS (squares) databases (Wilson, 2003).

These locations have not been verified and may be unreliable. 

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LOCATABLE MINERAL REPORT FOR THE

KENT/LINDSAY EXCHANGE OFFER,

UNCOMPAHGRE NATIONAL FOREST,

OURAY COUNTY, COLORADO

By

Anna B. Wilson

U.S. Geological Survey

January 19, 2005

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author.

64
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U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

303) 236-5593

awilson@usgs.gov

January 19, 2005

Mr. Randall Karstaedt

Director, Physical Resources

U.S.D.A. Forest Service

P.O. Box 25127

Lakewood, CO 80225-0127

Dear Mr. Karstaedt:

This report is in response to your January 13 request for information on locatable mineral

resources in a land exchange proposal in which Kelvin Kent and Rebecca Lindsay have offered

certain non-Federal lands within the Uncompahgre National Forest in exchange for Federal lands

also within the Uncompahgre National Forest. 

In accordance with the working agreement under Public Law 86-509, we are providing you with

a report on the locatable mineral resources on the lands described in Exhibits A and B, which

were included with your request. These lands comprise approximately 60.6 acres in Ouray

County, Colorado.

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: C.J. Nutt

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin86.wpd 3 January 19, 2005

The report request is in Attachment A. For the legal location description of lands considered for

exchange, exclusive of reservations and outstanding rights, refer to Exhibits A and B in

Attachment B. Attachment C is a geologic map showing the location of the exchange parcels.

Non-Federal Lands

Mt. Sneffels mining claims

Ironton 1:24,000, Silverton 1:100,000, Durango 1:250,000 quadrangles. 

The claim block is at the southern end of Imogene Basin near its head, south of Camp Bird. The

area is mapped entirely as Miocene Burns Formation (Attachment C) of the Silverton Volcanic

Group (Burbank and Luedke, 1964). The formation is described as “medium to dark thick

massive flows and flow breccias, tuffs, and fluidal-banded flows of mainly rhyodacitic

composition” (Burbank and Luedke, 1964) and is riddled with mineralized faults or fissures.

The parcel appears to be located in the San Juan mineralized area (Wilson and others, 2000;

Wilson, 2003) but outside the Sneffels and Red Mountain mining districts (Davis and Streufert,

1990). This area is included in the mineral resource assessment of the Gunnison, Uncompahgre,

and Grand Mesa (GMUG) National Forests (Bankey, 2004). Published maps for the resource

assessment are such small-scale that it is not feasible to locate the parcel precisely on them, nor

would it be advisable. The parcel is in areas assessed as favorable for granite porphyry and

granodiorite porphyry molybdenum deposits (see Silverton caldera tracts, Bove and others,

2004, p. 112, tract 4, and p. 116, tract 9), polymetallic veins (see San Juan Mountains tract,

Wilson and others, 2004a, p. 159, tract F5), and polymetallic replacement deposits (see Ouray and

San Juan West tracts, Wilson and others, 2004b, p. 172, tract F11).

Federal Lands

Kent expansion

Ouray 1:24,000, Montrose 1:100,000, Montrose 1:250,000 quadrangles. 

The sliver of land in this exchange is too small for an accurate resource appraisal. It was

difficult to locate the parcel with any certainty on a 1:24,000-scale map to compare with

known geology and mineralization. The location shown on Attachment D is approximate.

The parcel appears to be located in Pleistocene Wisconsin stage glacial drift (Luedke and

Burbank, 1962). Pleistocene and Holocene landslide deposits nearly surround the parcel

(Attachment D).

The parcel is located in the San Juan mineralized area and immediately outside the Ouray

mineralized area (Wilson and others, 2000; Wilson, 2003). The parcel is south of the Ouray

mining district (Davis and Streufert, 1990). This area is included in the mineral resource

assessment of the Gunnison, Uncompahgre, and Grand Mesa (GMUG) National Forests

(Bankey, 2004). Published maps for the resource assessment are such small scale that it is not

66
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feasible to locate the parcel precisely on them, nor would it be advisable. The parcel is on the

margin of the area assessed as favorable for granite porphyry (see Silverton caldera tract, Bove

and others, 2004, p. 112, tract 5), polymetallic veins (see San Juan Mountains tract, Wilson and

others, 2004a, p. 159, tract F5), and polymetallic replacement deposits (see Ouray and San Juan

West tracts, Wilson and others, 2004b, p. 172, tract F11).

LIST OF ATTACHMENTS:

A. Report Request (provided by U.S. Forest Service).

B. Exhibits A and B (provided by U.S. Forest Service).

C. Portion of geologic map Ironton quadrangle (Burbank and Luedke, 1964) showing

approximate location of non-Federal parcels.

D. Portion of geologic map of Ouray quadrangle (Luedke and Burbank, 1962) showing

approximate location of Federal parcel and approximate outlines of Ouray and San Juan

mineralized areas (from Wilson and others, 2000; Wilson, 2003).

67
C:\...\locmin\locmin86.wpd 5 January 19, 2005

REFERENCES:

Bankey, Viki, ed., 2004, Resource potential and geology of the Grand Mesa, Uncompahgre, and

Gunnison (GMUG) National Forests and vicinity, Colorado: U.S. Geological Survey

Professional Paper 2213.

Bove, D.J., Knepper, D.H., Jr., Bankey, Viki, Spanski, G.T., and Smith, S.M., 2004, Mineral

resource assessment for porphyry molybdenum deposits, in Bankey, Viki, ed., Resource

potential and geology of the Grand Mesa, Uncompahgre, and Gunnison (GMUG)

National Forests and vicinity, Colorado: U.S. Geological Survey Professional Paper

2213, p. 105-123.

Burbank, W.S., and Luedke, R.G., 1964, Geologic map of the Ironton quadrangle, Colorado: 

U.S. Geological Survey Geologic Quadrangle Map GQ-291, scale 1:24,000.

Davis, M.W., and Streufert, R.K., 1990, Gold occurrences of Colorado: Colorado Geological

Survey Resource Series 28, 101 p.

Luedke, R.G., and Burbank, W.S., 1962, Geologic map of the Ouray quadrangle, Colorado: 

U.S. Geological Survey Geologic Quadrangle Map GQ-152, scale 1:24,000.

Wilson, A.B., 2003, Databases and simplified geology for mineralized areas, claims, mines and

prospects in Colorado: U.S. Geological Survey Open-File Report 03-090.

[http://pubs.usgs.gov/of/2003/ofr-03-090/]

Wilson, A.B., Nash, J.T., Spanski, G.T., Bankey, Viki, and Smith, S.M., 2004a, Mineral resource

assessment for polymetallic vein deposits, in Bankey, Viki, ed., Resource potential and

geology of the Grand Mesa, Uncompahgre, and Gunnison (GMUG) National Forests and

vicinity, Colorado: U.S. Geological Survey Professional Paper 2213, p. 150-163.

Wilson, A.B., Spanski, G.T., Bankey, Viki, and Smith, S.M., 2004b, Mineral resource assessment

for polymetallic replacement deposits, in Bankey, Viki, ed., Resource potential and

geology of the Grand Mesa, Uncompahgre, and Gunnison (GMUG) National Forests and

vicinity, Colorado: U.S. Geological Survey Professional Paper 2213, p. 164-176.

Wilson, A.B., Spanski, G.T., Crane, M.J., and Woodard, M.D., 2000, Databases and spatial data

model for mineralized areas, mines, and prospects in the Grand Mesa, Uncompahgre, and

Gunnison (GMUG) National Forests, Colorado: U.S. Geological Survey Open-File

Report 00-298. 

[http://pubs.usgs.gov/of/2000/ofr-00-0298/]

68
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Attachment A. Report request (provided by U.S. Forest Service).

69
C:\...\locmin\locmin86.wpd 7 January 19, 2005

Attachment B. Exhibits A and B (provided by U.S. Forest Service)

70
C:\...\locmin\locmin86.wpd 8 January 19, 2005

Attachment C. Portion of geologic map Ironton quadrangle (Burbank

and Luedke, 1964) showing approximate location of non-Federal

parcels. Tsb, Burns Formation of the Silverton Volcanic Group.

71
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Attachment D. Portion of geologic map of Ouray quadrangle (Luedke

and Burbank, 1962) showing approximate location of Federal parcel

and approximate outlines of Ouray and San Juan mineralized areas

(from Wilson and others, 2000; Wilson, 2003). Qs, Pleistocene and

Holocene landslide deposits; Qd, Pleistocene Wisconsin-stage glacial

drift; IPh, Pennsylvanian Hermosa Formation.

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LOCATABLE MINERAL REPORT FOR THE

TELLURIDE AIRPORT LAND EXCHANGE OFFER,

UNCOMPAHGRE NATIONAL FOREST,

SAN MIGUEL COUNTY, COLORADO

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

August 25, 2005

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author. This report has not been reviewed for stratigraphic nomenclature.

73
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U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

(303) 236-5593

awilson@usgs.gov

August 25, 2005

Mr. Randall Karstaedt

Director, Physical Resources

U.S. Forest Service

P.O. Box 25127

Lakewood, CO 80225-0127

Dear Mr. Karstaedt:

This report is in response to your June 28 request for information on locatable mineral resources

in a land exchange proposal in which the Telluride Airport Authority has offered certain nonFederal lands within the Uncompahgre National Forest in exchange for Federal lands also within

the Uncompahgre National Forest. 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in Exhibits

A and B, which were included with your request. These lands comprise approximately 95.7

acres in San Miguel County, Colorado.

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: C.J. Nutt

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin89.wpd 1 August 25, 2005

For the legal location description of lands considered for exchange, refer to Exhibits A and B in

Attachment A. The report request is Attachment B. Attachments C, D, and E are geologic maps

showing the approximate locations of the non-Federal parcels.

Non-Federal Lands

Parcels 1 “Wynne Property”

Ophir 1:24,000, Silverton 1:100,000, Durango 1:250,000 quadrangles. 

The Wynne parcel is immediately west of Ophir Loop. The bedrock geology is mapped as

Upper Jurassic Morrison Formation intruded by Oligocene granodiorite (Luedke, 1996;

Attachment C). 

The parcel is at the margin of the Ophir mineralized area, the historic Iron Springs Mining

District. Although not included in the USGS mine and prospect databases (Wilson, 2003; and

A.B. Wilson, unpublished data, 2005), the parcel is a patented claim and is near other patented

lode claims, some with a history of production. Therefore, mineral resource potential for

commodities such as gold, silver, and lead is expected to be high.

Parcel 2 “Greenberg properties”

Ophir 1:24,000, Silverton 1:100,000, Durango 1:250,000 quadrangles. 

Most of the Greenberg parcel is mapped as rhyodacite tuff breccia of the Miocene(?) San Juan

Formation (Tsj, orange), which is cut by veins and mineralized fissures (red) (Burbank and

Luedke, 1966; Attachment D). 

The parcel is made up of three patented claims: Little Bessie, Modena, and Gertrude Lodes. At

the time the claims were patented, the claim holder had to demonstrate that the claimed lands

contained viable and economic mineral deposits. There is no information in the literature citing

the mineral commodities expected or produced. Proximity to the Nellie, Wasatch, Roy Johnson,

and other mines (Wilson, 2003; and A.B. Wilson, unpublished data, 2005) and the similar

geologic setting suggest that the most likely sought commodities–silver, gold, and lead–would

have been the same as on those properties: silver, gold, and lead. Therefore, mineral-resource

potential for these commodities on the Greenberg properties is high.

Federal Lands

Telluride Airport Authority

Gray Head 1:24,000, Silverton 1:100,000, Durango 1:250,000 quadrangles. 

The Airport parcel is in an area that is underlain by most of the Upper Jurassic and Upper

Cretaceous stratigraphic section (Bush and others, 1951; Attachment E). At the lowest

elevations in Deep Creek, Upper Jurassic Entrada Sandstone is exposed, overlain successively by

Wanaka Formation, the Salt Wash sandstone and Brushy Basin shale members of the Morrison

75
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Formation, and capped by Upper Cretaceous Dakota Sandstone on the plateau (Bush and others,

1951). The sedimentary rocks are cut by the N68W-trending Vanadium fault which is downthrown on the northeast. 

Mineral prospects in Deep Creek are only a few hundred feet north of the parcel. Based on the

geologic map (Bush and others, 1961), it is probable that the workings in Deep Creek explored

vein or replacement deposits directly associated with the Vanadium fault in the Wanakah

Formation. Deep Creek mine (location uncertain) may have been mined for calcium, but no

information is available. Unverified information in the MRDS and MAS databases (Wilson,

2003) suggests that the other mines in Deep Creek may be the Blue Bird, Blue Bell, Crescent

City, and(or) Lakeview. None of the references attributed to these mines contains specific

information about the mine, and no information could be located for any of these “mines”

although the databases suggest that silver was the primary commodity, and there may have been

some lead. It is unclear if the mines in Deep Creek were productive. It also is possible that this

is a case of mistaken identity. The “newMRDS” database (USGS, 2005, unpublished data)

describes the location as a placer deposit, but the publication cited (Bush and others, 1959) for

the Placerville quadrangle (to the northwest) does not appear to contain information about the

deposit. If location information is correct, the potential for small, silver replacement deposits is

high. The parcel is several miles east of the known vanadium and chromium belts (Fischer,

1968, fig. A); resource potential for these commodities is low.

LIST OF ATTACHMENTS:

A. Exhibits A and B. Legal description of land considered in this exchange (provided by

USDA Forest Service).

B. Report request (provided by USDA Forest Service).

C. Geologic map showing approximate location of the Wynne property (after Luedke, 1996;

A.B. Wilson, unpublished data, 2005). 

D. Geologic map showing approximate locations of the Greenberg properties (after Burbank

and Luedke, 1966; A.B. Wilson, unpublished data, 2005).

E. Geologic map showing approximate locations of the Airport lands adjacent to the Airport

(after Bush and others, 1961; A.B. Wilson, unpublished data, 2005).

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REFERENCES:

Burbank, W.S., and Luedke, R.G., 1966, Geologic map of the Telluride quadrangle,

southwestern Colorado: U.S. Geological Survey Geologic Quadrangle Map GQ-504,

scale 1:24,000.

Bush, A.L., Bromfield, C.S., Marsh, O.T., and Taylor, R.B., 1961, Preliminary geologic map of

the Gray Head quadrangle, San Miguel County, Colorado: U.S. Geological Survey

Mineral Investigations Field Studies Map MF-176, scale 1:24,000.

Bush, A.L., Bromfield, C.S., and Pierson, C.T., 1959, Areal geology of the Placerville

quadrangle, San Miguel County, Colorado: U.S. Geological Survey Bulletin 1072-E,

p. 295-384, scale 1:24,000.

Fischer, R.P., 1968, Vanadium deposits of the Placerville area, San Miguel County, Colorado, in

Shomaker, John, Guidebook of San Juan-San Miguel-La Plata region, New Mexico and

Colorado: New Mexico Geological Society 19th Field Conference, p. 100-103.

Luedke, R.G., 1996, Geologic map of the Ophir quadrangle, San Juan, San Miguel, and Dolores

Counties, Colorado: U.S. Geological Survey Geologic Quadrangle Map GQ-1760, scale

1:24,000.

Wilson, A.B., 2003, Databases and simplified geology for mineralized areas, claims, mines and

prospects in Colorado: U.S. Geological Survey Open-File Report 03-090.

http://pubs.usgs.gov/of/2003/ofr-03-090/

77
C:\...\locmin\locmin89.wpd 4 August 25, 2005

Attachment A. Exhibits A and B: Legal description of land considered in this

exchange (provided by U.S.D.A. Forest Service).

78
C:\...\locmin\locmin89.wpd 5 August 25, 2005

Attachment B. Report Request (provided by U.S.D.A. Forest Service).

79
VERA

DEADWOOD

CARIBOU MILL

CROWN POINT GROUP MILL

AMERICAN FRENCHMAN

FAVORITE TUNNEL

Silver Bell

Santa Cruz mine

Badger mine

Lookout tunnel Crown Point mine

Montezuma mine

Carribeau mine

Osceola mine

Gertrude

Gold Crown

Suffolk mine

TWENTIETH CENTURY CLAIM

Single Standard

Gold King mine

BLACK WARRIOR

CREVE COEUR

GOLD RUN DUMP

IDA SHAFT

L

SILVER KING

SUFFOLK

OPHIR

Carbonates mine

Swedes mine

Dolores mine

L

Globe

Grand View Mohawk

Red Jacket

Wynne parcel

Approx. extent of Ophir mineralized area

80
HAPPY HOME

Palmyra mine

Silver King mine

Turkey Creek mine

Lakeview mine

Grand View

Mohawk

Roy Johnson mine

Mountain Quail mine

Single Standard

Highline mine

El Paso mine

Illinois tunnel

Little Joe Mine

Wasatch mine (topo)

Nellie mine

SLIDE GROUP

COLOR

Greenberg Proper

81
DEEP CREEK MINE

BLUE BELL

DEEP CREEK PLACER

WILLOW CREEK BAR (PLACER)

BLUE BIRD MINE

Approximate location of 

Airport parcel

82
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LOCATABLE MINERAL REPORT FOR THE

SOUTH GAME CREEK (VAIL CORPORATION) EXCHANGE,

WHITE RIVER NATIONAL FOREST,

EAGLE COUNTY, COLORADO

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

December 1, 2004

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author.

83
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U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

(303) 236-5593

FAX (303) 236-3200

awilson@usgs.gov

January 14, 2005

Mr. Randall Karstaedt

Director, Physical Resources

U.S. Forest Service

PO Box 25127

Lakewood, CO 80225-0127

Dear Mr. Karstaedt:

This report is in response to your November 4 request for information on locatable mineral

resources in a land exchange proposal in which the Vail Corporation has offered certain nonFederal lands within the White River National Forest in exchange for Federal lands, also within

the White River National Forest. 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in Exhibits

A and B, which were included with your request. These lands comprise approximately 615 acres

in Eagle County, Colorado.

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: C.J. Nutt

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin83.wpd 1 December 1, 2004

The report request is Attachment A (provided by the U.S. Forest Service). Refer to Attachment

B for the location description of lands considered for exchange. (For simplicity, land

reservations, outstanding rights, and other exclusions listed in Exhibits A and B provided by the

U.S. Forest Service are not included in Attachment B.) Attachment C is a simplified geologic

map showing the approximate locations of the Federal and non-Federal parcels.

Non-Federal Lands

Parcel A: South Game Creek Bowl

Minturn 1:24,000, Leadville 1:100,000, Leadville 1:250,000 quadrangles. 

The South Game Creek parcel is located in Game Creek. The bedrock geology is Middle

Pennyslvanian Minturn Formation overlain by unconsolidated Holocene and Pleistocene

landslide deposits and thick colluvium (Tweto and others, 1978; Day and others, 1999). Minturn

Formation is composed of “grit, conglomerate, sandstone, shale, and intercalated beds of

carbonate rocks” (Tweto and Lovering, 1977).

There are no known mines, prospects or mining districts in these host rocks in the vicinity of the

parcel (Wilson, 2003). The closest mining district, Gilman-Redcliff, is 3 to 7 miles to the south. 

In the resource assessment of the White River National Forest, Toth and others (1993) did not

assign any potential for locatable mineral resources to the area surrounding this parcel. 

Therefore, mineral resource potential for locatable minerals in the Game Creek parcel is

considered to be low.

Parcel B: Vassar Meadows

Fulford 1:24,000, Vail 1:100,000, Leadville 1:250, 000 quadrangles.

Geologically, the Vassar Meadows parcel is mapped as Pleistocene (Bull Lake and younger)

unconsolidated glacial drift overlying Lower Triassic and Permian State Bridge Formation

(Attachment C) lying within the southeastern end of the downthrown, fault-bounded

Hardscrabble Mountain block (Tweto and others, 1978). The lower elevations of the parcel are

riparian wetlands in Quaternary alluvium. The sides of the valley are underlain by State Bridge

Formation, overlain by varying thicknesses of colluvium. Additional geologic mapping and

studies that could be consulted include Hubert (1954), Gableman (1949, 1950), Lueck (1970),

and Richards (1982). 

Parcel B lies 2 to 3 miles west of the Polar Star and Johnson mines and the Fulford and Brush

Creek mining areas (Gableman, 1949, 1950; Lueck, 1970; Richards, 1982; Brown, 1990;

Wilson, 2003). The area labeled “Fulford District” on Attachment C includes the Brush

Creek district in the north and the Fulford district in the south (Vanderwilt, 1947, p. 77-78). 

(According to Vanderwilt, Brush Creek district, active from 1912 to 1926, contained silver veins

in Dakota Sandstone. Mineralization in the Fulford district was said to be similar to Brush Creek,

although it is described as lead-silver in Paleozoic dolomite beds.) No mineral resource

potential was assigned to the Vassar Meadows area by Toth and others (1993). Therefore,

mineral resource potential for locatable minerals in Vassar Meadows is considered to be low.

85
C:\...\locmin\locmin83.wpd 2 December 1, 2004

Federal Lands

Parcel 1: Front Door

Empire 1:24,000, Denver West 1:100,000, Denver 1:250,000 quadrangles. 

Parcel 1, the Front Door, is an approximately 5 acre parcel located at the base of the Vail ski

area adjacent to high-density resort development. At the detailed scale of the provided parcel

map compared with the much smaller scale (1:48,000) geologic map, it is not possible to provide

a detailed geologic summary. When geologic mapping of this area was conducted (1940-41,

1946, 1961), the ski area did not exist. The area was mapped as Middle Pennsylvanian Minturn

Formation, which is composed of grit, conglomerate, sandstone, and shale, with intercalated

beds of carbonate rocks (Tweto and Lovering, 1977). Several carbonate beds in the Robinson

Limestone Member may be in or adjacent to the Front Door parcel. The Minturn Formation is

mostly gray, but it may be red in the upper part and in an irregular zone near the base. The

parcel appears to be on the east flank of the Vail syncline. 

There are no known mines, prospects, or locatable mineral occurrences in the vicinity. Toth and

others (1993) assessed this area as having no mineral resource potential. Therefore, mineral

resource potential for locatable minerals in Vassar Meadows is considered to be low.

LIST OF ATTACHMENTS:

A. Report request (provided by U.S. Forest Service).

B. Exhibits A and B. Location description exclusive of land reservations, outstanding

rights, and other exclusions (provided by U.S. Forest Service).

C. Simplified geologic map showing locations of the parcels (modified from Tweto and

Lovering, 1977; Tweto and others, 1978; Day and others, 1999; Wilson, 2003).

REFERENCES:

Brown, S.D., 1990, Mineral appraisal of the White River National Forest, Colorado: U.S.

Bureau of Mines MLA 9-90, 380 p.

Day, W.C., Green, G.N., Knepper, D.H., Jr., and Phillips, R.C., 1999, Spatial geologic data

model for the Gunnison, Grand Mesa, Uncompahgre National Forests mineral resource

assessment area, southwestern Colorado and digital data for the Leadville, Montrose,

Durango, and the Colorado parts of the Grand Junction, Moab, and Cortez 1o

 X 2o

geologic maps: U.S. Geological Survey Open-File Report 99-427. 

http://pubs.usgs.gov/of/1999/ofr-99-0427/arc_quad/leadvlle/

Gabelman, J.W., 1949, Geology and ore deposits of the Fulford mining district, Eagle County,

Colorado with reconnaissance of the Brush Creek mining district: Golden, Colo.,

Colorado School of Mines Ph.D. dissertation, 188 p.

86
C:\...\locmin\locmin83.wpd 3 December 1, 2004

Gabelman, J.W., 1950, Geology of the Fulford and Brush Creek mining districts, Eagle County,

Colorado: Colorado Mining Association, Minerals Yearbook, p. 50-52.

Hubert, J.F., 1954, Structure and stratigraphy of an area east of Brush Creek, Eagle County,

Colorado: Boulder, University of Colorado M.S. thesis, 104 p. 

Lueck, E.W., 1970, The geology of the Fulford mining district (Cenozoic), Eagle County,

Colorado: Iowa City, University of Iowa M.S. thesis, 78 p.

Richards, B.D., 1982, Geology of the Mississippian Leadville Limestone; Fulford area, Eagle

County, Colorado: Geological Society of America Abstracts with Programs, v. 14, no. 3,

135 p.

Toth, M.I., Wilson, A.B., Cookro, T.M., Bankey, Viki, Lee, G.K., and Case, J.E., 1993, Mineral

resource potential and geology of the White River National Forest and the Dillon Ranger

District of the Arapaho National Forest, Colorado, with a section on Salable

commodities, by J.S. Dersch: U.S. Geological Survey Bulletin 2035, 117 p.

Tweto, Ogden, and Lovering, T.S., 1977, Geology of the Minturn 15-minute quadrangle, Eagle

and Summit Counties, Colorado: U.S. Geological Survey Professional Paper 956, 96 p.,

1 pl., scale 1:48,000.

Tweto, Ogden, Moench, R.H., and Reed, J.C., Jr., 1978, Geologic map of the Leadville 1o

 X 2o

quadrangle, northwestern Colorado: U.S. Geological Survey Miscellaneous

Investigations Series Map I-999, scale 1:250,000.

Vanderwilt, J.W., 1947, Mineral Resources of Colorado: State of Colorado Mineral Resources

Board, p. 77-78.

Wilson, A.B., 2003, Databases and simplified geology for mineralized areas, claims, mines and

prospects in Colorado: U.S. Geological Survey Open-File Report 03-090.

87
C:\...\locmin\locmin83.wpd 4 December 1, 2004

Attachment A. Report request (provided by U.S. Forest Service)

88
C:\...\locmin\locmin83.wpd 5 December 1, 2004

Attachment B. Exhibits A and B. Location description exclusive of

land reservations, outstanding rights, and other exclusions (provided by

U.S. Forest Service).

89
C:\...\locmin\locmin83.wpd 6 December 1, 2004

Attachment C. Simplified geologic map showing location of the parcels (modified from Tweto and Lovering, 1977; T

Day and others, 1999; Wilson, 2003). Qa, Holocene and Pleistocene alluvium; Ql, Holocene and Pleistocene landQd, Pleistocene glacial drift; TKi, Larmide intrusive rocks; TRPs, Lower Triassic and Permian State Bridge FormPennsylvanian Minturn Formation. Circles and squares are locations of mines or prospects from the MAS and MR

2003), respectively. Due to overprinting of multiple entries in the same locations, the color of these points is mean

detailed information, see the original maps.) Approximate scale, 1 mile

90
SOUTH DAKOTA

91
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LOCATABLE MINERAL REPORT FOR THE

CATTAIL LAND EXCHANGE OFFER,

BLACK HILLS NATIONAL FOREST,

CUSTER AND FALL RIVER COUNTIES, SOUTH DAKOTA

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

March 8, 2005

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author.

92
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U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

(303) 236-5593

FAX (303) 236-3200

awilson@usgs.gov

April 1, 2005

Mr. Randall Karstaedt

Director, Physical Resources

U.S.D.A. Forest Service

P.O. Box 25127

Lakewood, CO 80225-0127

Dear Mr. Karstaedt:

This report is in response to your February 9 request (received February 15) for information on

locatable mineral resources in the Cattail land exchange proposal in which The Nature

Conservancy and Oonagh Wood and Leonard Wood have offered certain non-Federal lands

within the Black Hills National Forest in exchange for Federal lands also within the Black Hills

National Forest. 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in Exhibits

A and B, which were included with your request. These lands comprise approximately 1,342.04

acres in Custer and Fall River Counties, South Dakota.

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: C.J. Nutt

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin87.wpd 1 March 8, 2005

For the legal location description of lands considered for exchange, refer to Exhibits A and B in

Attachments A and B. The report request is Attachment C. Simplified geologic maps for the

properties are in Attachments D, E, and F.

Non-Federal Lands

TNC property–Lithograph North and Lithograph South

Jewel Cave 1:24,000, Tinton 1:62,500, Sundance 1:100,000, Gillette 1:250,000 quadrangles. 

The area is mapped as Lower Permian and Pennsylvanian Minnelusa Formation (PIPm,

Attachment D) (Darton and Page, 1925; DeWitt and others, 1989; Martin and others, 2004). It

is a light-brown to red and gray sandstone, solution breccia (anhydrite in subsurface), limestone,

and shale. The TNC property appears to be located near the lower part of the formation, where

there may be weak uranium anomalies. 

The TNC property is in an area without potential for locatable commodities (DeWitt and others,

1986) and is not within known metallic mineral areas (Wilson and DeWitt, 1995). Therefore,

locatable mineral resource potential on this parcel is very low. The property is in an area

assigned low potential (with a low degree of certainty) for small- to medium-sized stratabound

oil and gas deposits (DeWitt and others, 1986).

Wood property–Bogli Ranch

Minnekahta NE 1:24,000, Hot Springs 1:100,000, Hot Springs 1:250,000 quadrangles. 

Bogli Ranch property is mapped as Lower Permian and Pennsylvanian Minnelusa Formation

(PIPm, Attachment E; Martin and others, 2004). The Permian (upper) part of the unit is mostly

“brecciated red and yellow sandstone and yellow to gray thin-bedded limestone.” The base of

the unit is “a prominent mudstone called the ‘red marker’.” The Pennsylvanian section is

“slightly brecciated yellowish-gray dolomite and yellow calcareous sandstone,” locally

containing thin carbonaceous shale (Wolcott and others, 1962).

Bogli Ranch is in an area without potential for locatable commodities (DeWitt and others, 1986)

and is south of known metallic mineral areas (Wilson and DeWitt, 1995). Therefore, locatable

mineral resource potential on this parcel is very low. The property is in an area assigned low

potential (with a low degree of certainty) for small- to medium-sized stratabound oil and gas

deposits (DeWitt and others, 1986).

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Federal Lands

Buck Canyon property

Cascade Springs 1:24,000, Fall River 1:100,000, Hot Springs 1:250,000 quadrangles. 

Buck Canyon parcel is on the northeast side of Falls Canyon in the Jurassic to Lower Cretaceous

Inyan Kara Group rocks (Post, 1967; Martin and others, 2004). The oldest rocks exposed in the

canyon are the uppermost member of the Upper Jurassic Sundance Formation, the Redwater

Shale Member. This is overlain stratigraphically and topographically by Unkpapa Sandstone.

These units are shown on the detailed 1:24,000-scale map (Post, 1967) but not on the simplified

State-scale geologic map (Martin and others, 2004; Attachment F). Overlying the Unkpapa is a

thin band of mudstone overlain by cliff-forming, fine grained channel sandstone of the Lower

Cretaceous Chilson Member of the Lakota Formation (Post, 1967). Variegated mudstone and

minor sandstone of the Fuson Member of the Lakota Formation may overlie the Chilson (Post,

1967) at the extreme eastern margin of the property. Lakota Formation (and its members), is the

lower part of the Inyan Kara Group, unit Kfl on Attachment F.

Buck Canyon parcel is in an area with high potential for medium-sized roll-front deposits

containing uranium and vanadium (DeWitt and others, 1986). The property is in an area

assigned low potential for small bedded sedimentary coal deposits (DeWitt and others, 1986). 

At the scale of the assessment, it is possible that the parcel is at the margin of an area assessed

with moderate potential for medium-sized stratabound oil and gas deposits (DeWitt and others,

1986).

Green Canyon property

Angostura Reservoir 1:24,000, Fall River 1:100,000, Hot Springs 1:250,000 quadrangles. 

Green Canyon parcel is on the east flank of the Cascade anticline, in Lower Cretaceous middle

and upper parts of the Fall River Formation. Fall River Formation, the upper part of the Inyan

Kara Group (unit Kfl, Attachment F), consists of interbedded sandstone and mudstone. The

parcel may be overlain by poorly sorted sand and gravel Quaternary terrace deposits (unit Qt,

Attachment F) (Connor, 1963).

Green Canyon parcel is in an area with moderate potential for small- to medium-sized roll-front

deposits containing uranium and vanadium (DeWitt and others, 1986). However, there are no

known deposits on the east flank of the Cascade anticline. The property is in an area assigned

low potential (with a low degree of certainty) for small- to medium-sized stratabound oil and gas

deposits (DeWitt and others, 1986).

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Cattail property

Cascade Springs 1:24,000, Fall River 1:100,000, Hot Springs 1:250,000 quadrangles. 

The Cattail parcel is between Falls and Lindsley Canyons in Lower Cretaceous Lakota and Fall

River Formations of the Inyan Kara Group rocks (Post, 1967; Martin and others, 2004, unit Kfl). 

The oldest rocks exposed are cliff-forming channel sandstones of the Chilson Member of the

Lakota Formation overlain by variegated mudstone and minor sandstone of the Fuson Member. 

The lowest unit of the Fall River Formation is a siltstone. In the parcel, it is overlain by a cliffforming sandstone in the middle unit of the Fall River Formation topped by red to variegated

mudstone and sandstone of the upper unit (Post, 1967). 

Buck Canyon parcel is in an area with high potential for medium-sized roll-front deposits

containing uranium and vanadium (DeWitt and others, 1986). The property is in an area

assigned low potential for small bedded sedimentary coal deposits and moderate potential for

medium-sized stratabound oil and gas deposits (DeWitt and others, 1986).

Ruby Creek property

Berne 1:24,000, Mount Rushmore 1:100,000, Hot Springs 1:250,000 quadrangles. 

Proterozoic quartz-biotite-garnet schist (unit Xbs, Attachment D) underlies most of the Ruby

Creek property which is near the axis of the Park Dome (Redden, 1968). There may be small,

layered pegmatite bodies on the property.

Ruby Creek property is less than 0.5 km west of the Ballard, Crown, and Rachel D. mines

(DeWitt and others, 1988). The first two mines are pegmatites with large amounts of mica, the

last is a deposit rich in feldspar. These deposits formed about 1.6 to 1.8 Ga (billion years ago). 

Immediately west of the property is the Custer Park No. 2 Placer. The area is in the Park

mineralized area which contains deposits of potassium feldspar and mica (Wilson and DeWitt,

1995). The parcel is in an area assigned high potential for small- to medium-sized deposits of

pegmatite commodities (such as feldspar, mica, lithium, beryllium, tantalum, and tungsten) with

the exception of tin (DeWitt and others, 1986). 

96
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Argyle property

Pringle 1:24,000, Mount Rushmore 1:100,000, and Hot Springs 1:250,000 quadrangles. 

Lower Permian and Pennsylvanian Minnelusa Formation (unit PIPm, Attachment E) underlies

the Argyle property (Darton and Paige, 1925; DeWitt and others, 1989). It is a light-brown to

red and gray sandstone, solution breccia (anhydrite in subsurface), limestone, and shale. 

The Argyle property is in an area without potential for locatable commodities (DeWitt and

others, 1986) and is outside the areas identified as metallic mineral areas (Wilson and DeWitt,

1995). Therefore, locatable mineral resource potential on this parcel is very low. The property

is in an area assigned low potential (with a low degree of certainty) for small- to medium-sized

stratabound oil and gas deposits (DeWitt and others, 1986).

LIST OF ATTACHMENTS:

A. Exhibit A. Legal description of non-Federal land considered in this exchange (provided

by U.S. Forest Service).

B. Exhibit B. Legal description of Federal land considered in this exchange (provided by

U.S. Forest Service).

C. Report request (provided by U.S.D.A. Forest Service).

D. Simplified geologic map (after Martin and others, 2004) showing approximate location

of TNC (Lithograph) and Ruby Creek Properties in the Jewel Cave and Berne

quadrangles. 

E. Simplified geologic map (after Martin and others, 2004) showing approximate location

of Wood (Bogli Ranch) and Argyle Properties in the Minnekahta NE and Pringle

quadrangles.

F. Simplified geologic map (after Martin and others, 2004) showing approximate location

of Black Canyon, Cattail, and Green Canyon Properties in the Cascade Springs and

Angostura Reservoir quadrangles.

97
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REFERENCES:

Connor, J.J., 1963, Geology of the Angostura Reservoir quadrangle, Fall River County, South

Dakota: U.S. Geological Survey Bulletin 1063-D, p. 85-126, scale 1:24,000.

Darton, N.H., and Paige, Sidney, 1925, Central Black Hills [quadrangle], South Dakota: U.S.

Geological Survey Geologic Atlas of the United States, Folio 219, scale 1:125,000.

DeWitt, Ed, Redden, J.A., Buscher, David, and Wilson, A.B., 1989, Geologic map of the Black

Hills area, South Dakota and Wyoming: U.S. Geological Survey Miscellaneous

Investigations Series Map I-1910, scale 1:250,000.

DeWitt, Ed, Redden, J.A., Wilson, A.B., and Buscher, David, 1986, Mineral resource potential

and geology of the Black Hills National Forest, South Dakota and Wyoming, with a

section on Salable commodities, by John S. Dersch: U.S. Geological Survey Bulletin

1580, 135 p., 4 plates.

DeWitt, Ed, Buscher, David, Wilson, A.B., and Johnson, Tom, 1988, Map showing locations of

mines, prospects, and patented mining claims, and classification of mineral deposits in

the Berne 7 1/2-minute quadrangle, Black Hills, South Dakota: U.S. Geological Survey

Miscellaneous Field Studies Map MF-1978-L, scale 1:24,000.

Martin, J.E., Sawyer, J.F., Fahrenbach, M.D., Tomhave, D.W., and Schulz, L.D., 2004,

Geologic map of South Dakota: South Dakota Geological Survey General Map 10, scale

1:500,000.

[www.jurassic2.sdgs.usd.edu/pubs/pdf/SDGeomap_20040630.pdf/]

Post, E.V., 1967, Geology of the Cascade Springs quadrangle, Fall River County, South Dakota: 

U.S. Geological Survey Bulletin 1063-L, p. 443-504, scale 1:24,000.

Redden, J.A., 1968, Geology of the Berne quadrangle, Black Hills, South Dakota: U.S.

Geological Survey Professional Paper 297-F, scale 1:24,000.

Wilson, A.B., and DeWitt, Ed, 1995, Maps showing metallic mineral districts and mines in the

Black Hills, South Dakota and Wyoming: U.S. Geological Survey Miscellaneous

Investigations Series Map I-2445, scale 1:100,000.

Wolcott, D.E., Bowles, C.G., Brobst, D.A., and Post, E.V., 1962, Geologic and structure map of

the Minnekahta NE quadrangle, Fall River and Custer Counties, South Dakota: U.S.

Geological Survey Mineral Investigations Field Studies Map MF-242, scale 1:24,000.

98
C:\...\locmin\locmin87.wpd 6 March 8, 2005

Attachment A. Legal description of non-Federal land considered in this exchange

(provided by U.S. Forest Service), excluding Outstanding Rights and

Reservations. 

99
C:\...\locmin\locmin87.wpd 7 March 8, 2005

Attachment B. Legal description of Federal land considered in this exchange

(provided by U.S. Forest Service), excluding Outstanding Rights and

Reservations. 

100
C:\...\locmin\locmin87.wpd 8 March 8, 2005

Attachment C. Report request (provided by U.S. Forest Service).

101
C:\...\locmin\locmin87.wpd 9 March 8, 2005

Attachment D. Simplified geologic map (after Martin and others, 2004) showing the

approximate location of the TNC (Lithograph) and Ruby Creek properties in the Jewel

Cave and Berne quadrangles. The TNC (Lithograph) property is entirely within

Pennsylvanian to early Permian Minnelusa Formation (PIPm). The Ruby Creek

property is in Proterozoic metamorphosed black shale (Xbs) and metamorphosed

tuffaceous shale (Xms).

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Attachment E. Simplified geologic map (after Martin and others, 2004) showing the

approximate location of the Wood (Bogli Ranch) and Argyle properties in the

Minnekahta NE and Pringle quadrangles. Both properties are entirely within

Pennsylvanian to early Permian Minnelusa Formation (PIPm). 

103
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Attachment F. Simplified geologic map (after Martin and others, 2004) showing

approximate location of Black Canyon, Cattail, and Green Canyon properties. On this

simplified geologic map, all three properties are shown entirely within the Fall River

and Lakota Formations (Kfl) of the Lower Cretaceous Inyan Kara Group.

104
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LOCATABLE MINERAL REPORT FOR THE

COLE DRAW (EDOFF) EXCHANGE OFFER,

BUFFALO GAP NATIONAL GRASSLAND,

NEBRASKA NATIONAL FOREST,

PENNINGTON AND CUSTER COUNTIES, SOUTH DAKOTA

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

March 24, 2003

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author.

105
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U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

(303) 236-5593

FAX (303) 236-3200

awilson@usgs.gov

March 24, 2003

Mr. M. M. Underwood

Director, Physical Resources

U.S. Forest Service

PO Box 25127

Lakewood, CO 80225-0127

Dear Mr. Underwood:

This report is in response to your January 6 request for information on locatable mineral

resources in a land exchange proposal in which Lorence, Scott, and Veronica Edoff have offered

certain non-Federal lands within Buffalo Gap National Grassland in exchange for Federal lands

also within Buffalo Gap National Grassland, Nebraska National Forest. 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in Exhibits

A and B, which were included with your request. These lands comprise 1,634.32 acres in

Pennington and Custer counties, South Dakota.

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: W.C. Day

E.A. du Bray

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin75.wpd 1 March 24, 2003

For the legal location description of lands considered for exchange, refer to Exhibits A and B in

Attachments A and B. Original report request is in Attachment C.

Non-Federal Lands

Scenic SW, Creston 1:24,000, Wall 1:100,000, Hot Springs 1:250,000 quadrangles. 

The southern parcel is mapped by King and Raymond (1971) as Cretaceous Pierre Shale

(Attachment D), described as “black shale containing layers with large calcareous concretions

and marine fossils.

The northern parcel is not mapped at detailed scale. Extrapolating from the King and Raymond

map and comparing it to the State-scale geologic map suggests that the parcel may also be Pierre

Shale. Without more detailed maps or a site visit, this is purely hypothetical.

 

Federal Lands

Scenic SW, Folsom, and Creston 1:24,000, Wall 1:100,000, Hot Springs 1:250,000 quadrangles.

All of the Federal parcels are mapped (King and Raymond, 1971) as Cretaceous Pierre Shale

(see description above). It is expected that the parcels along the Cheyenne River are overlain by

Quaternary deposits, but the geologic map does not show these units. 

Mineral Assessment for all Lands in the Exchange

There are no known locatable mineral deposits near the parcels involved in the exchange

(McFaul and others, 2000; Causey, 1998, Frank, 1999). The potential for locatable mineral

resources is low. 

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REFERENCES:

Causey, J. D., 1998, MAS/MILS mineral location database information: U.S. Geological

Survey, Spatial Data Delivery Website. 

[No longer available online in this format]

Frank, D.G. , 1999, Mineral Resource Data System (MRDS) data in Arc View Shape File

Format, for Spatial Data Delivery Project, 1999: Not a formal series. Data provided for

Spatial Data Delivery Project sddmrds version 1.1 Mineral Resource Data System data

for Spatial Data Delivery Project, February, 1999, U.S. Geological Survey, Spokane,

Washington. [No longer available online in this format]

King, R.U., and Raymond, W.H., 1971, Geologic map of the Scenic area, Pennington, Shannon,

and Custer Counties, South Dakota: U.S. Geological Survey Miscellaneous Geologic

Investigations Map I-662, scale 1:31,680.

McFaul, E.J., Mason, G.T., Jr., Ferguson, W.B., and Lipin, B.R., 2000, U.S. Geological Survey

Mineral Databases–MRDS and MAS/MILS: U.S. Geological Survey Digital Data Series

DDS-52. [Use of this data CD is not recommended.]

LIST OF ATTACHMENTS:

A. Exhibit A, Non-Federal land (provided by U.S. Forest Service).

B. Exhibit B, Federal land (provided by U.S. Forest Service).

C. Report request (provided by U.S. Forest Service)

D. Geologic map showing location of parcels exclusive of non-Federal lands in T. 2 S., R.

12 E. 

108
C:\...\locmin\locmin75.wpd 3 March 24, 2003

Attachment A. Exhibit A (provided by U.S. Forest Service)

109
C:\...\locmin\locmin75.wpd 4 March 24, 2003

Attachment B. Exhibit B (provided by U.S. Forest Service)

110
C:\...\locmin\locmin75.wpd 5 March 24, 2003

Attachment C. Report request (provided by U.S. Forest Service)

111
C:\...\locmin\locmin75.wpd 6 March 24, 2003

Attachment D. Geology of the Scenic area (after King and Raymond,

1971). Green area is Cretaceous Pierre Shale, yellow is Oligocene Chadron

Formation. Thin band of grass green barely visible between the two units is upper part

of Pierre shale where highly colored shale formed from Eocene weathering to a

maximum depth of 300 feet.

112
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LOCATABLE MINERAL REPORT FOR THE

CORTNEY CREEK (SIDES RANCH) EXCHANGE OFFER,

BUFFALO GAP NATIONAL GRASSLAND,

NEBRASKA NATIONAL FOREST,

FALL RIVER COUNTY, SOUTH DAKOTA

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

September 30, 2004

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author.

113
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U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

(303) 236-5593

FAX (303) 236-3200

awilson@usgs.gov

September 30, 2004

Mr. Randall Karstaedt

Director, Physical Resources

U.S. Forest Service

PO Box 25127

Lakewood, CO 80225-0127

Dear Mr. Karstaedt:

This report is in response to your August 11 request for information on locatable mineral

resources in a land exchange proposal in which Sides Ranch, Inc. has offered certain non-Federal

lands within Buffalo Gap National Grassland in exchange for Federal lands also within Buffalo

Gap National Grassland (administered by Nebraska National Forest). 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in Exhibit

B, which was included with your request. These lands comprise 658.78 acres in Fall River

County, South Dakota. No report was requested for land in Exhibit A. 

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: C.J. Nutt

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin80.wpd 1 September 30, 2004

A location map is in Attachment A. For the legal location description of lands considered for

exchange, refer to Exhibit B in Attachment B. The original report request is in Attachment C.

Federal Lands

Hay Butte Canyon 1:24,000, Hot Springs 1:100,000, Hot Springs 1:250,000 quadrangles. 

The parcel is not mapped at detailed scale. At 1:500,000, entire parcel is mapped by Martin and

others (2004) as Upper Cretaceous Pierre Shale. This shale unit is blue-gray to dark-gray, fissile

to blocky shale with persistent beds of bentonite, black organic shale, and light-brown chalky

shale. It may contain minor sandstone, conglomerate, and abundant carbonate and ferruginous

concretions (Martin and others, 2004). Although this area is shown on several small scale or

state-wide geologic map compilations (Martin and others, 2004; Ellis and Colton, 1994, DeWitt

and others, 1989), it does not appear that any new geologic field mapping has been published in

this area since 1902 (Darton, 1902). No larger scale maps of this area could be located.

There are no known locatable mineral deposits near the parcels involved in the exchange (U.S.

Geological Survey, 2004). The potential for locatable mineral resources is considered to be low. 

REFERENCES:

Darton, N.H., 1902, Oelrichs [quadrangle], South Dakota: U.S. Geological Survey Geological

Atlas of the United States, Folio 85, scale 1:250,000.

DeWitt, Ed, Redden, J.A., Buscher, D.P., and Wilson, A.B., 1989, Geologic map of the Black

Hills area, South Dakota and Wyoming: U.S. Geological Survey Miscellaneous

Investigations Series Map I-1910, scale 1:250,000.

Ellis, M.S., and Colton, R.B., 1994, Geologic map of the Powder River basin and surrounding

area, Wyoming, Montana, South Dakota, North Dakota, and Nebraska: U.S. Geological

Suvey Miscellaneous Investigations Series Map I-2298, scale 1:500,000.

Martin, J.E., Sawyer, J.F., Fahrenbach, M.D., Tomhave, D.W., and Schulz, L.D., 2004,

Geologic map of South Dakota: South Dakota Geological Survey General Map 10, scale

1:500,000.

U.S. Geological Survey, 2004, Mineral resources on-line spatial data, http://mrdata.usgs.gov/

LIST OF ATTACHMENTS:

A. Generalized location map (provided by U.S. Forest Service).

B. Exhibit B, Federal land (provided by U.S. Forest Service).

C. Report request (provided by U.S. Forest Service)

115
C:\...\locmin\locmin80.wpd 2 September 30, 2004

Attachment A. Generalized location map (provided by U.S. Forest

Service)

116
C:\...\locmin\locmin80.wpd 3 September 30, 2004

Attachment B. Exhibit B (provided by U.S. Forest Service)

117
C:\...\locmin\locmin80.wpd 4 September 30, 2004

118
C:\...\locmin\locmin80.wpd 5 September 30, 2004

Attachment C. Report request (provided by U.S. Forest Service)

119
C:\...\locmin\locmin84.wpd January 6, 2005

LOCATABLE MINERAL REPORT FOR THE

INDIAN CREEK LAND EXCHANGE OFFER,

BUFFALO GAP NATIONAL GRASSLAND,

NEBRASKA NATIONAL FOREST,

PENNINGTON AND CUSTER COUNTIES, SOUTH DAKOTA

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

January 6, 2005

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author.

120
C:\...\locmin\locmin84.wpd January 6, 2005

U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

(303) 236-5593

FAX (303) 236-3200

awilson@usgs.gov

January 6, 2005

Mr. Randall Karstaedt

Director, Physical Resources

U.S. Forest Service

PO Box 25127

Lakewood, CO 80225-0127

Dear Mr. Karstaedt:

This report is in response to your December 29 request (received January 5) for information on

locatable mineral resources in a land exchange proposal in which the Dakota Partnership has

offered certain non-Federal lands within Buffalo Gap National Grassland in exchange for

Federal lands also within Buffalo Gap National Grassland (administered by Nebraska National

Forest). 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in Exhibits 

A and B, which were included with your request. These lands comprise 5,998 acres in

Pennington and Custer Counties, South Dakota. 

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: C.J. Nutt

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin84.wpd 1 January 6, 2005

The original report request is in Attachment A. For the legal location description (exclusive of

reservations and outstanding rights) of lands considered for exchange, refer to Attachments B

and C. A simplified geologic map showing approximate parcel locations is in Attachment D. 

Non-Federal Lands

Huetmacher Table, Scenic SW, and Sheep Mountain Table 1:24,000; Wall 1:100,000;

Hot Springs 1:250,000 quadrangles.

The bedrock geology of all the non-Federal parcels was mapped at a scale of 1:31,680 (1⁄2 mile

per inch) by King and Raymond (1971) and all of the rock unit descriptions that follow are from

this map. In this region, Upper Cretaceous Pierre Shale, a black shale containing calcareous

concretions and marine fossils, is locally capped with as much as 300 ft of the “Interior Beds.”

Named for the town of Interior, this unit is composed of highly colored shales formed during the 

Eocene(?) from weathered the Pierre Shale. Oligocene Chadron Formation overlies the Pierre

Shale (and Interior Beds). Chadron Formation is composed of gray to pink sandstone and clay,

with locally prominent basal conglomerate and channel sandstone. It contains fossils of

titanothere (an ancient rhino-like mammal). Oligocene Brule Formation tops the section. It

contains pinkish-gray to greenish-gray clay, silt, sand, and volcanic ash containing channel

sandstones, clastic dikes, and chalcedony veinlets. Oreodon (an ancient camel-like mammal)

and turtle fossils are common in the Brule Formation.

Parcels:

P-1, on Zebell Table, contains all four of the above units (King and Raymond, 1971). However,

at State-scale, this area is mapped as Quaternary eolian deposits that were deposited as

sand sheets, dunes, and as a veneer on uplands (see Attachment D, after Martin and

others, 2004). 

P-2 is mostly Pierre Shale, with the three overlying units exposed near the south end (King and

Raymond, 1971). The State-scale map (Martin and others, 2004) shows the northwestern

end of the parcel in Quaternary alluvium and the southernmost end in Quaternary eolian

deposits. 

P-3 contains all four of the above units (King and Raymond, 1971). At State-scale (Martin and

others, 2004), the parcel is shown almost entirely covered with Quaternary eolian

deposits overlying undifferentiated White River Group, which contains Brule and Chadron

Formations. 

P-4 is mostly Pierre Shale overlain by Chadron Formation. No Interior Beds are mapped at the

contact (King and Raymond, 1971). The State-scale map shows the lower elevations as

Quaternary alluvium and the higher elevations in Pierre Shale and undifferentiated White

River Group (Martin and others, 2004). There is a vague hint that a molybdenum and

uranium prospect may exist in the vicinity (mrdata.usgs.gov), but the data are incomplete

and unreliable.

P-5 is almost entirely in Chadron Formation (King and Raymond, 1971), part of the

undifferentiated White River Group (Martin and others, 2004). A single uranium

prospect, Hart Table prospect, may be located within a few miles to the east

(mrdata.usgs.gov). 

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No locatable minerals have been discovered or produced in the vicinity of these parcels. The

mineral resource potential for locatable minerals on these five parcels is low.

Federal Lands NF-4

Folsom and Red Shirt NE 1:24,000; Wall 1:100,000, Hot Springs 1:250,000 quadrangles. 

Parcel NF-4 is entirely within an area mapped as Pierre Shale (King and Raymond, 1971). The

State geologic map (Martin and others, 2004) indicates the lower elevations are covered with

Quaternary alluvium and the upper elevations with Quaternary terrace deposits.

There are no mines, prospects, or occurrences of any locatable minerals in the vicinity. Mineral

resource potential for locatable minerals on this parcel is low.

Federal Lands NF-1, NF-2, NF-3

Fairburn NE 1:24,000; Mount Rushmore 1:100,000, Hot Springs 1:250,000 quadrangles. 

As far as known, there is no detailed mapping of the area covering these three parcels. The

entire area was mapped at 1:125,000 (Darton and Paige, 1925) as undifferentiated Brule and

Chadron Formations. No larger scale maps of this area could be located. At State-scale (Martin

and others, 2004, 1:500,000), parcels NF-1 and NF-3 are entirely within the White River Group,

which includes the Brule and Chadron Formations. Pierre Shale is exposed in the southwestern

part of Parcel NF-2 (Martin and others, 2004). 

There are no known locatable mineral deposits near the parcels involved in the exchange (U.S.

Geological Survey, 2004). (The feldspar deposit shown in the MAS dataset on the USGS

mrdata.usgs.gov site on Red Shirt NE quad is erroneously located–it belongs in Cicero Peak

quadrangle, four quadrangles to the west). The potential for locatable mineral resources is

considered to be low. 

123
C:\...\locmin\locmin84.wpd 3 January 6, 2005

REFERENCES:

Darton, N.H., and Paige, Sidney, 1925, Central Black Hills, South Dakota: U.S. Geological

Survey Geological Atlas of the United States, Folio 219, scale 1:125,000.

DeWitt, Ed, Redden, J.A., Buscher, D.P., and Wilson, A.B., 1989, Geologic map of the Black

Hills area, South Dakota and Wyoming: U.S. Geological Survey Miscellaneous

Investigations Series Map I-1910, scale 1:250,000.

King, R.U., and Raymond, W.H., 1971, Geologic map of the Scenic area, Pennington, Shannon,

and Custer Counties, South Dakota: U.S. Geological Survey Miscellaneous Geologic

Investigations Map I-662, scale 1:31,680.

Martin, J.E., Sawyer, J.F., Fahrenbach, M.D., Tomhave, D.W., and Schulz, L.D., 2004,

Geologic map of South Dakota: South Dakota Geological Survey General Map 10, scale

1:500,000. [http://jurassic2.sdgs.usd.edu/pubs/pdf/SDGeomap_20040630.pdf]

U.S. Geological Survey, 2004, Mineral resources on-line spatial data, http://mrdata.usgs.gov/

LIST OF ATTACHMENTS:

A. Report request (provided by U.S. Forest Service).

B. Exhibit A, location of non-Federal land (provided by U.S. Forest Service).

C. Exhibit B, location of Federal land (provided by U.S. Forest Service).

D. Simplified geologic map (after Martin and others, 2004).

124
C:\...\locmin\locmin84.wpd 4 January 6, 2005

Attachment A. Report request (provided by U.S. Forest Service)

125
C:\...\locmin\locmin84.wpd 5 January 6, 2005

Attachment B. Exhibit A (provided by U.S. Forest Service)

126
C:\...\locmin\locmin84.wpd 6 January 6, 2005

Attachment C. Exhibit B (provided by U.S. Forest Service)

127
C:\...\locmin\locmin84.wpd 7 January 6, 2005

Attachment D. Simplified geologic map (after Martin and others, 2004) and approxof parcels considered for exchange (areas outlined in red are non-Federal parcels, arare Federal parcels). Qal, Quaternary alluvium; Qt, Quaternary terrace deposits; Qeeolian; Tw, Tertiary (Oligocene and Eocene) White River Group (includes Brule and Formations); Kp, Upper Cretaceous Pierre Shale (includes Interior Beds). 

128
C:\...\locmin\locmin78.wpd April 15, 2004

LOCATABLE MINERAL REPORT FOR THE

MISSOURI BREAKS LAND EXCHANGE OFFER,

FORT PIERRE NATIONAL GRASSLAND,

NEBRASKA NATIONAL FOREST,

STANLEY COUNTY, SOUTH DAKOTA

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

April 15, 2004

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author.

129
C:\...\locmin\locmin78.wpd April 15, 2004

U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

(303) 236-5593

FAX (303) 236-3200

awilson@usgs.gov

April 15, 2004

Ms. Michele O’Connell

Acting Director, Physical Resources

U.S.D.A. Forest Service

PO Box 25127

Lakewood, CO 80225-0127

Dear Ms. O’Connell:

This report is in response to your January 23 request for information on locatable mineral

resources in the Missouri Breaks land exchange proposal in which the Randy and Linda Stroup

have offered certain non-Federal lands within the Fort Pierre National Grassland in exchange for

Federal lands also within the Fort Pierre National Grassland. 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in Exhibits

A and B, which were included with your request. These lands comprise approximately 512.59

acres in Stanley County, South Dakota.

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: W.C. Day

E.A. du Bray

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin78.wpd 1 April 15, 2004

Non-Federal and Federal Lands

Rousseau 1:24,000, Canning 1:62,500, Pierre 1:100,000, Pierre 1:250,000 quadrangles. 

All three parcels considered for this exchange are within about 2 square miles and have similar

geologic settings. Each parcel contains the Virgin Creek Member of the Upper Cretaceous

Pierre Shale (Crandell, 1954). The northern and southern parcels may include exposures of the

underlying Verendrye Member, and the northernmost parcel also may include a small knob of

the overlying Mobridge Member. From youngest to oldest, these units are described by Crandell

(1954):

The Mobridge member consists of partly indurated calcareous shale. The proportion of calcium

carbonate ranges from 15 to 27 percent. The member is gray where unoxidized and grayish orange where

weathered. The shale tends to part along laminae, which range in thickness from one-sixtieth to onetenth of an inch. The color differences probably are related to variations in grain size, coarser grained

laminae oxidizing more rapidly than the finer ones. Outcrops are restricted to seven small knobs in the

southern part of the quadrangle from which the top of the member has been removed by erosion. The

maximum thickness that remains is about 25 feet.

The Virgin Creek member consists of olive-gray to light olive-gray shale, claystone, mudstone, and

intercalated beds of bentonite. The lower part of the member is predominantly shale that weathers into

thin flakes and chips less than an inch in diameter. This lower part of the member contains 15 or more

bentonite beds ranging in thickness from a fraction of an inch to 6 inches. The upper part of the member

consists predominantly of claystone and mudstone that weather to gumbo. A zone of undetermined

thickness at the top of the member is locally calcareous, although it has the same appearance as the

underlying noncalcareous beds. Bentonite beds less than an inch thick are intercalated sporadically

throughout the upper part of the member. The Virgin Creek member is very susceptible to slumping. 

The member is 120 feet thick in the southeast part of the Canning quadrangle [and may thicken to the

west]. The top of the member is marked by a change in lithology from gray claystone to the grayishorange calcareous shale of the overlying Mobridge member. 

The Verendrye member consists of 140 to 150 feet of light olive-gray to olive-gray mudstone and

claystone and subordinate amount of shale. The member weathers to light olive-gray or brownish-gray

gumbo. Because of the almost invariable gumbo cover, which is several inches to several feet thick,

stratification is not readily visible on outcrops. The member contains concretions of iron-manganese

carbonate that range from a few inches to several feet in diameter. These concretions are light olive-gray

where fresh, dark purple where weathered. The Verendrye member forms smooth slopes wherever

exposed and is subject to extensive slumping. The top of the member is marked by a transition from

gumbo forming mudstone to shale and claystone of the Virgin Creek member that break down to small

flakes and chips. This contact coincides with the base of a zone containing numerous bentonite beds in

the lower part of the overlying Virgin Creek member.

131
C:\...\locmin\locmin78.wpd 2 April 15, 2004

A prospect is located immediately to the northeast of the northernmost (Federal) parcel (USDA

Forest Service, 1980). Glacial outwash and terrace deposits are mapped in that vicinity, so it is

likely that the prospect is a sand and gravel deposit. This deposit should be examined to

determine if it extends into the property considered in this exchange. Quaternary deposits

having potential for sand and gravel are plentiful north of the Missouri River and east of the

properties considered for this exchange. 

Only the Pierre Shale is exposed in the study areas and “in general, Pierre shale is considered to

be a poor material for use in constructing highway fills. In many places south and west of the

Missouri River, however, no substitute is readily available (Crandell, 1954).” Crandell

summarizes the resource potential negatively: “Nearly all the bedrock units and surficial deposits

that occur in the quadrangle have been used at one time or another for fill material. In some

cases such use has caused highway fill failure and other engineering difficulties.” 

Based on this assessment, mineral resource potential for locatable, leasable, and salable

commodities on any of the parcels is low.

REFERENCES:

Crandell, D.R., 1954, Geologic map of the Canning Quadrangle, South Dakota: U.S. Geological

Survey Geologic Quadrangle Map GQ-39, scale 1:62,500.

USDA Forest Service, 1980, Fort Pierre National Grassland, South Dakota–Grassland visitors

map: U.S. Geological Survey, scale 1:126,720.

LIST OF ATTACHMENTS:

A. Report request (provided by USDA Forest Service).

B. Exhibit A. Legal description of non-Federal land considered in this exchange (provided

by USDA Forest Service).

C. Exhibit B. Legal description of Federal land considered in this exchange (provided by

USDA Forest Service).

D. Index map showing approximate locations of the land exchange parcels (provided by

USDA Forest Service).

E. Simplified geologic map showing location of parcels. (After Crandell, 1954.)

132
C:\...\locmin\locmin78.wpd 3 April 15, 2004

Attachment A. Report request (provided by U.S. Forest Service)

133
C:\...\locmin\locmin78.wpd 4 April 15, 2004

Attachment B. Exhibit A (provided by U.S. Forest Service)

134
C:\...\locmin\locmin78.wpd 5 April 15, 2004

Attachment C. Exhibit B (provided by U.S. Forest Service).

135
Attachment D. Index map of Missouri Breaks Land Exchange (provided by USDA Forest Service)

Attachment D. Index map showing location of Missouri Breaks Land

Exchange and vicinity (provided by USDA Forest Service).

136
Attachment E. Geologic map of the Missouri Breaks land exchange and vicinity (after Crandell, 1954). 

Qwo, glacial outwash terrace deposit; Kpm, Mobridge 

Member; Kpvc, Virgin Creek 

Member; Kpv, Verendrye 

Member.

Other units shown on the map do not crop out in the area of interest for the land exchange.

Federal Property

Non-Federal Property

44 15'

100 10' 100 5'

o

o o

Qwo Kpvc

Kpv

Kpv

Kpvc

Kpm

Kpm

137
WYOMING

138
C:\...\locmin\locmin77.wpd December 12, 2003

LOCATABLE MINERAL REPORT FOR THE

CITY OF BUFFALO EXCHANGE OFFER,

BLACK HILLS AND BIGHORN NATIONAL FORESTS,

CROOK AND JOHNSON COUNTIES, WYOMING

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

December 12, 2003

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasis is primarily on locatable mineral resources. Leasable and salable resources are covered only if

they appear in the above documents. Mineral resource assessments are subjective: the opinions expressed

herein are entirely those of the author.

139
C:\...\locmin\locmin77.wpd December 12, 2003

U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

(303) 236-5593

FAX (303) 236-3200

awilson@usgs.gov

December 12, 2003

Mr. Mike Doran

Acting Director, Physical Resources

U.S.D.A. Forest Service

PO Box 25127

Lakewood, CO 80225-0127

Dear Mr. Doran:

This report is in response to your November 17 request for information on locatable mineral

resources in the Tie Hack Reservoir land exchange proposal in which the City of Buffalo,

Johnson County, Wyoming, has offered certain non-Federal lands within the Black Hills

National Forest in exchange for Federal lands within the Bighorn National Forest. 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in Exhibits

A and B, which were included with your request. These lands comprise approximately 418.63

acres in Crook and Johnson Counties, Wyoming.

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: W.C. Day

E.A. du Bray

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin77.wpd 1 December 12, 2003

For the legal location description of lands considered for exchange, refer to Exhibits A and B in

Attachments A and B. The report request is Attachment C. Attachments D and E are simplified

geologic maps showing the location of the Federal and Non-Federal parcels. Attachment F is an

index map showing general location of the land exchange parcels.

Non-Federal Lands

Dugout Gulch Property

Tinton 1:24,000, Tinton 1:62,500, Sundance 1:100,000, Gillette 1:250,000 quadrangles. 

The Dugout Gulch property is approximately 4 mi south of Beulah, Wyoming, in the NW corner

of the Tinton 1:24,000 quadrangle. The area includes the ridge separating Dugout Gulch on the

west from Hospital Gulch on the east. It is mapped (DeWitt and others, 1989, as compiled from

Darton, 1905) as lower Permian and Pennsylvanian Minnelusa Formation (light-brown to red

and gray sandstone, solution breccia, limestone, and shale) overlain by Lower Permian Opeche

Shale (red silty shale) and topped by Lower Permian Minnekahta Limestone (gray to purplishgray, slabby limestone).

No mines, prospects, occurrences, or mining districts are in the immediate vicinity (Wilson and

DeWitt, 1995). At a resource assessment at 1:250,000-scale, the area falls within a large tract

assigned high potential for large bedded deposits of high-calcium limestone and within a tract

assigned low potential for small to medium stratabound deposits of oil and gas (DeWitt and

others, 1986).

 

Federal Lands

Tie Hack Reservoir

Hunter 1:24,000, Buffalo 1:100,000, Sheridan 1:250,000 quadrangles. 

The Tie Hack Reservoir area is about 11 miles west-southwest of Buffalo and 3 to 4 miles east of

the Cloud Peak Primitive area. The reservoir was constructed between 1996 and 1998. The

area surrounding the reservoir is entirely within Archean granite gneiss composed chiefly of

quartz, plagioclase, biotite, and microcline and cut by several northeast-strikinging dikes of

diabase, diorite, or metabasalt (Hinrichs and others, 1990). The Wyoming State map (Love and

Christiansen, 1985, 1:500,000 scale) shows the same outcrop pattern for the early Archean

oldest gneiss complex but describes the unit as layered granitic gneiss that is locally migmatitic. 

There may also be local masses of quartzite, metagraywacke, iron-formation, and other

metasedimentary rocks, and amphibolite and felsic gneiss thought to be volcanic in origin. 

Metamorphism occurred in the Bighorn Mountains more than 3 billion years ago (Love and

Christiansen, 1985). 

No mines or prospects are located in the same Precambrian metamorphic rock unit anywhere in

the vicinity of the reservoir (Wilson and others, 2001). Mineral resource potential for locatable

commodities in the vicinity of the reservoir is low.

141
C:\...\locmin\locmin77.wpd 2 December 12, 2003

REFERENCES:

DeWitt, Ed, Redden, J.A., Buscher, David, and Wilson, A.B., 1989, Geologic map of the Black

Hills area, South Dakota and Wyoming: U.S. Geological Survey Miscellaneous

Investigations Series Map I-1910, scale 1:250,000.

DeWitt, Ed, Redden, J.A., Wilson, A.B., and Buscher, David, 1986, Mineral resource potential

and geology of the Black Hills National Forest, South Dakota and Wyoming, with a

section on Salable commodities, by John S. Dersch: U.S. Geological Survey Bulletin

1580, 135 p., 4 plates.

Hinrichs, E.N., Kent, B.H., and Pierce, F.W., 1990, Bedrock geologic map and coal sections in

the Buffalo 30' x 60' quadrangle, Johnson and Campbell Counties, Wyoming: U.S.

Geological Survey Miscellaneous Investigations Series Map I-1923-A, scale 1:100,000.

Love, J.D., and Christiansen, A.C., 1985, Geologic map of Wyoming: U.S. Geologic Survey

State Geologic Map, 3 plates, scale 1:500,000.

Wilson, A.B., and DeWitt, Ed, 1995, Maps showing metallic mineral districts and mines in the

Black Hills, South Dakota and Wyoming: U.S. Geological Survey Miscellaneous

Investigations Series Map I-2445, scale 1:100,000.

Wilson, A.B., Klein, T.L., and Heran, W.D., 2001, Databases and simplified geology for

mineralized areas, claims, mines, and prospects in Wyoming: U.S. Geological Survey

Open-File Report 01-497 [http://pubs.usgs.gov/of/2001/ofr-01-0497/].

LIST OF ATTACHMENTS:

A. Exhibit A. Legal description of non-Federal land considered in this exchange (provided

by U.S. Forest Service).

B. Exhibit B. Legal description of Federal land considered in this exchange (provided by

U.S.D.A. Forest Service).

C. Report request (provided by U.S.D.A. Forest Service).

D. Simplified geologic map showing location of non-Federal parcel. (After DeWitt and

others, 1989.)

E. Simplified geologic map showing location of Federal parcel. (After Hinrichs and others,

1990.)

F. Index map showing approximate locations of the land exchange parcels.

142
C:\...\locmin\locmin77.wpd 3 December 12, 2003

Attachment A. Exhibit A (provided by U.S. Forest Service)

143
C:\...\locmin\locmin77.wpd 4 December 12, 2003

Attachment B. Exhibit B (provided by U.S. Forest Service)

144
C:\...\locmin\locmin77.wpd 5 December 12, 2003

Attachment C. Report request (provided by U.S. Forest Service).

145
Approximate location of 

Dugout Gulch property

PIPm MDpe

Qal

Qt

0 2.5 5

miles

146
2.5 5

miles

0

approximate location of Tie Hack Reservoir property

147
Tie Hack Reservoir

Buffalo

Sheridan

Gillette

Casper

Douglas

Wh

Rock Springs

Kemmerer

Afton

Jackson

Pinedale

Lander

Riverton

Thermopolis

Cody

Powell

Greybull

Lovell

Laramie

Rawlins

Green River

Evanston

Park Park

Campbell Campbell Campbell

Big Horn Big Horn Big Horn

Sheridan Sheridan Sheridan

Teton Teton Johnson Johnson Johnson

Washakie Washakie Washakie Hot Springs Hot Springs Hot Springs

Fremont Fremont Fremont

Natrona Natrona Natrona

Converse Converse Converse

Sublette Sublette Sublette

Lincoln Lincoln Lincoln

Sweetwater Sweetwater Sweetwater Carbon Carbon Albany Albany

Uinta Uinta

Worland

Attachment F. Approximate location of Dugout Gulch and Tie Hack Reservoir land exchange parcels.

8

148
C:\...\locmin\locmin85.wpd January 19, 2003

LOCATABLE MINERAL REPORT FOR THE

COW CREEK (Thomson) LAND EXCHANGE OFFER,

THUNDER BASIN NATIONAL GRASSLAND,

MEDICINE BOW NATIONAL FOREST,

CONVERSE COUNTY, WYOMING

By

Anna B. Wilson

U.S. Geological Survey

Administrative Report

January 19, 2005

The following report is based on information contained in USGS mineral resource and commodity files,

mineral information databases (MRDS and MAS), and on reports and maps available in the USGS library.

These data are occasionally augmented with unpublished documents, personal communications, and

professional experiences. No field studies or on-site visits were performed in preparing this report.

Emphasisis primarily on locatable mineralresources. Leasable and salable resources are covered only if they

appear in the above documents. Mineral resource assessments are subjective: the opinions expressed herein

are entirely those of the author.

149
C:\...\locmin\locmin85.wpd January 19, 2003

U.S. Department of the Interior

U.S. Geological Survey

Box 25046, MS 964

Denver Federal Center

Denver CO, 80225

(303) 236-5593

FAX (303) 236-3200

awilson@usgs.gov

January 19, 2005

Randall Karstaedt

Director, Physical Resources

U.S.D.A. Forest Service

P.O. Box 25127

Lakewood, CO 80225-0127

Dear Mr. Karstaedt:

This report is in response to your January 11 request for information on locatable mineral

resources in the Cow Creek land exchange proposal in which David R. Thomson has offered

certain non-Federal lands within the Thunder Basin National Grassland in exchange for Federal

lands also within the Thunder Basin National Grassland. 

In accordance with our long-term working agreement under Public Law 86-509, we are

providing you with a report on the locatable mineral resources on the lands described in Exhibits

A and B, which were included with your request. These lands comprise approximately 1,320.52

acres in Converse County, Wyoming.

Sincerely yours,

Anna B. Wilson, Geologist

Mineral Resources Program, Central Region

Copies: C.J. Nutt

N. Hollenkamp

J.S. Dersch
C:\...\locmin\locmin85.wpd 1 January 19, 2003

The report request is Attachment A. For the legal location description of lands considered for

exchange, exclusive of reservations or outstanding rights, refer to Exhibits A and B in

Attachment B. Attachment C is a simplified geologic maps showing the location of the Federal

and Non-Federal parcels.

Federal and Non-Federal Lands

Cow Creek Land Exchange

Pinacle Rocks, Split Hill 1:24,000; Lance Creek 1:100,000; Newcastle 1:250,000 quadrangles. 

All of the properties considered for exchange are on the southeastern flank of the Powder River

Basin. The geology is mapped at State-scale as the lower part of the Lebo Member of the

Tertiary Fort Union Formation. The Lebo Member is primarily dark-gray clay shale and

concretionary sandstone (Love and Christiansen, 1985). Attachment C is a simplified geologic

map after Green and Drouillard (1994) and Wilson and others (2001) showing the location of the

parcels in the Fort Union Formation. 

No mines, prospects, occurrences, or mining districts for locatable commodities are in the

immediate vicinity (Wilson and others, 2001). Mineral resource potential for locatable

commodities on all of the parcels considered in this exchange is equally low. 

REFERENCES:

Green, G.N., and Drouillard, P.H., 1994, The digital geologic map of Wyoming in ARC/INFO

format: U.S. Geological Survey Open-File Report 94-0425.

[http://pubs.usgs.gov/of/1994/ofr-94-0425]

Love, J.D., and Christiansen, A.C., 1985, Geologic map of Wyoming: U.S. Geologic Survey

State Geologic Map, 3 plates, scale 1:500,000.

Wilson, A.B., Klein, T.L., and Heran, W.D., 2001, Databases and simplified geology for

mineralized areas, claims, mines, and prospects in Wyoming: U.S. Geological Survey

Open-File Report 01-497. [http://pubs.usgs.gov/of/2001/ofr-01-0497/]

LIST OF ATTACHMENTS:

A. Report request (provided by U.S.D.A. Forest Service).

B. Exhibits A and B. Legal description of lands considered in this exchange (provided by

U.S. Forest Service).

C. Simplified geologic map showing location of parcels. (After Wilson and others, 2001.)

151
C:\...\locmin\locmin85.wpd 2 January 19, 2003

Attachment A. Report request (provided by U.S. Forest Service). 

152
C:\...\locmin\locmin85.wpd 3 January 19, 2003

Attachment B. Exhibits A and B (provided by U.S. Forest Service)

153
C:\...\locmin\locmin85.wpd 4 January 19, 2003

Attachment C. Simplified geologic map showing approximate

location of lands considered for exchange. (After Wilson and

others, 2001.)

154
155

U.S. Department of the Interior 

Gale A. Norton, Secretary 

U.S. Geological Survey 

P. Patrick Leahy, Acting Director 

U.S. Geological Survey, Reston, Virginia 2006 

For product and ordering information: 

World Wide Web: http://www.usgs.gov/pubprod 

Telephone: 1-888-ASK-USGS 

For more information on the USGS—the Federal source for science about the Earth, 

its natural and living resources, natural hazards, and the environment: 

World Wide Web: http://www.usgs.gov 

Telephone: 1-888-ASK-USGS 

Any use of trade, product, or firm names is for descriptive purposes only and does not imply 

endorsement by the U.S. Government. 

Although this report is in the public domain, permission must be secured from the individual 

copyright owners to reproduce any copyrighted material contained within this report. 

This report has not been reviewed for stratigraphic nomenclature.