ARIZONA ~ ' ) K' Mountain ' ' Mgman Pass
GUIDEBOOK SERIES Volume 1
PROTEROZOIC ORE DEPOSITS OF THE SOUTHWESTERN U.S. Ed .DeWitt ~ r------, ' I ~'~:s Veg~J I ARIZONA ~ ' ) K' Mountain ' ' mgman Pass
I ( Phoenix l_ ,.J '--...._ ------______J Guidebook Prepared for Society of Economic Geologists Field Conference - 22-24 October 1987 Series Editor: Tommy B. Thompson SOCIETY OF ECONOMIC GEOLOGISTS CONTENTS
FIRST DAY PAGE
Introduction ...... • ...... • . . . . . 1
Road Log from las Vegas, Nevada, to Mountain Pass, California ...... • ...... • ...... • . . 2
Surface Excursions, Mountain Pass Area ...... •...... 12
Road Log from Mountain Pass, California, to Oatman, Arizona ...... 21
Road Log from Oatman, Arizona, to Kingman, Arizona .... 39
Rare-Earth Mineral Deposits of the Mountain Pass District, San Bernardino County, California (excerpts reprinted from U.S. Geological Survey Professional Paper 261) ...... 46
Geochemistry of Shonkinites, Syenites, and Granites Associated with the Sulfide Queen Carboname Body, Mountain Pass, California (excerpts from Crow, 1984) ...... •.....•...... 53
U-Th-Pb and 40 Arp9 Ar Dating of the Mountain Pass Carbonatlte and Alkalic Igneous Rocks, South eastern California (reprinted from Geological Society of America Abstracts with Programs, v. 19, no. 7 .•...... •. 55
SECOND DAY
Introduction ...... •...... •...... 56
Road Log from Kingman, Arizona, to Bagdad, Arizona ... 57
Road Log from Bagdad, Arizona, to the Black Pearl Mine ...... 73
Road Log from Bagdad, Arizona, to the Bruce Mine ...... 77
Road Log from Bagdad, Arizona, to Prescott, Arizona ..... 83 CONTENTS (cont.)
SECOND DAY (cont.) PAGE
Field Guide to the Black Pearl Tungsten Mine Area, Yavapai County, Arizona, by Christopher Schmitz and Donald M. Burt ...... •. 97
Geochemistry of the Alteration Pipe at the Bruce Cu-Zn Volcanogenic Massive Sulfide Deposit, Arizona (excerpts reprinted from Economic Geology, v. 79) ...... •...... 106
Field Guide to Early Proterozoic Strata that Host Massive Sulfide Deposits at Bagdad, Arizona (excerpts reprinted from Geological Society of America, Rocky Mountain Section Guidebook, Flagstaff, 1986) ...... •...... 112
Massive Sulfide Deposts at Bagdad, Arizona; End-Products of a Recurrent Early Proterozoic Volcanic Hydrothermal System, by T.J. Connelly C.M. Conway ...... 116
THIRD DAY
Introduction ...... 124
Road Log from Prescott, Arizona, to Iron King Mine ...... 125
Road Log from Iron King Mine to Huron-Montezuma Prospect ...•...... 131
Road Log from Huron-Montezuma Prospect to Bell Ranch Prospect ...... 136
Road Log from Bell Ranch Prospect to Phoenix, Arizona ...... 143
Early Proterozoic Gold Mineralization, Alteration Assemblages, and Geochemistry of the Huron Montezuma Prospect, Yavapai County, Arizona, by P.F. O'Hara ...... 161
Geochemistry of Early Proterozoic Felsic Metavolcanic Rocks Associated with Gold Mineralization at the Bell Ranch Prospect, Yavapai County, Arizona, by P.F. O'Hara ...... 167
ii CONTENTS (cont.)
THIRD DAY (cont.) PAGE
Geology and Gold Mineralization at the Early Proterozoic Bell Ranch Prospect, Yavapai County, Arizona, by M.M. Swan ...... 169
Lnhological, Structural, Chemical and Mineralogical Patterns in a Precambrian Stratiform Gold Occurrence, Yavapai County, Arizona (excerpts reprinted from Process Mineralogy, Conference Proceedings, 1981) ...... 174
Precious Metal Content of Protreozoic Massive Sulfide Deposns in Arizona (reprinted from Geological Society of America Abstracts w~h Programs, v. 18, no. 5) ...... 177
REFERENCES CITED ...... 178
iii ITINERARY
DATE TIME PROGRAM
Thursday, October 22 7:00-8:00 a.m. Drive from Las Vegas to Mountain Pass
8:00a.m. to Visit Mountain Pass mine area 1:00 p.m. (STOPS 1, 2, and 3)
1 :00-2:00 p.m. Lunch at Mountain Pass
2:00-5:00 p.m. Drive from Mountain Pass to Oatman, with brief stop at Colorado River (STOP 4)
5:30-7:00 p.m. Supper and refreshments in Oatman (STOP 5)
7:00-8:00 Slide show on epithermal gold deposRs, Oatman area
8:00-9:00 p.m. Drive to Kingman. Night at Wayfarers Inn, Kingman
Friday, October 23 7:00a.m. Breakfast In Kingman
8:00-10:00 a.m. Drive from Kingman to Bagdad, wRh brief stop at Burro Creek (STOP 1)
10:00 a.m. to Visits to Black Pearl mine and 3:00p.m. Bruce-Old Dick mine areas. Group will separate to go to one of two mines. Lunch break included (STOPS 2, 3
4, and 5)
3:00-5:00 p.m. Drive from Bagdad to Prescott
6:00 p.m. Supper and refreshments in Prescott. Night at Prescottonian Motel, Prescott
iv ITINERARY (cont.)
DATE TIME PROGRAM
Saturday, October 24 7:00a.m. Breakfast In Prescott
8:00-8:30 a.m. Drive from Prescott to Iron King mine
8:30-9:30 a.m. Overview of geology and ore deposits In Prescott area (STOP 1)
9:30-10:00 a.m. Drive from Iron King mine to Huron-Montezuma prospect
10:00-12:00 a.m. Visit Huron-Montezuma prospect (STOPS 2, 3, AND 4}
12:00 a.m. to Drive to Bell Ranch prospect 1:00 p.m.
1 :00-2:00 p.m. Lunch at Bell Ranch prospect
i 2:00-4:00 p.m. Visit Bell Ranch prospect I (STOPS 5 AND 6}
4:00-6:00 p.m. Drive from Mayer to Phoenix, with brief stop at Sunset Point Rest Area (STOP 7). Field trip ends in Phoenix
ACKNOWLEDGMENTS
Special thanks are extended to C.H. Thorman and R.B. Taylor, who helped to edit and print, respectively, this paper. Margaret Clemensen and Deborah Walsh DeWitt helped to assemble various parts of the paper. M.M. Swan and S.J. Reynolds supplied unpublished geologic maps that were compiled for use in the figures.
v FIGURES (cont.)
NUMBER PAGE
37. Open pit of the Bagdad mine and lawler Peak ...... 78
38. Geologic map of the Bruce mine area .....•...... 80
39. Weaver Mountains and Tertiary volcanic rocks at Ritter Peak ...... 86
40. Martin Mountain and Thompson Valley north of Hnlside, Arizona ...... 87
41. Kirkland Peak northwest of Kirkland, Arizona ...... 88
42. Sierra Prieta and West Spruce Mountain southwest of Prescott ...... 89
43. Geologic map of the area along U.S. Highway 93 and Arizona Highway 69 from Kirkland Junction to Mayer, Arizona ...... 90
44. Zonla mine and Weaver Mountains east of Yarnell ...... 93
45. Seal Mountain, Wades Butte, and the valley of the Hassayampa River near Wagoner ...... 94
46. Towers Mountain and Horse Mountain in the southern Bradshaw Mountains ...... 95
47. Granite Mountain northwest of Prescott, Arizona ...... 126
48. Black Hills and Hickey Mountain ...... 130
49. Discovery outcrops at the I ron King mine ...... 131
50. Geologic map of the Huron-Montezuma area ...... 132
51. Quarry in metarhyolite northeast of Mayer, Arizona ...... 138
52. Geologic map of the Bell Ranch prospect ...... 140
53. Brady Butte west of Mayer, Arizona ...... 144
54. Towers Mountain and Tuscumbia Mountain in the central Bradshaw Mountains ...... 145
55. Geologic map of the area along Interstate Highway 17 from Cordes Junction to New River, Arizona ...... 146
viii FIGURES (cont.)
NUMBER PAGE
56. Twin Peaks northeast of Horsthief Basin . • . • ...... 149
57. Mount Union, Brady Butte, and Townsend Butte from Black Mesa .•...... •...... 151
58. DeSoto mine and Bland Hill from Black Mesa •...... •.. 152
59. New River Mountains and Moore Gulch shear zone ...... 154
60. Southern Bradshaw Mountains and Black Canyon schist belt ...•...... 155
61. Geologic map of the area along Interstate Highway 17 from the Wickenburg Highway to the South Mountains . . 158
ix