Road Log from Bagdad, Arizona, to the Black Pearl Mine: 16.5 miles
Published:January 01, 1987
0.0 Copper Plaza in Bagdad, Arizona. Proceed east on Arizona Highway 96 toward Hillside, Arizona.
0.1 Intersection of North Lindahl Road and Arizona Highway 96. Turn left (north). A small Bell Telephone building is on the left as you proceed north; the Bagdad Fire Station is on the right.
0.7 Roadcuts in Hillside Mica Schist intruded by aplite-pegmatite. Sanders Mesa on the left at 9:00. One-half mile farther, pass Faye's Pizza Parlor on the right.
1.7 Turnoff to the left to the Bagdad landfill. Proceed straight ahead on the paved road. Outcrops to the right and on Granite Mountain at 1:30 are light-colored Early Proterozoic aplite-pegmatite, which intrudes Hillside Mica Schist.
2.1 Prominent gray peak, straight ahead in the distance, is Blue Mountain. The pluton contains considerable magnetite, and stand out as an aeromagnetic high (Dempsey and others, 1963; Aero Services, 1983).
2.9 Trailer park on right.
3.1 Pavement ends. “Y” in the road; take the heavily traveled fork to the left that climbs to the top of Nelson Mesa.
3.4 View of Blue Mountain, elev. 5,550 ft, which is underlain by a Laramide pluton that is similar in composition to the diorite porphyry dike swarm associated with the porphyry copper deposit west of the town of Bagdad (Anderson and others, 1955). Big Shipp and Little Shipp Mountains are at 1:00, and 2:00 to 2:30, respectively, in the distance. Both peaks are composed of aplite-pegmatite.
3.9 Top of Nelson Mesa. “Y” in the road at construction site. Stay to the
Figures & Tables
Proterozoic Ore Deposits of the Southwestern U.S.
This field conference of the Society of Economic Geologists, held in conjunction with the 1987 Annual Meeting of the Geological Society of America in Phoenix, Arizona, investigates various Proterozoic ore deposits in southeastern California and western and central Arizona. The trip starts in Las Vegas, Nevada, and ends in Phoenix, Arizona. Although Proterozoic ore deposits and geology are emphasized, the field trip traverses a variety of tectonic provinces, each containing ore deposits of various ages. Many geologic features and ore deposits that are not Proterozoic in age will be discussed during the course of the trip, but no stops will be made to investigate any of these, features.
The morning part of the trip starts in the Mesozoic foreland fold and thrust belt of Nevada and southeastern California, goes just east of the Mesozoic batholith belt of California, and ends in crystalline basement containing Early and Middle Proterozoic metamorphic and plutonic rocks. Within this basement is exposed the Middle Proterozoic Mountain Pass Carbonatite deposit, the largest source of rare-earth elements in the world. The Mountain Pass Carbonatite will be the focus of our morning stops.
The afternoon part of the trip crosses Early Proterozoic high-grade metamorphic rocks and plutonic rocks east of Mountain Pass. Ore deposits noted along the afternoon portion of the trip include middle Tertiary epithermal, gold-rich veins at Searchlight, Nevada, and disseminated gold deposits in Tertiary volcanic rocks near Hart Peak in the New York Mountains. The trip continues across the Colorado River trough along the border of California and Arizona, where crystalline basement and its cover of Tertiary volcanic rocks and plutons have been greatly extended along listric normal faults and low-angle detachment faults. The afternoon part of the trip ends in Oatman, Arizona, a district famous for its middle Tertiary epithermal, gold-rich deposits. The ore deposits at Oatman will be the subject of a slide show and talk after supper on the first night of the trip.
The first day ends with an evening drive across a middle Tertiary volcanic pile near Oatman. The first night will be spent in Kingman, Arizona.
Assemble at the Las Vegas Convention Center, south of the Hilton Hotel. Take any main street south to Tropicana Avenue. Turn west on Tropicana, past the Las Vegas Strip, and continue to Interstate Highway 15. Turn south on Interstate 15 toward Mountain Pass, California. Mileage starts at 0.0.