Road Log from Prescott, Arizona, to Iron King Mine: 17.8 miles
Published:January 01, 1987
0.0 Prescottonian Motel, Prescott. Turn right onto Gurley Street and Arizona State Highway 69 to Phoenix. On the left is Yavapai College and, behind it, the U.S. Veterans Hospital at old Fort Whipple. The large construction project on top of the fanglomerate-capped hill to the northeast is a Sheraton Hotel under construction.
0.2 Intersection with U.S. Highway 89 north to Ash Fork. The left turn goes along Granite Creek and north through the Granite Dells, a picturesque area of granite spires underlain by the Dells Granite (fig, 43), a 1400±15 Ma (Silver and others, 1981) uranium-rich leucogranite (Anderson, in press). Stay to the right, on Arizona Highway 69 to Phoenix. Highway crosses the wash of Government Canyon. Roadcuts on the left beneath the Sheraton Hotel are Tertiary fanglomerate that locally overlies the 1740±15 Ma Government Canyon Granodiorite exposed in the beveled roadcuts. As the highway climbs the small hill past the Sheraton Hotel, we are crossing the Yavapai Indian Reservation, a 4 mi2 tract of land on the northeast edge of Prescott. Roadcuts are in Government Canyon Granodiorite. View to the left at 9:00 down the small gully if of exposures of the Early Proterozoic Prescott Granodiorite across Granite Creek.
0.8 Chaparral-covered hillside to the right underlain by Government Canyon Granodiorite and Early Proterozoic gabbro. Large hill to the right is Badger Mountain, composed entirely of this gabbro.
1.0 Roadcuts on right in Government Canyon Granodiorite. Hills to the left at 9:00 to 12:00 are Tertiary fanglomerate. View behind and
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.