Au-Ag polymetallic mineralization within tectonically weak zones along the southwestern edge of the Colorado Plateau

Conference · Thu Apr 01 04:00:00 EST 1993 · Geological Society of America, Abstracts with Programs; (United States)

OSTI ID:5020592

Wenrich, K J; Silberman, M L ^[1]

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1. Geological Survey, Denver, CO (United States)

The Music Mountain mining district lies at the base of the Grand Wash Cliffs, a major fault-line scarp along the Grand Wash fault, which marks the SW margin of the Colorado Plateau. Nearly vertical Au-Ag polymetallic quartz veins parallel, and are in contact with, altered diabase and granite porphyry dikes that cut Proterozoic granite, schist, and gneiss. The gold-bearing veins range in thickness from an inch to several feet and contain significant amounts of sulfide minerals. Diabase dikes and quartz veins in the district and to the north consistently strike N42[degree]W to N57[degree]W, which is one of the most prevalent fracture orientation throughout NW Arizona. In the Gold Basin-Lost Basin districts to the north, the Au occurs in such pegmatite-quartz veins that strike NE. Thirty miles east along Diamond Creek, quartz veins and diabase dikes strike N45[degree]E and are associated with Au and Ag anomalies in stream-sediments and panned concentrates. To the west major Au-Ag polymetallic quartz veins of the Wallapai mining district show consistent strikes from N30[degree] to 60[degree]W. K-Ar ages of hydrothermal alterations of 4 NW oriented diabase dikes that have quartz veins along them, range from 935 [+-] 35 to 755 [+-] 21 Ma. Sericite from altered granite porphyry, adjacent to a mineralized vein, gave a K-Ar age of 72 [+-]2 Ma. All geochemical sites (within a 1,000 mi[sup 2] area) determined to be anomalous in Au lie within 2 mi of either the Grand Wash or Hurricane faults. The Hurricane and Grand Wash faults, major Precambrian fault zones that were reactivated in the Phanerozoic, appear to be good exploration targets for Au-rich quartz veins associated with pegmatite or diabase dikes, many of which may be buried beneath the thick alluvium of Hualapai Valley.

• OSTI ID: 5020592
• Report Number(s): CONF-9305259--
• Conference Information: Journal Name: Geological Society of America, Abstracts with Programs; (United States) Journal Volume: 25:5
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
AGE ESTIMATION
ALKALI METAL ISOTOPES
ARGON ISOTOPES
ARIZONA
BASALT
COLORADO PLATEAU
DEVELOPED COUNTRIES
DIABASES
ELEMENTS
GEOLOGIC DEPOSITS
GEOLOGIC FAULTS
GEOLOGIC FRACTURES
GEOLOGIC STRUCTURES
GEOLOGY
GOLD
GOLD ORES
GRANITES
HYDROTHERMAL ALTERATION
IGNEOUS ROCKS
ISOTOPE DATING
ISOTOPES
METALS
MINERALIZATION
MOUNTAINS
NORTH AMERICA
ORES
PLUTONIC ROCKS
POTASSIUM ISOTOPES
ROCKS
SILVER
SILVER ORES
TRANSITION ELEMENTS
USA
VOLCANIC ROCKS