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Norman J. Page

Publications and source records attributed to Norman J. Page.

31 records · Page 2Linked to original sources
USGS1978

Implications of the petrochemistry of palladium at Iron Canyon, Lander County, Nevada

Approximately one-half of the 270 samples from the Iron Canyon area, Nevada, analyzed for platinum-group metals, contain measurable amounts of palladium in the 0.001- to 0.02-part per million range with an average of 0.0034 ppm. The rocks include lower Paleozoic sedimentary and volcanic rocks, Tertiary granitic porphyries, and breccia, all of which exhibit various degrees of hydrothermal alteration. Fault-related iron oxides and vein quartz are also present. The area lies astride the outermost fringes of the zone of dispersed alteration visible in outcrops around the middle Tertiary porphyry-copper system at Copper Canyon, Nevada. At Iron Canyon, the palladium concentrations greater than 0.003 ppm seem to be spatially related to the Butte fault zone, a north-striking fault system active during the time of porphyry-type mineralization. Palladium contents vary directly with those of mercury, arsenic, strontium, silver, lanthanum, and boron, as well as with lead, gold, and copper in obviously metallized rocks. This relation probably reflects the mobility of palladium during porphyry-type mineralization. However, our study failed to document conclusively the overall introduction of palladium during mineralization. Among the likely sources of palladium are the lower Paleozoic volcanic rocks or fluids equilibrated with magma (s) associated with the middle Tertiary porphyries.

Nevada↗
USGS1977

Some observations that bear on the origin of porphyry copper deposits

Observations at Ray, Ariz., suggest that upper crustal calc-alkaline plutons associated in time and space with the deposit might not have been capable of producing much water by differentiation and that any water released likely had restricted access to the best copper-sulfur sources in the magmas. Observation of concentrations of sulfides around isolated pockets of partially melted rocks below the Stillwater Complex. Mont., suggest to us a variant model of porphyry copper generation that does not require calc-alkaline plutons to be the vessels that transport copper and sulfur to upper crustal sites.

Open-File Report↗
USGS1977

Chromite resources of the podiform chromite deposits and exploration for concealed chromite deposits in the Medford-Coos Bay quadrangles, southwestern Oregon

Exploration models for podiform chromite in the Medford-Coos Bay quadrangles must consider the facts that (1) one deposit occurs for every 5 km 2 of ultramafic outcrop; similarly for a 5 km 3 volume, and (2) the average deposit has a tonnage of 206 tonnes, a volume of 8.9 m 3 and a grade between 43 and 51 percent Cr2O3.

Open-File Report↗
USGS1977

Platinum, palladium, and rhodium in volcanic and plutonic rocks from the Gravina-Nutzotin belt, Alaska

The Gravina-Nutzotin belt of Middle (?) Jurassic to middle Cretaceous sedimentary and volcanic rocks in south and southeastern Alaska includes concentrically zoned ultramafic complexes known to contain platinum-group metals. Previous isotopic, petrologic, and geologic studies suggested a close relation in time and space between the volcanic rocks and the ultramafic complexes. Interpretation of 40 analyses for platinum, palladium, and rhodium in volcanic and plutonic rocks of the belt indicates a strong geochemical correlation between the two groups of rocks and is in support of their being cogenetic either from directly connected magma chambers and flows or indirectly by selective concentration processes from similar mantle material.

Alaska↗
USGS1975

Ore grade, metal production, and energy

Recent resource estimates have been stimulated by national concern over present and pending shortages of energy and mineral resources. Although some believe that the resource base of a commodity is the total amount in the crust, the energy consumption for mining and milling under present technology suggests that grades of the metallic ores have a lower limit when production is assumed to be for common usages. The tonnage required to mine and mill ores to obtain one unit of metal is a hyperbolic function of the grade, and as the tonnage increases hyperbolically, so does the energy consumed. For copper, the hyperbolic relation suggests that deposits with grades below about 0.20-0.25 percent Cu will not be mined to produce metal for common electrical and construction uses. Although the energy used to mine and mill a unit of metal differs from one metal to another, all show the hyperbolic increase in energy consumption as grade decreases.

Journal of Research of the U.S. Geological Survey↗
USGS1973

A Precambrian diamictite below the base of the Stillwater Complex, southwestern Montana

The metasedimentary rocks of Precambrian age below the base of the Stillwater Complex, southwestern Montana, contain a metamorphosed diamictite similar to diamictite in strata of late Precambrian and Early Cambrian age in Canada and the Western United States. The diamictite consists of a quartz-cordierite matrix containing an average 10-15 percent of rock fragments diverse in shape, size, angularity, lithologic types, and textures. The diamictite unit is poorly sorted, crops out discontinuously for 14 miles, and locally has a crude layering containing dropstones. Its origin is debatable, but the rock is suggestive of glacial marine deposition. The minimum age of the diamictite of the complex is 2,750 m.y. from U-Pb determination on zircon of intrusive quartz monzonite, the maximum 3,140 m.y. as determined on zircon from metasedimentary rocks interbedded with the diamictite.

Montana↗
USGS1969

Platinum, palladium, and rhodium analyses of ultramafic and mafic rocks from the Stillwater Complex, Montana

Analyses by a combination fire- assay-solution-optical-emission spectrographic method of 137 rocks from the Stillwater Complex, Mont., indicate that platinum, palladium, and rhodium are preferentially concentrated in chromitite zones. The A chromitite zone (21 samples) has an average of 988.9 ppb (pans per billion, 10 -9 ) Pt, 2290.2 ppb Pd, and 245.9 ppb Rh and reaches a maximum (to date) of 8,000 ppb Pt, 11,000 ppb Pd, and 1,700 ppb Rh.

Montana↗