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Norman J. Page

Publications and source records attributed to Norman J. Page.

At least 37 records · Page 2Linked to original sources

Palladium, platinum, and rhodium concentrations in mafic and ultramafic rocks from the Zhob Valley and Dargai complexes, Pakistan

The Zhob Valley and Dargai complexes, Pakistan, consist of harzburgite and dunite tectonites containing chromite deposits, pyroxenite, wehrlite, and gabbro. Both are ophiolite complexes. Palladium, platinum, and rhodium were found in concentrations of up to 170, 200, and 22 parts per billion, respectively. Average concentrations for both complexes and all rock types collected are 28 ppb palladium, 33 ppb platinum, and 9 ppb rhodium. The Pt:Pt+Pd ranges from 0.41 to 0.67 and averages 0.57. The concentration levels and ratios of these metals are similar to other alpine ultramafic bodies that have been analyzed by modern techniques.

Zhob Valley complex↗

Palladium, platinum, and rhodium concentrations in mafic and ultramafic rocks from the Kizildag and Guleman areas, Turkey, and the Faryab and Esfandagheh-Abdasht areas, Iran

The Kizildag and Guleman areas, Turkey, and the Faryab and Esfandagheh-Abdasht areas, Iran, have produced chromite from ophiolite complexes consisting of harzburgite tectonite, dunite tectonite containing chromitite, pyroxenite, wehrlite, and gabbro. Forty-six samples from these complexes were analyzed in order to investigate the possibility of platinum-group metals being present that could be produced as byproducts. The results, however, indicate concentrations of palladium, platinum, and rhodium ranging up to 46 ppb (parts per billion), 55 ppb, and 24 ppb, respectively. The concentration levels and ratios of these metals are similar to other alpine ultramafic bodies that have been analyzed by modern analytical techniques. Ten samples from massive sulfide deposits in the Gunes and Ergani-Maden areas, Turkey, and the Sheikh Ali mine, Iran, were analyzed also. The results of the analysis suggests a low potential for byproduct palladium, platinum, and rhodium production in these ophiolite-associated massive sulfide deposits. The four ultramafic and mafic areas in Turkey and Iran under consideration have, and are, producing in 1978 chromite from podiform chromitites in alpine-type complexes. Because of the known association of chromitites and platinum-group metals, a collection of chromitites was made to check their palladium, platinum, and rhodium content to determine if economic concentrations might exist. Also, inasmuch as such rocks are thought to represent parts of the oceanic crust and upper mantle, data on platinum-group elements from these rocks can provide information to design geochemical models for the distribution of these elements. During the field excursions of the CENTO Working Group on Volcanic and Intrusive Rocks and Their Associated Ore Deposits, the Kizildag and Gunes areas, Turkey, were sampled in 1974 and the Guleman area, Turkey; Faryab and Esfandagheh-Abdasht areas, Iran, were sampled in 1975. In addition, samples of massive sulfide ores from the Ergani-Maden area, Turkey, were also collected for analysis, and the results included here. In this report the geologic framework of these areas is briefly examined as a background for interpreting the concentrations of palladium, platinum, and rhodium in the chromitites and ultramafic and mafic rocks. Comparisons of these analyses with analyses from other areas containing similar rocks show few differences in concentration or proportions of these three platinum-group metals.

Open-File Report↗

Differentiation of the sulfides in the Basal Zone of the Stillwater Complex, Montana

Chemical leaching and analysis of the sulflde portion of rocks from a section of the Basal zone of the Stillwater Complex demonstrate that mole fractions of nickel, copper, cobalt, and sulfur in the sulfldes show trends and repeating patterns when plotted against stratigraphic position. These patterns are attributed to differentiation of immiscible sulflde liquids probably in response to differentiation of basaltic magma. Changes in composition of the immiscible sulflde liquids could most readily take place during the collection of the sulflde from the basaltic magma or during the crystallization of the sulflde liquid to the present assemblages of minerals.

Montana↗

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↗

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↗

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↗

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↗

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↗

Mineral resource potential of the Stillwater Complex and adjacent rocks in the northern part of the Mount Wood and Mount Douglas quadrangles, southwestern Montana

The Stillwater Complex contains the largest potential chromite and platinum metal resources and second largest nickel resources in the United States. The Ultramafic zone has produced about 900,000 long tons of chromite concentrate and contains unmined reserves equivalent to 2,520,000 long tons of Cr2O3. Nickel and copper sulfide minerals that occur in the Basal zone and adjacent hornfelsed metasedimentary rocks represent one of the largest nickel potentials in the United States---a known reserve of 150 million tons of 0.25 percent nickel and 0.25 percent copper. The complex has been estimated to contain the largest potential source of platinum metals in the United States---possibly over 150 million troy ounces in the lower chromite zones and the Basal zone. In addition, the anorthosites in the Banded and Upper zones are reported to represent a potential alumina resource of almost 2 billion tons. An iron-formation also is present in the adjacent Precambrian metasedimentary rocks, and a coal bed is present in the Upper Cretaceous Eagle Sandstone nearby. The eventual utilization of these resources depends on the availability of large quantities of energy, and thus they may not be recovered unless new sources of energy or new recovery techniques are developed.

Circular↗

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↗