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In the central York Mountains, carbonate rocks of Lower and Middle Ordovician age and aggregating at least 8,000 feet thick are thrust northward over slate and argillaceous limestone of pre-Ordovician age which were intruded by gabbro in pre-Ordovician time. Normal faults of four distinct systems cut the thrust plates, and...

The uranium, thorium, and potassium content of hydrothermally altered rocks in the vicinity of several copper and copper-lead-zinc deposits in Arizona was determined by chemical analysis. Potassium in the more intensely altered zones is about twice that in unaltered areas. There is no corresponding increase in thorium, so a higher potassium/thorium ratio also results from...

Aconcagua Province is herein divided into three major structural provinces which, for the sake of simplicity, are named the Coastal Cordillera, Central Valley graben, and Andean Cordillera structural provinces to correspond to the three geomorphic provinces recognized farther south. The coastal structural province includes the Coastal Cordillera which is underlain mainly by layered sedimentary and effusive rocks that strike north and dip...

A vacuum‐jacketed metal calorimeter for determining heats of solution in aqueous HF was constructed. The reaction vessel was made of copper and was heavily gold plated. The calorimeter has a cooling constant of 0.6 cal‐deg−1‐min−1, approximately ¼ that of the air‐jacketed calorimeters most commonly used with HF. It reaches equilibrium within 10 min after turning off the heater current. Measurements...

A study of the distribution of copper in transported alluvium on a pediment of the Rocky Range, Beaver County, Utah, undertaken to determine whether known copper deposits in bedrock concealed by alluvium could be detected by geochemical methods, was reported in Geological Survey Research 1960 ( Erickson, R.L., and Marrenzino,...

No abstract available....

A rapid field method for the determination of cold-extractable cobalt in soils and sediments has been developed for use in geochemical prospecting. Readily available cobalt is dissolved by treating the sample with an aqueous ammonium citrate-hydroxylamine hydrochloride solution; the filtered citrate extract is then treated with 2-nitroso1-naphthol to form a...

An uneven erosion surface separates calcareous sedimentary rocks above and vesicular andesite porphyry below at the Guayacan mine of central Chile. Channel-like depressions filled with sedimentary rock flank elongate, stratiform bodies of disseminated copper ore which impregnate the vesicular crests of andesite lava flows. The "channels" lie parallel to and mark the margins of tongues of lava. Erosional features...

A well drilled for geothermal power near Salton Sea in Imperial Valley, Calif., is 5,232 feet deep; it is the deepest well in the world (1962) in a high-temperature hot spring area. In the lower half of the hole temperatures are too high to measure with available equipment, but are...

The composition of nonmarine shales of Cretaceous age that contain less than 1 per cent organic carbon is assumed to represent the inherited minor-element composition of clayey sediments delivered to the Cretaceous sea that occupied the western interior region of North America. Differences in minor-element content between these samples and...

The study of the salt deposits of northern Chile is a cooperative project of the Institute de Investigaciones Geologicas (IIG) of Chile and the United Nations Special Fund and is part of a mineral resources survey, undertaken by these two organizations, of selected regions of northern Chile, during 1960-1963. The...

A method has been developed for the extraction and chemical microanalysis of individual fluid inclusions, or groups of inclusions, in the milligram range. Usable quantitative analyses for Na, K, Ca, Mg, CI, B, and SO* have been obtained of mineral samples containing several milligrams of inclusion fluid, and with increased experimental errors,...

Much of the disagreement over "epigenetic" And "Syngenetic" Deposits Is Semantic; Some Ores And altered rocks are in part syngenetic and in part epigenetic and for them the term "diplogenetic" is proposed. All these terms are primarily time terms related to the contemporaneity of the deposit and the enclosing rock, but...

Microgram quantities of copper, manganese, and zinc, corresponding to concentrations greater than 100 parts per million, were found in milligram quantities of primary inclusion fluid extracted from samples of quartz and fluorite from two types of ore deposits. The results indicate that neutron activation is a useful analytical method for...

A deep geothermal well in California has tapped a very saline brine extraordinarily high in heavy metals and other rare elements; copper and silver are precipitated during brine production. Preliminary evidence suggests that the brine may be pure magmatic water and an active ore-forming solution. Metamorphism of relatively young rocks...

Of 15 or more minor elements in the world's principal river waters only aluminum, iron, manganese, barium and strontium range much over 100 μgl">100 μgl. (parts per billion). Most minor elements range at or below 100 μg1">100 μg1. and have...

The copper districts in the United States (exclusive of Alaska and Hawaii) are shown on the accompanying map. In compiling the map, the estimated total quantity of copper present before mining was used to assign districts to size categories, and both production and reserves are included without distinction as to...

Vanadium is known to occur in soils as vanadates of copper, zinc, lead, uranium, ferric iron, manganese, calcium, and potassium. Vanadium replaces aluminum in clays and occurs in porphyrin complexes in bituminous sediments.Small amounts of vanadium are stimulating to plants; large amounts are toxic. Ten to 20 ppm vanadium in...

Massive and disseminated pyrrhotite-chalcopyrite-pyrite ore replaced a fault zone in Precambrian Carolina Gneiss of Keith (1). Closely following sulfide deposition, vein sulfides and silicates in the wall rock were recrystallized under a rising temperature gradient to coarse-grained unoriented aggregates that contain late pyrite porphyroblasts in pyrrhotite. Boudinage, dilation, and flow structures are common....

Gold, silver, copper, and lead-bearing veins, non-radially zoned, occur just beyond the southern and western margins of the Searchlight, Nevada, quartz monzonite stock. Seven samples of the quartz monzonite and purified individual constituent minerals of the rock, representing apophyses and marginal and interior parts of the intrusive mass, were analyzed petrographically...

The metalliferous deposits of Chile tend to be restricted to well denned metallogenetic provinces, each characterized by a dominant mineral or mineral assemblage. The most important ore deposits are those of copper, iron, silver, gold, and manganese. The primary minerals are few in number and most are simple sulfides and...

A method for the quantitative spectrochemical determination of microgram amounts of 17 minor elements in water is given. The chelating reagents 8-quinolinol, tannic acid, and thionalide are utilized to concentrate traces (1 to 500 μg.) of aluminum, cobalt, chromium, copper, iron, gallium, germanium, manganese, nickel, titanium, vanadium, bismuth, lead, molybdenum,...