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New deposits of lead, zinc, and silver were found in a large altered zone 18 miles long and 2 to 5 miles wide near Quartz Creek west of Granite Mountain in the eastern Seward Peninsula, Alaska. New deposits of molybdenum, bismuth, and silver were found associated with a previously reported...

Sedimentary and volcanic rock units of Paleozoic and Mesozoic age, faults, and elongate bodies of intrusive rock, particularly serpentinites, have a dominant northeasterly trend in an area northwest of the Chulitna River between Eldridge Glacier and Bull River. The serpentinites locally contain abnormal (as much as 0.5 percent) concentrations of...

A simple and rapid method of determining casing length and permeable zones in wells tapping bedrock can be useful to well drillers and hydrologists. A device consisting of a galvanometer, a reel of insulated wire, and a copper...

The U.S. Geological Survey began gravity surveys in Alaska ten years ago with local surveys in the Copper River and Tanana Basins. Shortly before the 1963 AGU gravity symposium [Barnes, 1965], the emphasis shifted from local surveys to the preparation of a reconnaissance gravity map of the whole state with...

An area northwest of the Chulitna River in west-central Alaska Range locally shows local anomalous concentrations of gold, silver, arsenic, copper, zinc, and lead in stream-sediment samples. Most stream sediments showing anomalous concentrations of metals can be correlated with either known or newly discovered deposits or occurrences described in Circular...

Gold content was determined, by neutron-activation analysis, in samples from a drill core through the Great Lake sheet, Tasmania, a differentiated tholeiitic dolerite. The gold content of parts of the core seems to be related to the mafic index. The variation of...

Palladium and platinum are determined by atomic absorption after fire-assay concentration into a gold bead. The limit of determination is ~0·06 ppm in a 20-g sample. Serious depressive interelement interferences are removed by buffering the solutions with a mixture of cadmium and copper sulphates with cadmium...

Complex ore deposits are spatially associated with granitic bodies of Precambrian age in the Lake George area, Colorado. They include greisens that contain high concentrations of beryllium and subordinate amounts of tin, tungsten, and other metals associated with the Redskin Granite. Scheelite deposits in calc-silicate rocks and greisen deposits near Tappan Mountain...

Above-normal precipitation in 1954, 1956, and 1957 caused the water surface of Devils Lake to rise to an altitude of 1,419.3 feet, its highest in 40 years. Nearly all the water entering the lake flowed through Big Coulee, and about three-fourths of that inflow was at rates greater than 100...

Reconnaissance of the Jabal Khida quadrangle shows that granite and granodiorite (unit gg), biotite and hornblende granite (unit gr) and alkalic and paralkalic granit (unit gp) divisions for granites seems valid, but that two ages of metamorphic and extrusive rocks are mapped as the Halaben formation (unit ha/hc). Semiquantitative analyses of...

An area of 10,000 sq. km between Bi'r Idimah and Wadi Haraman in southern Saudi Arabia was investigated for mineral deposits during the period May 8, 1965, to June 27, 1965. At least 25 different minerals and industrial rocks occur in the area, but of these materials only asbestos seems...

The Golden Zone mine area, in the upper Chulitna district, is underlain mainly by siltstone and tuff, volcanic conglomerate and breccia, and limestone. These rocks were invaded, probably in the Tertiary, by dikes and a small stock of porphyry. The ore deposits of the area are the Golden Zone breccia...

The Mill Canyon area is in the eastern part of the Cortez window of the Roberts Mountains thrust belt in the Cortez quadrangle, north-central Nevada. Gold and silver ores have been mined from fissure veins in Jurassic quartz monzonite and in the bordering Wenban Limestone of Devonian age. Geochemical data...

Platinum-group metals in the Medicine Bow Mountains were first identified by W. C. Knight in 1901. In the Medicine Bow Mountains, these metals are commonly associated with copper, silver, or gold in shear zones that cut a series of mafic igneous and metamorphic rocks. At the New Rambler mine, where...

The great earthquake that struck Alaska about 5:36 p.m., Alaska standard time, Friday, March 27, 1964 (03:36:1.3.0, Greenwich mean time, March 28, 1964), severely crippled the highway system in the south-central part of the State. All the major highways and most secondary roads were impaired. Damage totaled more than $46...

Extensive geochemical anomalies are present along the west side of the Sheep Creek Range in Lander County, Nev. Anomalous concentrations of zinc, arsenic, mercury, silver, copper, lead, and to some extent gold, molybdenum, and antimony occur in iron-rich material along fracture planes and in quartz veins in Paleozoic formations. A...

Metallic sulfides, fluorite, barite, and celestite are widespread in the sedimentary rocks of the central United States. Many occurrences are epigenetic concentrations either in known major mineral districts or in clusters of deposits that warrant further exploration for potential ore. Evaluation of trace-element composition, of fluid inclusions, of depositional temperature, and of isotopic composition of sulfur may help discriminate potentially economic deposits from even more...

A northerly-trending group of quartz diorite stocks that cut Cretaceous, Eocene, 01igocene(?) and Pleistocene( ?) sedimentary rocks near Saindak, West Pakistan, contain oxidized disseminated copper minerals which may occur in commercial concentrations at depth. The stocks are enclosed by an aureole of albite-epidote hornfels about 4 miles wide that locally is cut by veins...

Water quality of streams tributary to Lakes Superior and Michigan was analyzed for 142 stations on 99 streams tributary to Lake Superior and 83 stations on 56 streams tributary to Lake Michigan during 1962-65. Concentrations of aluminum, copper, and iron were not affected greatly by flow or season. Magnesium, calcium,...