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The gold pan is ordinarily regarded as a tool for sampling placer deposits. Another and very important application is shown to be the sampling and study of decomposed bedrock, in regions where outcrops of hardrock are scarce or lacking. This technique was proposed and used by Derby, an American geologist...

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A drafting instrument which provides a ruling edge for drawing arcs of circles the radii of which are unusually long is described. A complete range of arcs of different curvature, within the limits prescribed by the construction of the instrument, are obtainable. This instrument was developed originally to allow accurate construction of circular arcs of very low...

Total‐intensity aeromagnetic surveys of the Aleutian Marshall, and Bermuda Islands were completed in 1948. The anomalies associated with the Aleutian volcanoes are attributed mainly to topographic relief and are not an indication of the degree of volcanic activity. Eniwetok presents a magnetic pattern that would be produced by an irregular‐shaped rimmed depression in the basement, modified by the two adjoining seamounts, and differs from...

No abstract available....

An epizoological study of Plasmodium infections in wild birds of Kern County, California, in the years 1946 through 1951 greatly extended knowledge of the occurrence of these parasites and their behavior in nature. Examination of 10,459 blood smears from 8,674 birds representing 73 species resulted in the observation of Plasmodium...

Abasic Question that must be answered for any archaeological site is, how old is it? Although some archaeological sites can be dated on the basis of archaeological correlations alone and although dendrochronological (Giddings, 1952, pp. 105-110) and radiocarbon methods give absolute ages for other sites, many sites can be dated only by methods based on the geologists' knowledge of geographic and...

This investigation was made to determine the surface and subsurface geological conditions along the proposed relocation of Route 138 in the vicinity of the Torrey Street crossing in Brockton, Mass. The field work was done in April 1952 as part of cooperative program of the Commonwealth of Massachusetts, Department of...

No abstract available....

The Copper Cities copper deposit in the Globe-Miami district, Arizona, is now in process of development. It is of the "porphyry" type and occurs in a body of quartz monzonite that has been intruded by smaller masses of granite porphyry. The hypogene sulfides are pyrite, chalcopyrite, and a very little molybdenite. Pyritic mineralization extends over a large area...

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No abstract available....

The sedimentary iron-formations of Precambrian age in the Lake Superior region can be divided on the basis of the dominant original iron mineral into four principal facies: sulfide, carbonate, oxide, and silicate. As chemical sediments, these rocks reflect certain aspects of the chemistry of the depositional environments. The major control, at least for the sulfide,...

A field excursion following the route described herein was conducted as a part of the curriculum of the 6th Ground Water Short Course, which was held by the Geological Survey at the University of Arizona in April 1954. The route log and descriptive text were designed to provide a general...

One of the very obvious geologic phenomena that is continuously in operation throughout the Earth's land surface is erosion, the process of wearing away the soil or the surface mantle. The falling of rain drops on an unprotected slope, the flow of water across land or in a channel, the borings of a rodent, the...

A new Pennsylvanian cone genus (Litostrobus iowensis, n. gen., n. sp.), apparently of sphenophyllalean affinity, is described on the basis of a coal-ball specimen from the Urbandale Mine, Urbandale, Iowa. The cone is small and extremely simple in organization. It consists of superposed whorls of twelve bracts each. The bases of the bracts are fused to form shallow cuplike...

In 1953 the Chattanooga shale in the Sequatchie anticline was tested for its uranium content by seven diamond drill cores. Concurrent with the drilling, geologic field work was done to determine the distribution, thickness, and structural setting of the shale. The results of this investigation indicate that the Chattanooga...

A 22-square mile tract (McKinley Mountain Area) of pre-Cambrian rocks and veins containing thorium was mapped at the scale of 1:6,000. This tract lies on the west flank of the Wet Mountains, Custer and Fremont Counties, northeast of Westcliffe, Colo. The bedrock is a complexly interlayered sequence of gneisses of metasedimetary...

The U.S. Geological Survey has made estimates of the reserves of uranium and vanadium in the carnotite deposits explored by Geological Survey drilling on the Colorado Plateau. This report presents an appraisal of the accuracy of the reserve estimates for deposits in the Uravan mineral belt, the causes of inaccuracy,...

The copper and uranium-vanadium deposits of the Coyote district, Mora County, N. Mec, are confined to the lower 2,000 feet of the Sangre de Gristo formation of Pennsylvanian and Permian age. A narrow belt of deposits in steeply dipping or overturned rocks extends for 7 miles along Coyote Creek south...

This report is a survey of present and potential production of monazite from part of the Maryland-Florida section of the Atlantic Coastal Plain. The part of the Coastal Plain covered here is the outer (shore-ward) half. In this area, all the large heavy-mineral placers so far discovered occur in sand bodies...