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The name Beaverhead formation is proposed for a thick sequence of conglomerate, sandstone, siltstone, and limestone that crops out over an area of at least 400 square miles in Beaverhead County, Montana, extends southward across the Montana-Idaho boundary, and may extend eastward into Madison County. These rocks are clearly sedimentary...

A detailed study of the west-central part of the Gunnison Plateau, Utah, has disclosed stratigraphic and structural relations important in the geological history of central Utah. The area mapped includes the eastern half of the Axtell No. 2 quadrangle, Manti area (U. S. Dept. of Agriculture, Soil Conservation Service).The bedrock...

Wall-like ridges of limestone that stand well above the surrounding terrain are an interesting phenomenon on the island of Okinawa. These ridges rim a variety of topographic features, but all are believed to represent the same formative processes. Rimming ridges or walls occur along the banks of streams crossing areas...

Various origins have been proposed for the itabirite and associated hematite ores of Minas Gerais, Brazil. The U.S. Geological Survey, in cooperation with the Brazilian Departamento Nacional da Produqao Mineral, has undertaken a comprehensive program of mapping of these Precambrian deposits, which bear many similarities to other Precambrian iron formations....

No abstract available. ...

The author has developed equations and approximate curves to express the percentage of the total sediment discharge that is carried in suspension above the lowest point reached by the nozzle of a depth‐integrating sediment sampler. He assumes that bed load and suspended load are defined by the equations in a...

The U.S. Geological Survey has recently measured and sampled the Phosphoria formation at many localities in Idaho and other western states. These data will not be fully synthesized and analyzed for several years, but segments of the data, accompanied by little or no interpretation, are published as preliminary reports as...

No abstract available....

The phosphate deposit in Uruguay described here is of interest primarily because it is believed to be a superficial deposit that resulted from the action of guano on volcanic rock. Even though some of the rock contains as much as 30 per cent P206, it is unavailable as a source...

Quartz pods and quartz veins devoid of economic minerals occur in the cobalt-copper mineralized Blackbird mining district in Lemhi County, Idaho. These barren quartz bodies are found in regionally and thermally metamorphosed rocks of the Yellowjacket formation (Belt series) of Pre-cambrian age and are believed to be derived from the enclosing quartz-biotite and quartz-biotite-garnet-chloritoid schists by metamorphic differentiation. Other rocks that possibly are...

Small bodies of granophyre occur in the upper part of diabase bodies of Triassic age in southeastern Pennsylvania. One near Harrisburg was penetrated by a diamond-drill. Drill core specimens show a gradation from diabase to granophyre.New data include 10 chemical analyses, spectrographic determinations of trace elements, and the results of...

The steep and rugged mountains of Southern California contain considerable ground‐water storage. A large portion of the runoff is seepage from this storage The variations in runoff distribution depend on the geology, physiography, and soil cover of these mountain areas....

Estimates of the weights of pyroclastic material and lava erupted by Parícutin Volcano from early 1943 to early 1952 have given a pyroclastic weight of some 2230 million metric tons and a lava weight of about 1330 million metric tons, making a total of 3560 million metric tons of solids....

No abstract available....

No abstract available. ...

As part of a comprehensive investigation of the phosphate deposits of the western field begun in 1947, the U.S. Geological Survey has measured and sampled the full thickness of the Permian Phosphoria formation and its partial correlative, the Park City formation, at many localities in Utah and other states....

No abstract available....

No abstract available. ...

A terminology is suggested to aid the field geologist in describing the structures of stratified and cross-stratified rock units. Qualitative terms describing the character of rock layering are stratification, stratum, cross-stratification, cross-stratum, set, coset, and composite set. Quantitative terms applying to the thickness of stratification are very thick-bedded, thick-bedded, thin-bedded, very thin-bedded, laminated, and thinly laminated. Quantitative terms...

The Dolores bench is about 2 miles northwest of Uravan, Montrose County, Colo. From 1913 to November 1952 about 95,000 short tons of ore averaging 0.40 percent U3O8 and 2.0 percent V2O5 was mined from the Dolores bench. The production represents three periods of activity--1913-18, 1938-43, and 1948-52. The ore deposits...

The U.S. Geological Survey has measured and sampled the Phosphoria formation of Permian age at many localities in Wyoming and adjacent states. These data will not be fully synthesized for many years, but segments of the data, accompanied by little or no interpretation, are published as preliminary reports as...

The U.S. Geological Survey has recently measured and sampled the Phosphoria formation at many localities in Wyoming and adjacent states. These data will not be fully synthesized for many years, but segments of the data, accompanied by little or no interpretation, are published as preliminary reports as they are...

As part of a comprehensive investigation of the phosphate deposits of the western field begun in 1947, the U.S. Geological Survey has measured and sampled the Phosphoria formation of Permian age at many localities in Wyoming and adjacent states. These data will not be fully synthesized for many years, but...

The U.S. Geological Survey has recently measured and sampled the Phosphoria formation at many localities in Montana and other western states. These data will not be fully synthesized and analyzed for several years, but segments of the data, accompanied by little or no interpretation, are published as preliminary reports as...