Search Results

Throughout most of northern Arizona the Redwall Limestone of Mississippian age is readily divisible into four lithologic units, designated in ascending order as the Whitmore Wash, Thunder Springs, Mooney Falls, and Horseshoe Mesa Members. The first and third members are thick-bedded to massive carbonate rock. The Horseshoe Mesa Member is...

The presence and relative abundance of bottom macrofauna in Lake Ontario are documented. Bottom samples were collected at 24 stations in September 1964. The quantity of organisms and the distribution of some species were affected by depth of water. Samples from the shallower stations (47.5 m or less) yielded an...

It has been known for a long time that the composition of the lanthanides in minerals is controlled to a large degree by crystallo-chemical factors, but is also greatly influenced by changes in geological environment. In general, igneous rocks rich in silica are favourable for the concentration of the heavy...

Ardennite, a rare silicate mineral, contains about 19 wt.% manganese. Some of the manganese atoms are in positions which are close enough to allow negative exchange and hence a reduction of the total magnetic susceptibility. It is shown that the susceptibility can be accounted for approximately by the treatment of...

The lower Thames and southeastern coastal river basins have a relatively abundant supply of water of generally good quality which is derived from streams entering the area and precipitation that has fallen on the area. Annual precipitation has ranged from about 32 inches to 65 inches and has averaged about...

No abstract available...

The Blackhawk Formation at Sunnyside, Utah, was deposited along the western margin of the Western Interior Cretaceous sea during southeastward withdrawal of the sea. Sand was the dominant type of land-derived sediment deposited in the Sunnyside district during the regressive phases. Sand bodies prograded seaward in response to changing sediment...

The meteorite classes of Prior and Mason are assigned to three proposed genetic groups on the basis of a combination of compositional, mineralogical, and elemental characteristics: l) the calcium-poor, volatile-rich carbonaceous chondrites and achondrites; 2) the calcium-poor, volatile-poor chondrites (enstatite, bronzite, hypersthene, and pigeonite), achondrites (enstatite, hypersthene, and pigeonite), stonyirons...

The electron probe X-ray microanalyzer has been used to determine the compositional variability of the groundmass minerals and glass in 10 specimens from a complete 225-foot section of the prehistoric tholeiitic lava lake of Makaopuhi Crater, Hawaii. The order of beginning of crystallization was: (1) chromite, (2) olivine, (3) augite,...

The name black calcite has been applied from time to time to a dark gray to black variety of calcite or aragonite in metalliferous ore deposits in the Western States. Most of the material shows curved, roughly rhombic cleavage. The color is due to dispersed minute grains of one or...

The Shetucket River basin has a relatively abundant supply of water of generally good quality which is derived from precipitation that has fallen on the basin. Annual precipitation has ranged from about 30 inches to 75 inches and has averaged about 45 inches over a 35-year period. Approximately 20 inches...

The last Tuesday in August, between five-thirty and seven in the evening, we zigzaged through this glorious jungle, attended by a family of Wood Pewees for whom we seemed to be stirring up a feast of flying insects. There was gentle background music by Mole Crickets....

Analyses by atomic absorption for detrital gold in more than 2,000 beach, offshore, marine-terrace, and alluvial sands from southern Oregon have shown that the values determined from raw or unconcentrated sediment containing small amounts of gold are neither reproducible nor representative of the initial sample. This difficulty results from a...

In the Greenville quadrangle, west-central Maine, slate, siltstone, and sandstone (calcareous and noncalcareous) of probable Silurian to Early Devonian age are intruded by a large mafic pluton and two granitic stocks of probable Early Devonian age. Ages of the sedimentary rocks are based upon tentative correlations with fossiliferous beds in...

Rare-earth contents of 20 allanites and 13 monazites, accessory minerals from a restricted outcrop area of intrusive granitic rocks, are reported. A quantity called sigma (Σ), which is the sum of the atomic percentages of La, Ce and Pr, is used...

A number of iron meteorites contain elongated inclusions consisting predominantly of troilite, which have been termed Reichenbach lamellae. Two types of inclusions exist, the first up to 6 cm long and 0·2 mm wide, the second up to 2 cm long and 3 mm wide. The first type contains troilite...

Up to 1700 feet of the upper Miocene-lower Pliocene Yakima Basalt of the Columbia River Group underlie much of the eastern flank of the Cascade Range in the Tieton River area, Yakima County, Washington. Local prebasalt relief was more than 1700 feet, so thicknesses of each of the 15...

Northern and central Johnson County, Wyo., is an area of about 2,600 square miles that lies principally in the western part of the Powder River structural basin but also includes the east flank of the Bighorn Mountains. Sedimentary rocks exposed range in age from Cambrian to Recent and have an...

Dawsonite NaAl(OH)2C03 is a rare mineral that occurs in relative abundance over hundreds of square miles in the Piceance Creek Basin of northwestern Colorado, as a rock-forming constituent of the oil shales in the green River Formation. In some specimens it makes up 25 percent by weight of the shale....

The east-trending east rift zone of Kilauea volcano on the island of Hawaii is 50 km long and up to 3 km wide. It consists of three elements arranged roughly in three belts from north to south: 1) eruptive fissures, cracks, faults, and narrow grabens, 2) cinder cones (produced by...

The chemical composition, both major and minor constituents, of 60 samples of phosphorite from the Phosphoria Formation was determined. Major constituents of the average phosphorite are, by weight per cent: SiO2, 11·9; Al2O3, 1·7; Fe2O3,1·1; MgO, 0·3; CaO, 44·0; Na2O, 0·6; K2O, 0·5; total H2O, 2·2; H2O−, 0·6; TiO2, 0·1;...

Rare earths are but trace constituents of marine apatite. However, as millions of tones of such apatite are dissolved annually to make phosphoric acid, an opportunity exists for greatly increasing RE output as by-product of fertilizer production. New, complete, quantitative analysis of RE in representative apatite concentrates reveal that the...

The rapid increase in the stocks of gizzard shad in Lake Erie since 1950 unquestionably had an important effect on the ecology of the lake. The present study, based on almost 24,000 fish collected by various means in 1952-55 in or near the island area of western Lake Erie was...