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Humic acids, the most abundant organic components of natural water systems, are complex mixtures of molecular aggregates of different chemical and physical properties. The first step in the study of such a mixture is the fractionation of the mixture. The most common approach with humic acids is to attempt to obtain a molecular weight fractionation...

A thick sequence of highly deformed flyschlike metasandstone, slate, and argillite crops out in southern Alaska in the Kenai-Chugach Mountains and on Kodiak and the Shumagin Islands to the southwest. These poorly fossiliferous rocks have long been considered Cretaceous in age because of scattered occurrences of fragmentary shells of Inoceramus. Mainly on the basis of...

Many housing projects in the metropolitan area of Boston are beyond the reach of municipal sewer systems. Waste water disposed of through septic-tank or cesspool systems percolates to ground-water reservoirs and eventually reaches the streams. The dissolved-solids load in the streams receiving septic-tank effluent is increased by an amount that can be predicted from the...

The southern complex, south of the Marquette synclinorium in the Marquette district of Michigan, is dominantly granitic.  The granitic parts of the complex have Rb-Sr ages of about 2.5 b.y. and are classed as of Precambrian W age. The rocks are divided into two major units: (1.) Bell Creek Gneiss consisting mostly of...

Recently completed fission-track and K-Ar dating of zircon, sphene, apatite, muscovite, biotite, and hornblende indicate that the Clayton Peak stock was intruded 37-41 m.y. ago, the Alta stock about 32-33 m.y. ago, and the Little Cottonwood stock between 24 and 31 m.y. ago. Pb-a ages on zircon, though showing the same sequence, are about twice...

The variation in solvent composition of a mixed solvent used in Soxhlet extraction of sediments has apparently often been overlooked. Owing to azeotropic distillation of the solvent introduced into the apparatus, care must be taken to determine the composition of the solvent actually doing the extracting....

The specific yield of the alluvial aquifer in the Gila River flood plain in southeastern Arizona has been determined using two methods of analysis - the time-drawdown method and the soil-moisture-content method. Time-drawdown data measured at 17 observation wells during a 3.5-day aquifer test define an average apparent specific yield of 0.13. Soil-moisture-content data...

New magnetization data for Late Cretaceous glassy welded tuffs, volcanic breccias, and altered basalts from the Elkhorn Mountains volcanic field, together with geologic, mineralogic, and K-Ar data, indicate that (1) the glassy tuffs have unusually strong, uniform remanent magnetizations which are reversely polarized, much of the remanence perhaps residing in submicroscopic single-domain iron oxide particles within...

Lithostrotion reiseri n. sp. is a cerioid, colonial coral, index fossil for microfossil zones 12-13 (Meramec) in the Lisburne Group in the central and eastern Brooks Range, arctic Alaska....

The occurrence of the second known specimen of Parahyus vagus, from the Tepee Trail Formation, Wyoming, is recorded. As the first specimen was reported from the lower Eocene, this second occurrence casts doubt on the supposed age ranges of both Parahyus and the Tepee Trail....

Roll-type uranium deposits contain both ore-stage pyrite and preore or diagenetic pyrite that was present in the host rock before the deposits began to form. Ore-stage pyrite forms as the result of redistribution and accretion from the preore pyrite. Accretion of the ore-stage pyrite seems to be governed by natural laws that limit its concentration...

Phyllite and marble dredged from the lower part of the continental slope between Cuba and the Yucatan Peninsula seem to support the contention that a pre-early Tertiary metamorphic belt extends from the western Greater Antilles into northern Central America. The minimum K-Ar ages derived from the samples suggest that the metamorphic event was pre-Late Cretaceous,...

A photograph made with a level camera, if taken at a known height above a permanent mark on the ground, can be later repeated with exactness for measurement of changes in terrain. Such a photograph is one of several means for establishing a geologic bench mark and is especially useful for monitoring the subtle...

A classification of wetland plant communities was developed for a study area in north-central Minnesota in order to analyze data on waterfowl use of habitat that were gathered by radio telemetry. The classification employs features of several earlier classifications in addition to new classes for bogs and lakeshore communities. Brief...

Abstract not submitted to date...

Potential commercial fish production was estimated for U.S. waters of western Lake Erie in 1969 from pounds landed and pounds discarded. Periodic observations of catches in haul seines and trap nets revealed that about 37% of the catch (by weight) in haul seines and 26% of that in trap nets...

The acid-insoluble impurities of small samples of minerals are determined by a microgravimetric procedure. A Schwarz von Bergkampf glass filter stick with paper filter medium is used to separate the insoluble material. The filtration apparatus and procedural details are described....

Scolecobasidium humicola, a previously undescribed fungal pathogen of fish was isolated from coho salmon (Oncorhynchus kisutch). In natural infections the kidney was the organ most affected. The disease was difficult to transmit experimentally and appeared to be only weakly contagious....

During the years 1954-70, 230 pintails (Anas acuta) banded in North America were reported from eastern Asia, primarily Siberia. Most of the birds were shot on the breeding grounds in May. The movement into eastern Asia of pintails banded in the interior of North America was directly correlated with the...

It is generally assumed that wild, North American female dabbling ducks (Anatinae: Anatini) select new mates each year and may return to the same nesting areas in consecutive years (McKinney 1964, Wildfowl 16: 93). Lincoln (1934, Bird-Banding 5: 151) first documented migrational homing in a female Mallard (Anas platyrhynchos), and...

Ecological blunders of man, such as timber exploitation, draining of wetlands, construction of canals and dams, and pollution have been mainly responsible for serious environmental degradation and catastrophic losses of fish and wildlife values in the Great Lakes Basin. Consequently, the major emphasis of the Bureau of Sport Fisheries and...

Fishery productivity of the Great Lakes has declined drastically since settlement of the area. Premium quality fishes of the Great Lakes such as whitefish, lake trout, and walleyes have been replaced by less desired species. This change is attributed to selective overfishing, pollution, and the extreme instability of fish populations....

Selenium was determined in duplicate portions from three bottles of six U.S.G.S. standard rocks by a spect rofluorimetric procedure. The following averages, as p.p.m. Se, were obtained: PCC-1, 0.031; GSP-1, 0.088; BCR-1, 0.12; SCo-1, 0.91; MAG-1, 1.3; and SGR-1, 3.7. One-way analysis...

No abstract available....

The point of zero charge of forsterite shifts from an estimated 8.9 for the unaltered mineral to 8.4 and 8.0, respectively, after being weathered artificially for 1 h and 4 h. These results corroborate the presence of magnesium-deficient surfaces on the weathered...