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A continuous strip of geologic maps has recently been completed along the Idaho-Montana state line between Clark Fork, Idaho, and Superior, Montana. New stratigraphic and petrographic information provides the basis for stratigraphic correlations and for the interpretation of facies changes in this part of the basin of deposition of the Precambrian Belt <span...

Bouguer gravity values at about 11,000 stations in east-central California range from -14 mgal near Merced to -274 mgal in Long Valley. Gravity lows in the west and south parts of the San Joaquin Valley and over local basins south and east of the Sierra Nevada are produced by large thicknesses of Upper Cretaceous and Cenozoic...

Kirchner Marsh and Lake Carlson are located 3 miles apart in Dakota County about 15 miles south of Minneapolis in the St. Croix moraine, which was formed by the Superior lobe during the Gary phase of the Wisconsin glaciation. During the Mankato phase that followed, the Des Moines lobe advanced to within...

Measurement of more than 1200 cross-beds in lower Pennsylvanian sandstones of the southern Appalachian Mountains reveals a broad pattern of sediment transport to the southwest and west. Most of the sand appears to have been derived from the east and to have moved south-westward parallel to the axis of the Appalachian geosyncline. The pattern...

A metasomatic origin seems established for large parts of the granite phacoliths in the northwest Adirondack Mountains, New York. This conclusion is based upon the discovery and detailed mapping of a blurred but widespread stratigraphic sequence in the phacoliths. Highly complicated patterns of relict beds are defined by alternations of granitic gneiss, amphibolite, oligoclase-quartz...

Natural gamma-radioactivity patterns in Washington County, Maryland, reflect the principal variations in lithology. The highest radioactivity is associated with the more argillaceous parts of the geologic section and with soils derived from high-potassium carbonate rocks. Surface radiation intensity ranges from about 5 to 30 microroentgens per hour, of which the rocks contribute...

Ostracods and Foraminifera, associated with mollusks, indicate a marine depositional environment for part of the Bootlegger Cove Clay. The definite Arctic and North Atlantic affinities of the microfauna suggest a possible migration through the Bering-Chukchi seaway during the late Pleistocene....

Extensive deposits of kaolinite in Florida are formed by transformation of montmorillonite during low-temperature supergene weathering. The transformation occurs by intracrystalline leaching of interlayer cations and tetrahedral silica layers. Interposition of stripped layers within montmorillonite creates a regular 1:1 mixed-layered montmorillonite-kaolinite, a new clay structure. Kaolin-like layers are nourished by...

he Reef Creek fault is in northwestern Wyoming, a few miles east of the northeast border of Yellowstone National Park. It lies within the area covered by the more extensive Heart Mountain fault. Like that fault, it is a décollement or detachment fault in which strata became detached along a basal shearing...

There is a vital need for hydrologic data representing various environments that are free from the effects of man's activities. Without such data hydrologists will be stymied in distinguishing hydrologic changes caused by man from those caused by climate. To provide this background information, the U. S. Geological Survey is planning a nationwide hydrologic <span...

Vast quantities of saline ground water await new commercial uses and economical demineralization processes for recognition as a valuable resource. Saline ground water is more widely distributed than any other natural resource, occurring throughout the United States and in geologic formations ranging from the oldest to the youngest. The Coastal Plain has the...

Gibson Peak pluton is the most discordant of several dominantly granitic intrusions in the Trinity Alps of northern California. It formed during Nevadan (Late Jurassic) deformation by emplacement of at least five discrete rock units that define a successively more silicic series, ranging from hypersthene gabbro to trondhjemitic tonalite. Contact features suggest that several...

A composite dike of probable Tertiary age intrudes Precambrian granodiorite 6 miles north of Klondyke, Arizona. The dike is exposed discontinuously for about 1500 feet along the strike and has a core of porphyritic rhyolite 15-20 feet thick flanked by coarsely porphyritic andesite 1-2 feet thick. Field evidence indicates that the rhyolite is later than...

No abstract available....

The disodium salt of 3,6-endoxohexahydrophthalic acid (disodium endothal) and the derivative identified by the manufacturer as the di-N,N′-dimethylococoamine salt of endothal (coded as TD-47) were particularly effective upon submersed species of aquatic vegetation as contact herbicides. Disodium endothal at concentrations of 0.5 to 10.0 ppmw was effective in controlling...

Using Rittman's classification to determine the clan, we suggest the following abundance figures: basalts (99), 38 p.p.m. Sc; andesites (72), 34 p.p.m. Sc; dacites (68), 21 p.p.m. Sc; rhyodacites (32), 14 p.p.m. Sc; quartz latites (14), 11 p.p.m; rhyolites (24), 5 p.p.m. The scandium was determined spectrographically on samples for...

No abstract available....

No abstract available....

A method has been developed for the extraction and chemical microanalysis of individual fluid inclusions, or groups of inclusions, in the milligram range. Usable quantitative analyses for Na, K, Ca, Mg, CI, B, and SO* have been obtained of mineral samples containing several milligrams of inclusion fluid, and with increased experimental errors,...

Much of the disagreement over "epigenetic" And "Syngenetic" Deposits Is Semantic; Some Ores And altered rocks are in part syngenetic and in part epigenetic and for them the term "diplogenetic" is proposed. All these terms are primarily time terms related to the contemporaneity of the deposit and the enclosing rock, but...

Microgram quantities of copper, manganese, and zinc, corresponding to concentrations greater than 100 parts per million, were found in milligram quantities of primary inclusion fluid extracted from samples of quartz and fluorite from two types of ore deposits. The results indicate that neutron activation is a useful analytical method for...

Glauconite from the upper part of the Missoula Group of the Belt Series, Flathead County, Montana, has been dated at 1070 million years by potassium-argon and rubidium-strontium analyses. This is the first glauconite of Precambrian age reported in North America....

A skeletal fuzz that consists mostly of open space probably covers the moon to a depth of several millimeters or centimeters. The solid part of the fuzz probably consists of randomly oriented linear units, with or without enlarged nodes, which either anastomose in a mesh or are branching....

Nestling mourning doves (Zenaidura macroura) were banded and checked for band loss prior to fledging at Parchman, Mississippi, during the months of June-August, 1960. Three hundred seventy-seven nestlings 4-6 days of age were banded, 117 with size 3 bands, 120 with size 3A bands, and 140 with size 3A bands...

Adult females in a cottontail (Sylvilagus floridanus) population produced seven or eight litters during the 1961 breeding season. A synchrony of the conception dates was maintained throughout the breeding season. Data about ovulation rate, prenatal mortality, and litter size for each litter are presented. The first litter was smallest, averaging...