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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....

No abstract available. ...

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...

When high pressure (250 to 300 kilobars) was applied suddenly (shock-loading) to gabbro, the plagioclase was transformed to a noncrystalline phase (maskelynite) by...

Infectious pancreatic necrosis virus (IPN) of salmonid fishes has been isolated and identified in suspect but normal-appearing stocks of adult brook trout (Salvelinus fontinalis), and thus a pattern for the epizootiology of the virus has been demonstrated. Virus titers as high as 106.5 ID50 were found in egg fluids from 7 of...

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...

The influence of individual factors such as geologic and hydrologic characteristics of environment, biologic activity in soil, and pollutants on ground‐water composition is discussed. Aspects of chemical equilibria in ground water, sorption reactions, carbonate equilibria, chemistry of iron, and factors altering equilibria are presented....

No abstract available....

No abstract available....

No abstract available....

The old surface that extends over a long north-striking belt in northern Chile probably reached the mature stage of erosion by middle Tertiary time. Low areas are mantled by the piedmont deposits of the pampa, and the higher parts exhibit rock decay, oxidation, leaching, and super-gene enrichment of sulfide mineral deposits as a...

No abstract available. ...

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...

Volcanic rocks dredged from seamounts, fault ridges, and other major geological features of the northeast Pacific Ocean include a wide variety of basalts. Most of these are vesicular, porphyritic types with near analogues in the Hawaiian and other oceanic islands. in addition, aluminous basalts and diabasic tholeiites impoverished in potassium...

The abundance of radiogenic Sr87 relative to Sr86 at the time of crystallization has been determined for 45 rocks. The total range in the ratio Sr87/Sr86 is less than 2 percent. Ratios for recent lavas range from 0.702 to 0.711. Oceanic basalts are closely grouped at 0.703, whereas ratios for continental volcanic rocks...

Sediments cored to a depth of about 1 m in Bay St. George, Newfoundland, were examined for grain‐size distribution and minerals. The sediments are light brown silty clays, the principal minerals of which are chlorite and muscovite mica. The scarce sand consists of fresh detrital grains of blue‐green amphibole, biotite, epidote,...

No abstract available....

No abstract available....

When high pressure (250 to 300 kilobars) was applied suddenly (shock-loading) to gabbro, the plagioclase was transformed to a noncrystalline phase (maskelynite) by a solid-state reaction at a low temperature, while the proxene remained crystalline. The shock-loaded gabbro resembles meteorites of the shergottite class; this suggests that the latter formed...