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During the early 1930's, more than 340,000 acres of abandoned farmland in New York State were purchased by the State Conservation Department for the planting, growing, and harvesting of trees. Since then, this land has developed from a heavy cover of weeds and brush into dense coniferous woodlands with trees averaging well over 30...

The Burro Mountain body is a crudely equidimensional block of unusually fresh ultramafic rock. This block, along with numerous smaller and more elongate serpentinite bodies, has been emplaced in a highly sheared Franciscan terrane immediately west of the Nacimiento fault. This fault separates two major structural units: (1) on the...

The basal complex of Puerto Rico consists principally of serpentinite, minor amounts of chert and spilite, and locally small blocks of amphibolite. A detailed structural and metamorphic study of a relatively large block of gneissic amphibolite at Las Palmas reveals that the rock has undergone repeated deformation and regional metamorphism prior to contact metamorphism by intrusive serpentinite. The first event...

Ground water of acceptable quality is commonly interspersed with water of inferior quality. Water of inferior quality may be naturally occurring salty water commonly underlying fresh water, or it may be enclaves of contaminated water from wastes that lie in the fresh-water bodies. Disposal of wastes on and in the...

No abstract available. ...

Counts on photographs and visual estimates of the numbers of territorial gulls are usually reliable indicators of the number of gull nests, but single visual estimates are not adequate to measure the number of nests in individual colonies. To properly interpret gull counts requires that several islands with known numbers...

Lymphocystis virus obtained from bluegills (Lepomis macrochirus) was cultured in the permanent bluegill cell line BF-2 and examined by electron microscopy in ultra-thin sections of cell cultures and in negative-contrast preparations from cells and from centrifuged culture medium. According to negative-contrast preparations, the icosahedral virions have an overall diameter close...

The possibility of using neutron activation analyses to differentiate sources of North American waterfowl was investigated by irradiating rectrices and wing bones of birds collected in several localities, and comparing the characteristic gamma-ray spectra. Canada goose (Branta canadensis) rectrices from Oregon specimens could be distinguished from those taken in Wisconsin...

Primary feather length, markings on the greater secondary coverts, and the degree of bill spotting were evaluated as characters for use in the spring to distinguish first-year, blue-winged teal (Anas discors) females from older ones. The length of the 10th primary feather did not prove suitable to separate different aged...

Whereas the previous Surveyor missions were undertaken to examine mare surfaces as potential landing areas for the Apollo Program, the primary objective of the Surveyor VII mission, based on purely scientific motivations, was to explore a contrasting highland region and, specifically, to determine the chemistry of the highland material for...

Ten amphibole specimens from a variety of metamorphic rocks such as talc schists, eclogites, and metamorphosed iron formations contain lamellae of a second amphibole oriented parallel to (1̅01) or (100), or both, of the host. Tremolites, actinolites, and hornblendes commonly have lamellae of a calcium-poor clinoamphibole with P21/m space-group...

Analysis of geologic data from 54 localities, mainly in the western United States, shows that concordant igneous masses intruded zones in nearly flat-lying sedimentary rocks where the thickness of cover was 3000 to 7500 feet. The depth of intrusion was apparently affected by a well-defined parting surface (bedding plane or unconformity), static load of the overburden...

The homonyn Navicula rotunda Andrews is replaced by the name N. rotundella Andrews; the homonym Epithemia irregularis Andrews is replaced by the name E. emarginata Andrews. The diatoms are from Trempealeau Valley, Wisconsin (Andrews, 1966)....

The forest of a small watershed-ecosystem was cut in order to determine the effects of removal of vegetation on nutrient cycles. Relative to undisturbed ecosystems, the cut ecosystem exhibited accelerated loss of nutrients: nitrogen lost during the first year after cutting was equivalent to the amount annually turned over in...

None of the expected stratigraphic and structural effects of a spreading sea floor have been imposed on the sedimentary fill of the Peru-Chile Trench. During at least the last several million years, and perhaps during much of the Cenozoic, the trench has not been affected by an oceanic crust thrusting...

Hydration of obsidian has been used to date rhyolite flows, containing obsidian or porphyritic glass, at Glass Mountain (Medicine Lake Highlands) and Mono Lake, California. The method is simple and rapid and can be used to date flows that erupted between 200 and approximately 200,000 years ago....

Diatremes in the Missouri River Breaks demonstrate systematic subsidence-ring structure, contain inclusions derived from far above and far below, and have been produced by gas-rich eruptions of alkalic ultramafic magmas. Similar magmas have produced diatremes in many localities in the world and are known to be closely associated with and...

Alkali amphiboles from Type III and Type IV metamorphic zones in blueschist facies rocks of Cazadero, California, and from comparable New Caledonian rocks have been characterized by X-ray crystallographic, optical, and chemical methods. The composition of any particular alkali amphibole is strongly controlled by the bulk composition of the host...

The artesian basin of the Dakotas has been studied for many years. The widely held concept has been that recharge enters the equivalents of the Dakota Sandstone, where they are exposed on the flanks of the Black Hills, and moves through this formation to the area of maximum development of the aquifer in eastern North Dakota and South Dakota. Some anomalies, difficult...

The purpose of this work is a theoretical consideration of equilibrium conditions in the system nepheline-alkali feldspar-plagioclase-alkali chloride aqueous solution based on the thermodynamic treatment of experimental data (Orville, 1963; Iiyama et al., 1963; Debron et al., 1961) for particular systems. The excess thermodynamic functions (ZE, SE, HE, VE) of solid solutions were calculated for it. These data...

Silicic volcanic rocks — dacite, rhyolite, and quartz porphyry — constitute about 35 percent of the Yavapai Supergroup, an older Precambrian sequence in central Arizona. In addition, the series contains about 30 percent pillow and amygdaloidal basalt, 5 percent andesitic rocks, and the remainder is mixed andesitic and silicic-bedded tuffaceous...

Geologic mapping, paleomagnetic stratigraphy, and potassium-argon dating were used to determine the time and volume relations of tholeiitic and alkalic basalt on Nunivak Island in the Bering Sea near the coast of Alaska. Volcanism on Nunivak Island occurred in distinct episodes separated by quiet intervals that lasted from 1.6 to...

The Southern Coulee is the southernmost and largest of the four Recent pumiceous rhyolitic coulees, or stubby flows, of the Mono Craters, eastern California. It is one of the youngest volcanic deposits of the Mono Craters and is largely bare and uneroded. The coulee is 3.6 km long and averages...

No abstract available....

An outstanding flood occurred in the Wapsinonoc Creek basin in east-central Iowa on June 7, 1967. The flood was the result of rainfall totaling from 4 to 13 inches in about 14 hours on the night of June 6 and the morning of June 7. The storm was nearly centered...