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In 1961 a 1000-foot drill hole near Harwich on Cape Cod, Massachusetts, penetrated 435 feet of Pleistocene deposits above 50 to 60 feet of crystalline limestone and phyllitic schist, and more than 500 feet of phyllitic schist with abundant quartz veins. Similar rock is known in the Pennsylvanian and Precambrian...

In the Balmat area in northern New York, tabular deposits of sulfide minerals parallel the layering in folded, siliceous magnesian marbles of a metamorphic complex commonly referred to as the Precambrian Granville Series. Sphalerite, pyrite, and, locally, pyrrhotite and galena have replaced the carbonate minerals in parts of the marble units. The contacts...

No abstract available....

No abstract available....

A statistical analysis is made of the sequences of annual tree ring widths and indices. The expected value of growth during any year is shown to be proportional to the standard deviation of the growth, so that the coefficient of variation is a measure of the sensitivity of the growth of a <span...

Precise measurements of fluctuations of ground-water temperature based on monthly readings in shallow glacial-outwash aquifers may be used to study ground-water movement and recharge. An increase in storage in the shallow basin of Okabena Lake, Worthington, Minnesota, permits the water to cover a much larger area and probably increases the opportunity for infiltration of...

A prominent aeromagnetic anomaly in Randolph County, Indiana, suggests the existence of a dikelike structure within the Precambrian basement rocks. Because of the ambiguity inherent in magnetic interpretation, a unique solution for the parameters involved (depth of burial, geometric configuration, and magnetic susceptibility of the mass producing the anomaly) is impossible. However, if one of the <span...

In 1958 the U.S. Geological Survey and the U.S. Weather Bureau jointly conducted a study of tritium fallout distribution over the continental United States, Alaska, and Puerto Rico. The observation period extended from early April to late July in most areas. While this was insufficient to cover the decay side of the...

A contour map of the Precambrian surface for a part of northeastern New Mexico has been prepared from aeromagnetic, gravity, and drill-hole data. The area extends approximately from the Colorado border south to latitude34° N., and from the foothills of the Sangre de Cristo Mountains east to longitude 104° W. Thirty-seven...

Some recent paleogeographic maps indicate that central Idaho was part of a major geosyncline throughout Paleozoic time. This concept, apparently based on thick marine accumulations far apart on the margins of the region, is inconsistent with field data. Within the area of the Idaho batholith, Permian(?) volcanic rocks rest either on batholithic rocks...

In a study of the relationship of magnetic anomalies to the magnetite content and structure of layered Precambrian iron-formations, the effective induced and remanent magnetizations of the Biwabik iron-formation were determined by analyses of aeromagnetic anomalies recorded 1,000 ft above the Biwabik in areas of known geology. The induced magnetization along the layers is relatively insignificant...

Measurements of erosion on miniature pediments in Badlands National Monument, South Dakota, show that during almost eight years, the pediments were lowered by sheetwash. The adjacent hillslopes have retreated leaving a belt of newly formed pediment from 6 to 12 cm wide at their bases. The hillslopes are rough and relatively permeable; the <span...

Landslide blocks of latest Oligocene or earliest Miocene age are preserved at several localities in northwestern South Dakota and southeastern Montana. These tilted blocks contain Late Cretaceous to late Oligocene rocks and are unconformably overlain by nearly horizontal strata of the Arikaree Formation of Miocene age. Undisturbed rocks of late Oligocene...

Electrical conductivity has been widely used in freshwater research but usual methods employed by limnologists for converting measurements to conductance at a given temperature have not given uniformly accurate results. The temperature coefficient used to adjust conductivity of natural waters to a given temperature varies depending on the kinds...

Glass electrodes suitable for measurement of divalent cations have been made and tested. Empirical and theoretical electrode equations have been presented to describe electrode behavior in a variety of aqueous solutions. Most electrodes show response interpretable as showing nearly ideal solid-solution behavior of the cations in the glass surface. The...

An understanding of water in relation to earth processes requires the collaboration of many disciplines....

The Carrizo Sand (Eocene), the basal unit of the Claiborne Group, can be recognized in the subsurface throughout much of southeastern Arkansas and is correlated with the Carrizo Sand of Louisiana and the Meridian Sand Member of the Tallahatta Formation of Mississippi. The term Carrizo Sand is appropriate for use in Arkansas, as the stratigraphic terminology...

Five areas of outcrop were examined along 120 miles of the coast of the Bellingshausen Sea east of the Thurston Peninsula. Hornblende quartz diorite is the principal rock in the area and occurs in a body of batholithic dimensions. The quartz diorite contains inclusions of older granulitic rock and is...

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No abstract available....

Well-developed lava tree molds were formed during the September 1961 eruption along the east rift zone of Kilauea Volcano. The upright molds were produced where fluid lava, flowing through dense tropical forest, became chilled against the larger trees and tree ferns and later drained away. Where the lava ponded temporarily...

Iron-nickel spherules, as much as 0.5 mm in diameter, have been found completely embedded in some philippinites. The spherules consist mainly of kamacite with unidentified pink inclusions. The meteoritic origin of these spherules seems reasonable, suggesting that the tektites containing them were formed by asteroidal or meteoritic impact....

No abstract available....

No abstract available....

No abstract available....