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Pre-Tertiary rocks of the Blue Mountain region of central and northeastern Oregon comprise three major sedimentary and volcanic sequences and two distinct intrusive magma series. The ages of the sedimentary-volcanic sequences are Paleozoic, Late Triassic-Late Jurassic, and middle Cretaceous (Albian to Cenomanian), respectively. The earlier intrusive magma series ranges in composition from peridotite to albite granite and was emplaced during the major...

Profiles of the basement surface in western Kansas and Nebraska were constructed by drawing smooth curves through the shallowest depths estimated from aeromagnetic anomalies along six widely spaced traverses. Ratios of inferred-depth-to-basement to true depth along the traverses ranges from 0.7 to 1.0. Clusters of shallow depth estimates commonly yield an average estimate within 15 percent of the true depth....

THIS note reports measurements made in an attempt to determine: (1) the possible effect of xenoliths on whole-rock basalt age determinations; (2) whether or not potassium-argon age determinations on xenoliths in basalt might approximate the age of the basalt flow. The field location is in the...

THROUGH a fortunate circumstance, a recording magnetometer was operating in the city of Kodiak, 30 km north-west of the surface trace of a fault zone along which movement occurred at the time when the earthquake occurred in Alaska on March 27, 1964. Fortunately, too, the instrument...

Characteristic minerals are psilomelane, hollandite, cryptomelane, and coronadite, more rarely ramsdellite and pyrolusite. Host rocks are Mn-deficient; 80 percent of examples are middle to late Tertiary layered volcanics. Though deposits are shallow, mostly mined to only 100-200 feet (maximum 500 feet), a hypogene origin is...

The ratio of cation to hydrogen-ion concentration is used as a basis for coordinating many observed varieties of silicate rock alteration. Low ratios drive alteration from feldspar through sericite, montmorillonite, or paragonite, toward kaolinite or pyrophyllite. Principal controls of ratio are reactions with wall rock,...

Deposits of ferruginous nickeliferous lateritic soils formed by weathering in place of ultramafic rocks occur at several places in northwestern California and southwestern Oregon, mostly in the Klamath Mountains province. Most of the deposits have been derived from relatively fresh peridotite, although at least one...

A well drilled for geothermal power near Salton Sea in Imperial Valley, Calif., is 5,232 feet deep; it is the deepest well in the world (1962) in a high-temperature hot spring area. In the lower half of the hole temperatures are too high to measure with available equipment, but are...

Right-lateral separation of about 120 miles along Chatham Strait Fault is suggested by apparent displacement of major geologic features on opposite sides of the fault....

Strongly oriented lineaments, defined by lake shores and stream and vegetation alignments, are distributed throughout more than 45,000 square miles of the Beni basin in northeastern Bolivia. The area in which these features occur is a flat, poorly drained, lake-studded plain. It is underlain by flat-lying, poorly consolidated, continental clastic...

Potassium-argon dates of 90,000 ± 90,000 years and 60,000 ± 50,000 years on the basalt in Sawmill Canyon of the Sierra Nevada, California, that underlies a moraine correlated with the Tahoe Glaciation and overlies pre-Tahoe till show that the Tahoe is probably less than 100,000...

The movement of 47 barchan dunes on the west side of Salton Sea, California, ranged from 325 to 925 feet over the 7 years between 1956 and 1963, an average of 82 feet per year. During the 15 years between 1941 and 1956, the movement...

Colored plastic adhesive tape wrapped around the tarsus has been used successfully for color-marking birds and has proved to be easy to put on, adaptable, permanent, and colorfast....

No abstract available....

Geologic interest in Thorne Cave stems from its link with valley alluvium along Cliff Creek, which accumulated to a height of 48 ft., continued to build up another 13 ft. while men lived here, and then reached 30 ft. higher-sealing in the signs of man. Mineralogic study shows that ground water then circulated...

No abstract available....

No abstract available....

The Central Kentucky mineral district occupies the greater part of the Blue Grass lowland of Kentucky, which lies astride the Lexington dome and the Cincinnati arch. The oldest exposed rocks of the mineralized area are limestones of Middle Ordovician age. The paragenesis throughout the district is constant and traceable, although the relative abundance of minerals varies from vein to vein....

This discussion of the lithology and microfauna of the clastic facies of the Ecocene and Paleocene rocks of Florida is based mainly on data obtained from the study of many cores taken in the Oil City corporation Walton Land and Timber Co. well 1, Walton County, Fla. Although the fauna...

Age of woodcock (Philohela minor) can be accurately determined throughout the year by differences in pattern, color, and wear of secondary feathers. Immature woodcock retain most secondaries during the postjuvenal molt that begins in July or August and ends in October. In contrast, subadults (first-year adults) and older woodcock molt...

The genus Composita consists of smooth-shelled athyroid brachiopods which in North America have a range from Late Devonian or Early Mississippian to Permian. Morphologic variation in the genus has been recognized by earlier workers, but few have tried to show exact relationships among the various forms. The present writers have...

Livetrapping of opossums at the Patuxent Research Refuge in Maryland over an 8-year period resulted in the capture of 224 opossums, with 541 trap records. The maximum recorded trap life was 29 months, and the greatest estimated age was 36 months. Opossums did not enter traps readily, and the average...

The radioelement content of the major part of the southeast Texas Coastal Plain sedimentary sequence falls within a range common for sandstones and shales. Exceptions to the normal limit are mainly in small, widely scattered areas. One anomalous area, however, covers several tens of square miles and contains most of the important uranium deposits. Both mechanical and chemical dispersion of radioelements takes...

The radioelement content of the major part of the southeast Texas Coastal Plain sedimentary sequence falls within a range common for sandstones and shales. Exceptions to the normal limit are mainly in small, widely scattered areas. One anomalous area, however, covers several tens of square miles and contains most of the important uranium deposits. Both mechanical and chemical dispersion of radioelements takes...

No abstract available. ...