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The U. S. Geological Survey is beginning a major new program to create a nationwide digital cartographic data base from 1:100,000-scale maps by the end of the decade. This data base will supplement the currently available 1:2,000,000-scale national data base and the selected coverage at 1:24,000-scale. It is anticipated that...

Alunite deposits formed 23 m.y. ago in near-surface, highly oxidizing conditions at the tops of hydrothermal plumes that were spaced at 3- to 4-km intervals around a monzonite stock. The delta 34 S values of 11.5 to 15.4 per mil for replacement alunite along with geologic constraints indicate that sulfate sulfur was...

The U. S. Geological Survey operates two water-quality laboratories. The quality of data produced by each laboratory is judged primarily from an evaluation of the data obtained from the analysis of reference samples. Quality-assurance reports that contain an analysis of the results obtained from chemical analysis of these reference materials...

Probabilistic methodology used by the U.S. Geological Survey is described for estimating the quantity of undiscovered recoverable conventional resources of oil and gas in the United States. A judgmental probability distribution of the "quantity of resource" and its properties is determined for a geologic province or basin. From this distribution,...

No abstract available....

No abstract available....

Proterozoic granitoids and metamorphic rocks in the Olary province of the Willyama block of South Australia host ore-grade amounts of U-Th-Ti and U-Fe-Ti-Th minerals. U-Pb-Th isotope analyses on zircons from all granitoids associated with the Crocker Well brannerite deposit indicate that these granitoids were intruded within a short time span,...

No abstract available....

No abstract available at this time...

Food brought to nestling Rhinoceros Auklets (Cerorhinca monocerata) was sampled by applying tape or cloth muzzles to the chicks and collecting the uningested food from the burrow daily. Limited data were also gathered for Tufted and Horned puffins (Fratercula cirrhata and F. corniculata). Auklet chicks received an average of 34.1...

The present report quantifies relations between weather and several aspects of the breeding biology of four duck species: mallard (Anas platyrhynchos), gadwall (A. strepera), blue-winged teal (A. discors), and redhead (Aythya americana). Data were obtained from two locations in North Dakota,--the J. Clark Salyer National Wildlife Refuge, intermittently during 1936-68,...

About 1100 birds of 12 spp. [Red-winged blackbird (Agelaius phoeniceus), great-tailed grackle (Quiscalus mexicanus), brown-headed cowbird (Molothrus ater), mourning dove (Zenaida macrours), Eastern meadowlark (Sturnella magna), vesper sparrow (Pooecetes gramineus), common snipe (Gallinago gallinago), blue-winged teal (Anas discors), mottled duck (Anas fulvigula), common moorhen (Gallinula chloropus), redhead (Aythya americana) and...

Geologic mapping and potassium-argon dating by R. L. Detterman, F. H. Wilson, J. E. Case, and Nora Shew in the Ugashik and western part of the Karluk quadrangles have shown that the Eocene and Oligocene volcanic arc continues into these quadrangles from the south in the Chignik and Sutwik Island...

Statistical summaries of streamflow data at 335 streamgaging sites are presented in this two volume report to aid in appraising the hydrology of river basins in Oregon. Records for 31 gaging stations were compiled into separate periods owing to changes in regulation during the period of data collection. The periods...

The oxygen isotope compositions and metamorphic mineral assemblages of hydrothermally altered rocks from the Del Puerto ophiolite and overlying volcaniclastic sedimentary rocks at the base of the Great Valley sequence indicate that their alteration occurred in a submarine hydrothermal system. Whole rock δ18O compositions decrease progressively down section (with increasing...

No abstract available....

The oil and gas industry frequently appraises undiscovered oil and gas resources on a regional basis to decide whether to start or continue exploration programs. The appraisals are of little value unless conditioned by estimates of the costs of finding and producing the resources. This paper presents an economic appraisal...

A sequential, selective extraction procedure was used to assess the effects of sulfuric acid milling on the geochemical associations of molybdenum and arsenic in a uranium ore blend, and the tailings derived therefrom. The milling process removed about 21% of the molybdenum and 53% of the arsenic initially present in...

No abstract available at this time...

Jesuits have been involved with scientific endeavors since the 16th century, although their association with seismology is more recent. What impelled Jesuit priests to also become seismologists is am matter of conjecture. Certainly the migration of missionaries to various parts of the world must have resulted in queries to their...

We report here that DSDP Site 552A, cored with the hydraulic piston corer on the west flank of Rockall Bank, recovered an undisturbed sequence of alternating white deep-sea carbonate oozes and dark-coloured layers that are rich in glacial debris. Oxygen isotope analysis of the sequence together with detailed nannofossil and...

Undisrupted periphyton communities from a N‐rich (NO3− = 63 µmol L−1) and pristine (NO3− = 2.9 µmol L−1) stream were assayed for denitrifying activity (acetylene‐blockage technique) in 40‐L chambers incubated at in situ temperature and nutrient concentrations. Nitrous oxide formation associated with periphyton from the N‐rich stream was immediate and linear (52.1 µmol N2O m−2 h−1)...