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Publication Extents

Not all publications have extents, not all extents are completely accurate
Distribution of gold, tellurium, silver, and mercury in part of the Cripple Creek district, Colorado
Garland Bayard Gott, J. H. McCarthy, G.H. Van Sickle, J. B. McHugh
1967, Circular 543
Geochemical exploration studies were undertaken in the Cripple Creek district to test the possibility that large low-grade gold deposits might be found. Surface rock samples taken throughout the district indicate that the volcanic rocks between the productive veins contain an average of about 0.6 ppm (part per million) gold. In...
General field and office procedures for indirect discharge measurements
M. A. Benson, Tate Dalrymple
1967, Techniques of Water-Resources Investigations 03-A1
The discharge of streams is usually measured by the current-meter method. During flood periods, however, it is frequently impossible or impractical to measure the discharges by this method when they occur. Consequently, many peak discharges must be determined after the passage of the flood by indirect methods, such as slope-area,...
Economic significance of revised age relations of rocks in the Cornucopia mining district, Elko County, Nevada
Robert Roy Coats
1967, Circular 549
Recent geologic work in the Cornucopia mining district, a small silver-gold mining district in northwestern Elko County, Nev., has resulted in significant revision of the geological interpretation. Rocks formerly thought to be premineralization in age, but unmineralized, are now known to be postmineral extrusives, resting unconformably on the altered andesite...
A simple mercury vapor detector for geochemical prospecting
William W. Vaughn
1967, Circular 540
The detector utilizes a large-volume atomic-absorption technique for quantitative determinations of mercury vapor thermally released from crushed rock. A quartz-enclosed noble-metal amalgamative stage, which is temperature controlled and is actuated by a radio-frequency induction heater, selectively traps the mercury and eliminates low-level contamination. As little as 1 part per billion...
Bedded barite in East Northumberland Canyon, Nye County, Nevada
Daniel R. Shawe, F. G. Poole, Donald Albert Brobst
1967, Circular 555
Bedded barite has been identified in the course of stratigraphic studies by the U.S. Geological Survey in and near East Northumberland Canyon, Toquima Range, Nye County, Nev. The barite beds are interlayered in black chert of probable Ordovician age. The barite rock is mostly dark gray and massive, has a...
Are we running out of water?
Raymond L. Nace
1967, Circular 536
Water supplies are not running out, but time is getting short to stem waste of water and destructive exploitation of the environment before harm is done that may be irreparable. Most of the world's water is oceanic brine. Of the waters on the land, most is frozen in Antarctica and...
Determination of gold in geologic materials by solvent extraction and atomic-absorption spectrometry
Claude Huffman, J.D. Mensik, L.B. Riley
1967, Circular 544
The two methods presented for the determination of traces of gold in geologic materials are the cyanide atomic-absorption method and the fire-assay atomic-absorption method. In the cyanide method gold is leached with a sodium-cyanide solution. The monovalent gold is then oxidized to the trivalent state and concentrated by extracting into...
Measurement of peak discharge at dams by indirect methods
Harry Hulsing
1967, Techniques of Water-Resources Investigations 03-A5
This chapter describes procedures for measuring peak discharges using dams, weirs, and embankments. Field and office procedures limited to this method are described. Discharge coefficients and formulas are given for three general classes of weirs-sharp-crested, broad-crested, and round-crested-and for highway embankments and weirs of unusual shape. The effects of...
Flood information for flood-plain planning
Conrad D. Bue
1967, Circular 539
Floods are natural and normal phenomena. They are catastrophic simply because man occupies the flood plain, the highwater channel of a river. Man occupies flood plains because it is convenient and profitable to do so, but he must purchase his occupancy at a price-either sustain flood damage, or provide flood-control...
Marine sediment sample preparation for analysis for low concentrations of fine detrital gold
H. Edward Clifton, Arthur Hubert, R. Lawrence Phillips
1967, Circular 545
Analyses by atomic absorption for detrital gold in more than 2,000 beach, offshore, marine-terrace, and alluvial sands from southern Oregon have shown that the values determined from raw or unconcentrated sediment containing small amounts of gold are neither reproducible nor representative of the initial sample. This difficulty results from a...