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A study of methods of collecting and processing samples to determine whether or not gold is present in areas of moderate size was undertaken in the northwestern part of the San Juan Mountains, Colo. As part of this study, 57 samples of pan concentrates were taken from streams draining three...

This chapter classifies culvert flow into six types, gives discharge equations based on continuity and energy equations, and describes procedures for measuring peak discharges using culverts in the field. Discharge coefficients for a variety of geometries and flow types arc given. Ten examples detail step-by-step computation procedures....

Continuous measurements of stream stage are used in determining records of stream discharge. In addition a record of stream stage is useful in itself, as in designing structures affected by stream elevation or in planning the use of flood plains. This report describes instruments and structures commonly used in obtaining...

This chapter briefly describes the objectives and procedures used in obtaining streamflow records. It is considered an introduction to other chapters on surface-water techniques which treat individual procedures in greater detail....

This chapter describes application of the Manning equation to measure peak discharge in open channels. Field and office procedures limited to this method are described. Selection of reaches and cross sections is detailed, discharge equations are given, and a complete facsimile example of computation of a slope-area measurement...

Accurate measurement of water levels deeper than 1,000 feet in wells requires specialized equipment. Corrections for stretch and thermal expansion of measuring tapes must be considered, and other measuring devices must be calibrated periodically. Bore-hole deviation corrections also must be made. Devices for recording fluctuation of fluid level usually require...

When field conditions approach certain assumed conditions, the depletion in flow of a nearby stream caused by pumping a well can be calculated readily by using dimensionless curves and tables. Computations can be made of (1) the rate of stream depletion at any time during the pumping period or the...

No abstract available....

This manual describes graphical and mathematical procedures for preparing frequency curves from samples of hydrologic data. It also discusses the theory of frequency curves, compares advantages of graphical and mathematical fitting, suggests methods of describing graphically defined frequency curves analytically, and emphasizes the correct interpretations of a frequency curve....

This chapter of 'Techniques of Water-Resources Investigations' provides background material needed for understanding the statistical procedures most useful in hydrology; it furnishes detailed procedures, with examples, of regression analyses; it describes analysis of variance and covariance and discusses the characteristics of hydrologic data....

The purpose of this chapter is to describe the procedures used in the manufacture and calibration of current meters and to present in detail information pertinent to their proper maintenance and repair. Recent intensive studies on the calibration of current meters and the effects of wear of the component parts...

Extensive geochemical anomalies are present along the west side of the Sheep Creek Range in Lander County, Nev. Anomalous concentrations of zinc, arsenic, mercury, silver, copper, lead, and to some extent gold, molybdenum, and antimony occur in iron-rich material along fracture planes and in quartz veins in Paleozoic formations. A...

This manual describes the current fluorometric procedures used by the U.S. Geological Survey in dye tracer studies such as time of travel, dispersion, reaeration, and dilution-type discharge measurements. The advantages of dye tracing are (1) low detection and measurement limits and (2) simplicity and accuracy in measuring dye tracer concentrations using fluorometric techniques. The manual contains necessary...

This report describes the most outstanding floods in the United States during 1963. The three most destructive floods occurred in March from Alabama to West Virginia and Ohio, in June in Nebraska, and in August in Buffalo, N.Y.Widespread disastrous floods struck the western slopes of the Appalachian Mountains from Alabama...

Two spectrographic methods are used in mobile field laboratories of the U. S. Geological Survey. In the direct-current arc method, the ground sample is mixed with graphite powder, packed into an electrode crater, and burned to completion. Thirty elements are determined. In the spark method, the sample, ground to pass...

Estimates of monthly and annual mean discharge for five ungaged sites in the lower Columbia River are presented for water years 1928-65. These sites are Columbia River at Vancouver, Wash., Willamette River at mouth, Columbia River at St. Helens, Oreg., Columbia River at Longview, Wash., and Columbia River at mouth....