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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 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....

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...

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...

The reported gold contents of meteorites range from 0.0003 to 8.74 parts per million. Gold is siderophilic, and the greatest amounts in meteorites are in the iron phases. Estimates ,of the gold content of the earth's crust are in the range of 0.001 to 0.006 parts per million....

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 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...

The vertical mass transfer coefficient and particle fall velocity were determined in an open channel shear flow. Three dispersants, dye, fine sand and medium sand, were used with each of three flow conditions. The dispersant was injected as a continuous line source across the channel and downstream concentration profiles were...