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Specific yield: compilation of specific yields for various materials

January 1, 1994

Specific yield is defined as the ratio of (1) the volume of water that a saturated rock or soil will yield by gravity to (2) the total volume of the rock or soft. Specific yield is usually expressed as a percentage. The value is not definitive, because the quantity of water that will drain by gravity depends on variables such as duration of drainage, temperature, mineral composition of the water, and various physical characteristics of the rock or soil under consideration. Values of specific yields nevertheless offer a convenient means by which hydrologists can estimate the water-yielding capacities of earth materials and, as such, are very useful in hydrologic studies.

The present report consists mostly of direct or modified quotations from many selected reports that present and evaluate methods for determining specific yield, limitations of those methods, and results of the determinations made on a wide variety of rock and soil materials. Although no particular values are recommended in this report, a table summarizes values of specific yield, and their averages, determined for 10 rock textures. The following is an abstract of the table.


Citation Information

Publication Year 1967
Title Specific yield: compilation of specific yields for various materials
DOI 10.3133/wsp1662D
Authors A.I. Johnson
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Water Supply Paper
Series Number 1662
Index ID wsp1662D
Record Source USGS Publications Warehouse