Some morphometric properties of experimentally cratered surfaces

Alfred H. Truesdell; Wendy Singers

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Some morphometric properties of experimentally cratered surfaces

Alfred H. Truesdell·Wendy Singers

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Abstract

The temperature and chemical conditions (pH, gas pressure, and ion activities) in a geothermal aquifer supplying a producing bore can be calculated from the enthalpy of the total fluid (liquid + vapor) produced and chemical analyses of water and steam separated and collected at known pressures. Alternatively, if a single water phase exists in the aquifer, the complete analysis (including gases) of a sample collected from the aquifer by a downhole sampler is sufficient to determine the aquifer chemistry without a measured value of the enthalpy. The assumptions made are that the fluid is produced from a single aquifer and is homogeneous in enthalpy and chemical composition. These calculations of aquifer chemistry involving large amounts of ancillary information and many iterations require computer methods. A computer program in PL-1 to perform these calculations is available from the National Technical Information Service as document PB-219 376.

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Alfred H. Truesdell, Wendy Singers. 1974. Some morphometric properties of experimentally cratered surfaces. https://pubs.usgs.gov/publication/70232440

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