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John L. Haas

Publications and source records attributed to John L. Haas.

11 recordsLinked to original sources
USGS1981

Thermodynamic tabulations for selected phases in the system CaO-Al 2 O 3 -SiO 2 -H 2 at 101.325 kPa (1 atm) between 273.15 and 1800 K

The standard thermodynamic properties of phases in the lime‐alumina‐silica‐ water system between 273.15 and 1800 K at 101.325 kPa (1 atm) were evalated from published experimental data. Phases included in the compilation are boehmite, diaspore, gibbsite, kaolinite, dickite, halloysite, andalusite, kyanite, sillimanite, Ca‐Al cliniopyroxene, anorthite, gehlenite, grossular, prehnite, zoisite, margarite, wollastonite, cyclowollastonite ( = pseudowollastonite), larnite, Ca olivine, hatrurite, and rankinite. The properties include heat capacity, entropy, relative enthalpy, and the Gibbs energy function of the phases and the enthalpies, Gibbs energies, and equilibrium constants for formation both from the elements and the oxides. Tabulated values are given at 50 K intervals with the 2‐sigma confidence limit at 250 K intervals. Summaries for each phase give the temperature‐ dependent functions for heat capacity, entropy, and relative enthalpy and the experimental data used in the final evaluation.

Journal of Physical and Chemical Reference Data↗
USGS1978

Models for calculating density and vapor pressure of geothermal brines

In a model for estimating density of a brine, the density of a natural brine at a known temperature, pressure, and composition can be calculated from the densities of the component salt solutions in the complex brine. A model for estimating vapor pressure requires two direct or indirect estimates of the vapor pressure and uses a published "reference-substance principle" to extrapolate,; these data 200° to 300° above the temperature of the highest observation. The methods can be used to estimate the partial molal volume and partial molal enthalpy of H 2 O in the natural brine and the partial molal volume change and partial molal heat change for the H2O component in the vaporization process. The equations for density and vapor pressure and the derived thermochemical properties will help in designing turbines for operation with geothermal and geopressured brines, in optimizing production conditions, and in physical and chemical modeling of a geothermal reservoir.

Journal of Research of the U.S. Geological Survey↗
USGS1971

The effect of salinity on the maximum thermal gradient of a hydrothermal system at hydrostatic pressure

The effect of salinity on the temperature-depth relations of a brine of constant composition, enclosed in a vein system, but freely connected to the surface, and everywhere at the boiling point for the hydrostatic head, was calculated by using a mathematical model. The Na-Ca-K-Cl brines which are found in thermal springs and in fluid inclusions in ore minerals were approximated by the available data for vapor-saturated NaCl-H 2 O solutions. In general, the results are similar to those calculated by D. E. White in 1968 for H 2 O, except that the gradients are steeper because of the increase in density and the decrease in vapor pressure caused by the dissolved salt. As a practical rule, the depth to an isotherm in a 5, 10, 15, 20, and 25 wt percent NaCl brine system is, respectively, 92, 84, 77, 70, and 63 percent (+ or -2 percent) of the depth to the same isotherm in an H 2 O system. From the data presented, the minimum depth to the growth site of crystals containing fluid inclusions which indicate boiling of the brine can be estimated. Among other applications, these results are useful toward the understanding of the behavior of brines in geothermal areas which may or may not contain compositional stratification.

Economic Geology↗