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R.O. Fournier

Publications and source records attributed to R.O. Fournier.

36 records · Page 2Linked to original sources
USGS1979

Magnesium correction to the Na K Ca chemical geothermometer

Equations and graphs have been devised to correct for the adverse effects of magnesium upon the Na-K-Ca chemical geothermometer. Either the equations or graphs can be used to determine appropriate temperature corrections for given waters with calculated Na-K-Ca temperatures > 70°C and R < 50, where R = { Mg (Mg + Ca + K) } &#xD7; 100 "> R = {Mg(Mg + Ca + K)} × 100 with cation concentrations expressed in equivalents. Waters with R > 50 are probably derived from relatively cool aquifers with temperatures approximately equal to the measured spring temperature, irrespective of much higher calculated Na-K-Ca temperatures.

Geochimica et Cosmochimica Acta↗
USGS1979

Geochemical and hydrologic considerations and the use of enthalpy-chloride diagrams in the prediction of underground conditions in hot-spring systems

Thermal water ascending in a hot-spring system may cool by conduction of heat to the surrounding rock, by boiling, by mixing with cooler water, or by a combination of these processes. Complete or partial chemical reequilibration may occur as a result of this cooling. In spite of these complexities, in many places chemical compositions of hot-spring waters may be used to estimate underground conditions. A plot of enthalpy versus chloride is particularly useful for determining underground temperatures, salinities, and boiling and mixing relations. The utility of this approach is illustrated using hot-spring composition data from Cerro Prieto, Mexico, Orakeikorako, New Zealand, and Yellowstone National Park, Wyoming. ?? 1979.

Journal of Volcanology and Geothermal Research↗
USGS1979

Chemical and isotopic prediction of aquifer temperatures in the geothermal system at Long Valley, California

Temperatures of aquifers feeding thermal springs and wells in Long Valley, California, estimated using silica and Na-K-Ca geothermometers and warm spring mixing models, range from 160/dg to about 220??C. This information was used to construct a diagram showing enthalpy-chloride relations for the various thermal waters in the Long Valley region. The enthalpy-chloride information suggests that a 282 ?? 10??C aquifer with water containing about 375 mg chloride per kilogram of water is present somewhere deep in the system. That deep water would be related to ??? 220??C Casa Diablo water by mixing with cold water, and to Hot Creek water by first boiling with steam loss and then mixing with cold water. Oxygen and deuterium isotopic data are consistent with that interpretation. An aquifer at 282??C with 375 mg/kg chloride implies a convective heat flow in Long Valley of 6.6 ?? 107 cal/s. ?? 1979.

Journal of Volcanology and Geothermal Research↗
USGS1978

Bibliography of the available data on the solubility of silica in water substance

The following bibliography represents the currently available experimental data for the solubility of silica in water substance as a function of temperature and pressure. These references were compiled by the silica subcommittee of Working Group IV at the 1977 meeting of LAPS in Moscow. The data summarized in these references cover the temperature range of 0° to 900°C at pressures from atmospheric to 1000 mega pascals. Preliminary examination of the data suggests that a good correlation of the solubility of silica can be obtained from temperature and log specific volume of water (Fig. 1). The available solubility data (log weight percent silica) tend to lie along smooth curves at constant temperature as a function of log specific volume of water. In addition the data appear to be reasonably consistent, such that a single equation can be derived that describes the solubility of quartz from 0° to 900°C at pressures up to 1000 mega pascals.

Open-File Report↗
USGS1978

A magnesium correction for the Na-K-Ca chemical geothermometer

Graphs and equations have been devised to correct for the adverse effects of magnesium upon the Na-K-Ca geothermometer. Either the graphs or equations can be used to determine temperature corrections when given waters have Na-K-Ca calculated temperatures above 70? C and values of R less than 50, where R = {Mg/(Mg + Ca + K)} x 100 in equivalents. Waters with values of R greater than 50 probably come from relatively cool aquifers with temperatures about equal to the measured spring temperature, irrespective of much higher calculated Na-K-Ca temperatures.

Open-File Report↗
USGS1977

Chemical geothermometers and mixing models for geothermal systems

Qualitative chemical geothermometers utilize anomalous concentrations of various "indicator" elements in groundwaters, streams, soils, and soil gases to outline favorable places to explore for geothermal energy. Some of the qualitative methods, such as the delineation of mercury and helium anomalies in soil gases, do not require the presence of hot springs or fumaroles. However, these techniques may also outline fossil thermal areas that are now cold. Quantitative chemical geothermometers and mixing models can provide information about present probable minimum subsurface temperatures. Interpretation is easiest where several hot or warm springs are present in a given area. At this time the most widely used quantitative chemical geothermometers are silica, Na/K, and Na-K-Ca. ?? 1976.

Geothermics↗
USGS1977

Procedure for estimating the temperature of a hot-water component in a mixed water by using a plot of dissolved silica versus enthalpy

A graphical method using a plot of dissolved silica versus enthalpy allows quick determination of the temperature of the hot-water component of a nonboiling thermal spring. The method is applicable to warm spring waters that either have not lost heat before mixing or have lost heat by separation of steam before mixing.

Journal of Research of the U.S. Geological Survey↗
USGS1976

Exchange of Na+ and K+ between water vapor and feldspar phases at high temperature and low vapor pressure

In order to determine whether gas (steam) containing a small amount of dissolved alkali chloride is effective in promoting base exchange of Na + and K + among alkali feldspars and coexisting brine or brine plus solid salt, experiments were carried out at 400–700°C and steam densities ranging down to less than 0.05. For bulk compositions rich in potassium, the low pressure results are close to previous high-pressure results in composition of the fluid and coexisting solid phase. However, when the bulk composition is more sodic, alkali feldspars are relatively richer in potassium at low pressure than at high pressure. This behaviour corresponds to enrichment of potassium in the gas phase relative to coexisting brine and precipitation of solid NaCl when the brine plus gas composition becomes moderately sodic. The gas phase is very effective in promoting base exchange between coexisting alkali feldspars at high temperature and low water pressure. This suggests that those igneous rocks which contain coexisting alkali feldspars out of chemical equilibrium either remained very dry during the high-temperature part of their cooling history or that the pore fluid was a gas containing very little potassium relative to sodium.

Geochimica et Cosmochimica Acta↗
USGS1974

Geochemical indicators of subsurface temperature: Part 1, basic assumptions

The chemical and isotopic compositions of hot-spring water and gas are used to estimate subsurface temperatures. The basic assumptions inherent in the methods are seldom stipulated. These assumptions include (1) a temperature-dependent reaction at depth, (2) a supply of the solid phase involved in the reaction to permit saturation of the constituent used for geothermometry, (3) water-rock equilibrium at depth, (4) negligible re-equilibration as the water flows to the surface, and (5) no dilution or mixing of hot and cold water. The first three assumptions are probably good for a few reactions that occur in many places. The last two assumptions probably are not valid for many hot-spring systems; information obtained is therefore for the shallower parts of those systems, or a limiting temperature (generally a minimum) is indicated.

Journal of Research of the U.S. Geological Survey↗
USGS1974

Geochemical indicators of subsurface temperature: Part 2, estimation of temperature and fraction of hot water mixed with cold water

The water in many warm springs with large rates of flow consists of mixtures of hot water that has come from depth and of shallow cold water. Under favorable conditions the original temperature of the hot water and the fraction of the cold water in the mixture can be estimated by using the measured temperature and silica content of the warm spring water and the temperature and silica content of nonthermal water in the region. The method has been applied with apparent success at Yellowstone National Park.

Wyoming↗
USGS1973

An empirical NaKCa geothermometer for natural waters

An empirical method of estimating the last temperature of water-rock interaction has been devised. It is based upon molar Na, K and Ca concentrations in natural waters from temperature environments ranging from 4 to 340°C. The data for most geothermal waters cluster near a straight line when plotted as the function log ( Na K ) + &#x3B2; log [ &#x221A; (Ca) Na ] "> log (NaK) + β log [ √(Ca)Na] vs reciprocal of absolute temperature, where β is either 1 3 "> 13 or 4 3 "> 43 depending upon whether the water equilibrated above or below 100°C. For most waters tested, the method gives better results than the Na K "> NaK methods suggested by other workers. The ratio Na K "> NaK should not be used to estimate temperature if &#x221A; ( M Ca ) M Na "> √ (MCa)MNa is greater than 1. The Na K "> NaK values of such waters generally yield calculated temperatures much higher than the actual temperature at which water interacted with the rock. A comparison of the composition of boiling hot-spring water with that obtained from a nearby well (170°C) in Yellowstone Park shows that continued water-rock reactions may occur during ascent of water even though that ascent is so rapid that little or no heat is lost to the country rock, i.e. the water cools adiabatically. As a result of such continued reaction, waters which dissolve additional Ca as they ascend from the aquifer to the surface will yield estimated aquifer temperatures that are too low. On the other hand, waters initially having enough Ca to deposit calcium carbonate during ascent may yield estimated aquifer temperatures that are too high if aqueous Na and K are prevented from further reaction with country rock owing to armoring by calcite or silica minerals. The Na-K-Ca geothermometer is of particular interest to those prospecting for geothermal energy. The method also may be of use in interpreting compositions of fluid inclusions.

Wyoming↗
USGS1973

More on noble gases in Yellowstone National Park hot waters

Water and gas samples from research wells in hydrothermal areas of Yellowstone National Park, U.S.A., have been mass spectrometrically analyzed for their rare gas contents and isotopic composition. In agreement with previous findings, the rare gases have been found to originate from infiltrating run-off water, saturated with air at 10 to 20°C. The atmospheric rare gas retention values found for the water varied between 3 and 87 per cent. The fine structure of the Ar, Kr and Xe abundance pattern in the water reveals fraotionational enrichment of the heavier gases due to partial outgassing of the waters. Radiogenic He and Ar have been detected. No positive evidence for magmatic water contribution has been found. Nevertheless, additions of magmatic waters free of rare gas can not be excluded, but if present the proportion is significantly less than 13 to 36 per cent.

Wyoming↗
USGS1970

Chemical indicators of subsurface temperature applied to hot spring waters of Yellowstone National Park, Wyoming, U.S.A.

Under favorable conditions the chemistry of hot springs may give reliable indications of subsurface temperatures and circulation patterns. These chemical indicators can be classified by the type of process involved: Indicator Dominant Process The silica geothermometer Solution-precipitation Alkali ratios Ion exchange Cl/(HCO 3 + CO 3 ) ratio Rock alteration by dissolved CO 2 Relative concentration of Partitioning owing to subsur- volatiles in spring water face boning All these indicators have certain limitations. The silica geothermometer gives results independent of the local mineral suite and gas partial pressures, but may be affected by dilution. Alkali ratios are strongly affected by the local mineral suite and the formation of complex ions. Carbonate-chloride ratios are strongly affected by subsurface P CO2 . The relative concentration of volatiles can be very misleading in high-pressure liquid systems. In Yellowstone National Park most thermal waters issue from hot, shallow aquifers with pressures in excess of hydrostatic by 2 to 6 bars and with large flows (the flow of hot spring water from the Park is greater than 4000 liters per second). These conditions should be ideal for the use of chemical indicators to estimate aquifer temperatures. In five drill holes aquifer temperatures were within 2°C of that predicted from the silica content of nearby hot springs; the temperature level off at a lower value than predicted in only one hole, and in four other holes drilling was terminated before the predicted aquifer temperature was reached. The temperature-Na/K ratio relationship does not follow any published experimental or empirical curve for water-feldspar or water-clay reactions. We suspect that ion exchange reactions involving zeolites in the Yellowstone rocks result in higher Na/K ratios at given temperatures than result from feldspar or clay reactions. Comparison of SiO 2 and Cl/(HCO 3 + CO 3 ) suggest that because of higher subsurface P CO2 in Upper Geyser Basin a given Cl/(HCO 3 + CO 3 ) ratio there means a higher temperature than in Lower Geyser Basin. No correlation was found in Yellowstone Park between the subsurface regions of highest temperature and the relative concentration of volatile components such as boron and ammonia.

Wyoming↗
USGS1964

The system K2Mg2(SO4)3 (langbeinite)-K2Ca2(SO4)3 (calcium-langbeinite)

The join between the compositions K 2 Mg 2 (SO 4 ) 3 and K 2 Ca 2 (SO 4 ) 3 was studied by means of high-temperature equilibrium quenching techniques and by means of a heating stage mounted on an X-ray diffractometer. Complete solid solution exists in the system, but at 25°C members of the solid solution series are isometric only in the composition range 0–73·5 wt. per cent K 2 Ca 2 (SO 4 ) 3 . At compositions richer in K 2 Ca 2 (SO 4 ) 3 than 73·5 wt. per cent, members of the series are optically biaxial. At higher temperatures members of the solid solution series are isometric at successively more calcium-rich compositions and pure K 2 Ca 2 (SO 4 ) 3 is isometric above about 200 ± 2°C. The system is not binary, as mixtures richer in K 2 Ca 2 (SO 4 ) 3 than 42 wt. per cent decompose with the formation of liquid and CaSO 4 .

Journal of Inorganic and Nuclear Chemistry↗
USGS1962

The solubility of quartz in water in the temperature interval from 25° to 300° C

The solubility of quartz in water was investigated by three sets of experiments at 1000 atm P H 2 O and temperatures ranging from 45&deg; to 300&deg;C at water pressures appropriate for the coexistence of three phases, gaseous water, liquid, and quartz, at temperatures ranging from 69&deg; to 240&deg;C a long term study of the dissolution of quartz grains which were continuously tumbled in water at room temperature. Saturated silica solutions in equilibrium with quartz were obtained in a few days at temperatures above 100&deg;C. Equilibrium is shown by reproducible results for runs of different durations and by the precipitation of quartz from initially supersaturated solutions. The differential heat of solution derived from the data obtained at 1000 atm pressure is 5.38 kcal/mole. At room temperature and pressure, highly supersaturated silica solutions were obtained by continuously rotating quartz grains and water in plastic bottles at 75 rev/min. In one run the amount of silica in solution increased to a maximum value of 395 p.p.m. after 370 days. Another run reached 80 p.p.m. silica after 386 days and then dropped to 6 p.p.m. silica. It is concluded that quartz was precipitated at room temperature from this supersaturated solution and that 6 p.p.m. is essentially the true solubility of quartz at 25&deg;C. In contrast to the runs rotated at 75 rev/min, quartz grains, and also silica glass grains, continuously rotated in water at rev/min, each contributed less than 1 p.p.m. colorimetric silica into solution after 1 year. Thus, vigorous agitation of the liquid is necessary to remove dissolved silica from the vicinity of surfaces of both quartz and glass. Two significant factors that may have contributed to the formation of supersaturated silica solutions in the runs rotated at 75 rev/min at room temperature are stresses and structural irregularities at the surfaces of the crushed quartz grains, which contributed silica into solution more readily than well crystallized quartz the very slow rate at which dissolved silica polymerizes to species appropriate to act as nuclei for quartz growth. At the termination of the runs rotated at 75 rev/min, spikelike projections were present on many of the quartz grains. These are interpreted as indicating that abrasion was not the dominant cause for the great supersaturations which were obtained.

Geochimica et Cosmochimica Acta↗