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A.H. Truesdell

Publications and source records attributed to A.H. Truesdell.

49 records · Page 3Linked to original sources
USGS1973

Production of superheated steam from vapor-dominated geothermal reservoirs

Vapor-dominated geothermal systems such as Larderello, Italy, The Geysers, California, and Matsukawa, Japan yield dry or superheated steam when exploited. Models for these systems are examined along with production data and the thermodynamic properties of water, steam and rock. It is concluded that these systems initially consist of a water and steam filled reservoir, a water-saturated cap rock, and a water or brine-saturated deep reservoir below a water table. Most liquid water in all parts of the system is relatively immobilized in small pores and crevices; steam dominates the large fractures and voids of the reservoir and is the continuous, pressure-controlling phase. With production, the pressure is lowered and the liquid water boils, causing massive transfer of heat from the rock and its eventual drying. Passage of steam through already dried rock produces superheating. After an initial vaporization of liquid water in the reservoir, the decrease in pressure produces increased boiling below the deep water table. With heavy exploitation, boiling extends deeper into hotter rock and the temperature of the steam increases. This model explains most features of the published production behavior of these systems and can be used to guide exploitation policies.

Geothermics↗
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↗
USGS1969

Ion association in natural brines

Natural brines, both surface and subsurface, are highly associated aqueous solutions. Ion complexes in brines may be ion pairs in which the cation remains fully hydrated and the bond between the ions is essentially electrostatic, or coordination complexes in which one or more of the hydration water molecules are replaced by covalent bonds to the anion. Except for Cl − , the major simple ions in natural brines form ion pairs; trace and minor metals in brines form mainly coordination complexes. Limitations of the Debye-Hückel relations for activity coefficients and lack of data on definition and stability of all associated species in concentrated solutions tend to produce underestimates of the degree of ion association, except where the brines contain a very high proportion of Cl − . Data and calculations on closed basin brines of highly varied composition have been coupled with electrode measurements of single-ion activities in an attempt to quantify the degree of ion association. Such data emphasize the role of magnesium complexes. Trace metal contents of closed basin brines are related to complexes formed with major anions. Alkaline sulfo- or chlorocarbonate brines (western Great Basin) carry significant trace metal contents apparently as hydroxides or hydroxy polyions. Neutral high chloride brines (Bonneville Basin) are generally deficient in trace metals. With a knowledge of the thermodynamic properties of a natural water, many possible reactions with other phases (solids, gases, other liquids) may be predicted. A knowledge of these reactions is particularly important in the study of natural brines which may be saturated with many solid phases (silicates, carbonates, sulfates, etc.), which may have a high pH and bring about dissolution of other phases (silica, amphoteric hydroxides, CO 2 , etc.), and which because of their high density may form relatively stable interfaces with dilute waters.

Chemical Geology↗
USGS1969

Interstitial brines in playa sediments

Study of several closed drainages in the Great Basin has shown that the interstitial solutions of shallow, fine-grained playa deposits store a large quantity of dissolved solids and are often more concentrated than associated lakes and ponds, except in peripheral zones of stream or ground-water inflow. These interstitial fluids, when compared with local runoff, impoundments, or spring waters, commonly have a distinctive ionic composition which sometimes cannot be explained by either simple mixing of surface and subsurface inflow or by evaporative concentration. At Abert Lake, Oregon, the interstitial solute concentrations increased with depth to values as much as five times greater than the lake, except where springs indicate significant ground-water input. Where Na + , Cl, and CO 2 species constitute more than 90% of the solutes, Na + Cl − "> Na+Cl− ratios in the lake water are lower than in interstitial solutions of bottom cores and higher than in playa fluids. At the same time, Na + K + "> Na+K+ ratios are highest in the fluids of lake bottom muds and lowest in playa interstitials. In deeper playa profiles, interstitial Na + Cl − "> Na+Cl− tended to decrease with depth (5 ft. maximum). In the Abert Lake area, as in other parts of the western Great Basin, Na + Cl − "> Na+Cl− ratios are indicative of total CO 2 in solution and the effects of organic decay in surficial sediments. These ratios, coupled with data on silica and bulk density, show that higher P CO2 accompanying decay promotes silicate dissolution and hydrogen ion exchange, stripping alkalis from sediment which had preferentially adsorbed K + when entering the lake. On subsequent loss of pore fluid in the playa regime, silica initially released to solution in the lake environment is readsorbed on dissolution products.

Oregon↗
USGS1968

Dissociation constants of KSO 4 - from 10°-50°C

A cell without liquid junction was used to obtain dissociation constants for the reaction: KSO 4 − = K + + SO 4 2− . At 10°, 25°, 38° and 50°C, values for K diss KSO 4 − are, respectively, 0.19 5 , 0.14 2 , 0.11 7 , and 0.09 5 . At 25°C, , and values for the KSO 4 − ion are −245.96 and −274.02 kcal mole −1 , and S ° is +42.3 cal mole −1 deg −1 .

Geochimica et Cosmochimica Acta↗
USGS1967

Borate mineral assemblages in the system Na2O-CaO-MgO-B2O3-H2O

The significant known hydrated borate mineral assemblages (principally of the western United States) in the system Na 2 O-CaO-MgO-B 2 O 3- H 2 O are expressible in three ternary composition diagrams. Phase rule interpretation of the diagrams is consistent with observation, if the activity of H 2 O is generally considered to be determined by the geologic environment. The absence of conflicting tie-lines on a diagram indicates that the several mineral assemblages of the diagram were formed under relatively narrow ranges of temperature and pressure. The known structural as well as empirical formulas for the minerals are listed, and the more recent (since 1960) crystal structure findings are discussed briefly. Schematic Gibbs free energy-composition diagrams based on known solubility-temperature relations in the systems Na 2 B 4 O 7 -H 2 O and Na 2 B 4 O 7 -NaCl-H 2 O, are highly useful in the interpretation and prediction of the stability relations in these systems; in particular these diagrams indicate clearly that tincalconite, although geologically important, is everywhere a metastable phase. Crystal-chemical considerations indicate that the same thermodynamic and kinetic behavior observed in the Na 2 B 4 O 7 -H 2 O system will hold in the Ca 2 B 6 O 11 -H 2 O system. This conclusion is confirmed by the petrologic evidence. The chemical relations among the mineral assemblages of a ternary diagram are expressed by a schematic “activity-activity” diagram. These activity-activity diagrams permit the tracing-out of the paragenetic sequences as a function of changing cation and H 2 O activities.

Geochimica et Cosmochimica Acta↗
USGS1965

Glass electrode determination of sodium in closed basin waters

Because of its direct relation to total dissolved solids content, sodium concentration is the most useful single hydrochemical parameter of closed basin waters in the western United States. Therefore, it is advantageous to have a rapid method for sodium determination which could be readily adapted to field use. Accordingly, thirty waters of highly variable concentration and anionic composition from the western Great Basin have been analyzed with a sodium-sensitive glass electrode. Na + values ranged from 10 to 130,000 ppm in waters containing from 102 to 401,000 ppm total dissolved solids. The electrode values were compared with conventional sodium determinations; results differed by as much as 11 per cent, although over two-thirds were within 5 per cent. No significant relation was found between the glass electrode and conventional method differences and the total dissolved solids or sodium concentration. The comparative accuracy of electrode and conventional procedures was checked, employing solutions of known sodium concentration. It was concluded that for the analysis of sodium in natural waters the glass electrode method offers results comparable in accuracy to those obtained by conventional methods, but with increased simplicity, and therefore the possibility of rapid, accurate field measurements.

Geochimica et Cosmochimica Acta↗
USGS1963

Phosphate glass electrode with good selectivity for alkaline-earth cations

A phosphate glass has been found to have a significant electrode specificity toward alkaline-earth ions. The order of selectivity is 2H + > Ba ++ > Sr ++ > Ca ++ > 2K + > 2Na + > Mg ++ . Exchange properties are discussed in relation to possible structure. Its use to determine activity of Ca ++ in natural systems containing Mg ++ is suggested.

Science↗
USGS1962

Study of natural glasses through their behaviour as membrane electrodes

THE low-temperature chemical alteration of natural glass occurs in two stages: an initial stage in which it remains glassy but absorbs as much as 6 per cent water 1 , and a final stage in which devitrification to clay minerals, with release of silica, occurs 2,3 . During the first stage the composition of the glass may change, with gain of K 2 O and water and loss of Na 2 O (Smith, R. L., personal communication). This change is due to ion exchange.

Nature↗
USGS1962

Glass electrodes sensitive to divalent cations

Glass electrodes suitable for measurement of divalent cations have been made and tested. Empirical and theoretical electrode equations have been presented to describe electrode behavior in a variety of aqueous solutions. Most electrodes show response interpretable as showing nearly ideal solid-solution behavior of the cations in the glass surface. The electrodes should be useful in the measurement of divalent-cation activities in natural waters and biological fluids, and useful in general analytical chemistry.

Science↗