... Biochemistry 5:467-477. Page 9. Metal Toxicity to D. desulfuricans 49 Hammack, RW, and Edenbo... more ... Biochemistry 5:467-477. Page 9. Metal Toxicity to D. desulfuricans 49 Hammack, RW, and Edenbom, HM 1992. The removal of nickel from mine waters using bacte-rial sulfate reduction. Appl. Microbiol. Biotechnol. 37:674-678. ...
The solubility of toluene has been measured in distilled water, and in various inorganic salt sol... more The solubility of toluene has been measured in distilled water, and in various inorganic salt solutions. Values of the Setschenow constant, K(S), which quantify toluene solubility versus salt concentration, have been determined for each salt. Values of K(S) are compared to the activity of water for the salt solutions. Data from this study, consistent with earlier data, suggests that the effects of salts upon toluene solubility are non-additive. This contrasts the additive behavior of inorganic salts upon the solubility of nonpolar organic compounds, such as benzene and naphthalene, reported in the literature. Specific interaction between slightly polar toluene and ions in solution is suggested as a possible explanation for the non-additive effect of salts on the solubility of toluene.
Previous work on adsorption of oxalate at aluminosilicate surfaces suggests that maximum adsorpti... more Previous work on adsorption of oxalate at aluminosilicate surfaces suggests that maximum adsorption occurs through a bidentate attachment of the organic ligand, at nearneutral pH. Rates of ligand-promoted dissolution are expected to be greatest at this pH as well. We tested this model by measuring oxalate adsorption on the surface of andesine (An 47 ), in solutions of pH 3-5 and total oxalate concentrations of 0-8 mM. Contrary to expectation, the greatest adsorption density of 24 µmol m -2 total oxalate was observed at pH 3 and 8 mM total oxalate. Adsorption is dependent upon the activities of both oxalate (C 2 O 4 2-) and bioxalate (HC 2 O 4 -) in solution and can be modeled with either a two-term Langmuir or a two-term Freundlich isotherm. A Freundlich adsorption model provided the best fit to rate data because it was not constrained to a finite number of adsorption sites, as was the Langmuir model. The two-term ligand adsorption model was incorporated into a rate model:
Sorption partition coeffkients between water and organic carbon (K,) for deuterated benzene, tolu... more Sorption partition coeffkients between water and organic carbon (K,) for deuterated benzene, toluene, and etttylkmz.ene have been estimated by measuring values of the octanol-water partition coefficient (Kc,,) and HPLC retention factors (k'), which correlate closely to values of Kcc. Measured values of log Kc,, for nondeuterated and de&rated toluene are 2.77 (i 0.02) and 2.78 (It O&t), respectively, indicating that within ,experimental error, log Kc, for deuterated and nondeuterated toluene are the same. The HPLC method provides greater precision, and yields values of A log Kcc (= log Kcc [deuterated] -log Kcc [non-deuterated]) of -0.021 (* 0.001) for benzene, -0.028 (rt 0.002) for toluene, and -0.035 (rt 0.003) for ethylbenzene. The small values of A log Kcc demonstrates that deuterated compounds am excellent tracers for the hydrologic behavior of ground water contaminants. 01997
This study investigates the carbon isotope systematics of benzene, toluene, ethylbenzene, and xyl... more This study investigates the carbon isotope systematics of benzene, toluene, ethylbenzene, and xylene monoaromatic hydrocarbons (BTEX) with regard to an improved understanding of the behavior of these compounds in the subsurface, particularly during remediation processes. We found that fractionation eects due to vaporization are small and positive for all compounds studied (D 13 C vapor±liquid Q+0.2-), and that fractionation eects due to soil adsorption are also likely to be small ( 13 C-labeled compounds cannot be resolved from unlabeled compounds by HPLC). We also evaluated use of the isotopic composition of contaminants as tracers of source and migration in the subsurface by performing a survey of the bulk isotopic composition of commercially available sources of BTEX. The results indicate that a wide range of d 13 C values exist (e.g., benzene, À23.87-to À29.40-). Our work suggests that stable C isotope analysis has great potential for qualifying, and possibly quantifying, the subsurface processes aecting contaminant concentrations. In particular, stable isotope analysis may be especially bene®cial for monitoring the ecacy of abiological and biological remediation eorts. #
Page 142. Chapter 10 x Pore Fluid Chemistry of a Pressure Seal Zone, Moore-SamsMorganza Gas Fiel... more Page 142. Chapter 10 x Pore Fluid Chemistry of a Pressure Seal Zone, Moore-SamsMorganza Gas Field, Tuscaloosa Trend, Louisiana Thomas P. Ross Arthur W. Rose Simon R. Poulson Pennsylvania State University University ...
Unlike the majority of the water in the flooded mine complex of Butte Montana, which includes the... more Unlike the majority of the water in the flooded mine complex of Butte Montana, which includes the highly acidic Berkeley pit lake, groundwater in the flooded West Camp underground mine workings has a circum-neutral pH and contains at least 8 mM aqueous sulfide. This article examines the geochemistry and stable isotope composition of this unusual H 2 S-rich mine water, and also discusses problems related to the colorimetric analysis of sulfide in waters that contain FeS (aq) cluster compounds. The West Camp mine pool is maintained at a constant elevation by continuous pumping, with discharge water that contains elevated Mn (90 mM), Fe (16 mM), and As (1.3 mM) but otherwise low metal concentrations. Dissolved inorganic carbon in the mine water is in chemical and isotopic equilibrium with rhodochrosite in the mineralized veins. The mine water is under-saturated with mackinawite and amorphous FeS, but is supersaturated with Cu-and Zn-sulfides. However, voltammetry studies show that much of the dissolved sulfide and ferrous iron are present as FeS (aq) cluster molecules: as a result, the free H 2 S + HS À concentration of the West Camp water is poorly constrained. Concentrations of dissolved sulfide determined by colorimetry were lower than gravimetric assays obtained by AgNO 3 addition, implying that the FeS (aq) clusters are not completely extracted by the Methylene Blue reagent. In contrast, the clusters are quantitatively extracted as Ag 2 S after addition of AgNO 3 . Isotopic analysis of co-existing aqueous sulfide and sulfate confirms that the sulfide was produced by sulfate-reducing bacteria (SRB). The H 2 S-rich mine water is not confined to the immediate vicinity of the extraction well, but is also present in flooded mine shafts up to 3 km away, and in samples bailed from mine shafts at depths up to 300 m below static water level. This illustrates that SRB are well established throughout the southwestern portion of the extensive (>15 km 3 ) Butte flooded mine complex.
Oxygen isotope analyses of water, and carbon isotope analyses of dissolved inorganic carbon (DIC)... more Oxygen isotope analyses of water, and carbon isotope analyses of dissolved inorganic carbon (DIC), CO*(g), and CHh(@ have been performed on samples from normal and overpressured horizons in the Louisiana Gulf Coast. S OsMow values of the waters range from -2.2 to + 8.7%. Consideration of the aI80 values, the chemical composition of the waters, and the water and gas production values indicate that mixing with a low salinity, isotopically light water has taken place. Mixing lines suggest that the isotopically light component may be water vapor condensed during gas production, with a Rayleigh fractionation process accompanying vapor condensation, rather than shallow groundwater. Mixing lines suggest that all formation waters have 6"O x + 8%0, which is normal for deep, basinal waters, although Cl-concentrations indicate there are 2 water populations (with approximately 35,000 mg/l and 15,000 to 20,000 mg/l). There appears to be no systematic difference between the overpressured and normally pressured samples, or between samples from different fields. 613C Pea values of DIC range from -10.6 to -3.2%. G'3Cp~s values of CH4 range from -43.9 to -40.8%,,, and 613C ~,,a values of CO2 range from -8.8 to -6.3L, indicating that these gases have a thermogenic origin. Significant isotopic differences are observed between the Moore-Sams and Morganza samples which suggest that the Morganza gases were produced at higher temperatures and/or by the decomposition of more mature source material. The CO* and DIC are not in isotopic equilibrium with calcite and dolomite cements immediately above and below the seal, suggesting that precipitation of calcite and dolomite took place in an earlier event(s). The DIC of most samples is at, or near, isotopic equilibrium with COz, although it appears that some samples have derived a significant component of DIC from isotopically heavier samples located both higher and lower in the section. The lack of isotopic equilibrium between DIC and CO> for some samples suggests either that some water samples have little or no contact with coexisting gas samples, or that a dynamic process is taking place that prevents equilibrium being achieved.
The oxygen isotope fractionation between NaCO~-and water in the presence of NaC1 concentrations u... more The oxygen isotope fractionation between NaCO~-and water in the presence of NaC1 concentrations up to 4 M at temperatures between 100 ° and 300 °C has been investigated using a new, high-temperature titration technique. Dissolved carbonate is equilibrated at temperature with the experimental solution, and then the carbonate is quantitatively precipitated as BaCO3 by the injection of BaC12 solution at temperature. The isotopic composition of the BaCO3 reflects the composition of the free water, and hence reflects changes in the oxygen isotope composition of the free water due to the presence of NaC1. Under the experimental conditions used in this study, NaCO3-is the dominant dissolved carbonate species, and the oxygen isotope fractionation between NaCO~-and water between 100 ° and 300°C is given by: 1000 In ~=2.7( 106T-2)-5.7
PDF Click to view page images in PDF format. Volume: 80 ( 1996 ). Issue: 7. (July). First Page: 1... more PDF Click to view page images in PDF format. Volume: 80 ( 1996 ). Issue: 7. (July). First Page: 1045. Last Page: 1063. Title: Diagenesis, Compaction, and Fluid Chemistry Modeling of a Sandstone Near a Pressure Seal: Lower Tuscaloosa Formation, Gulf Coast. ...
Previous work on adsorption of oxalate at aluminosilicate surfaces suggests that maximum adsorpti... more Previous work on adsorption of oxalate at aluminosilicate surfaces suggests that maximum adsorption occurs through a bidentate attachment of the organic ligand, at nearneutral pH. Rates of ligand-promoted dissolution are expected to be greatest at this pH as well. We tested this model by measuring oxalate adsorption on the surface of andesine (An 47 ), in solutions of pH 3-5 and total oxalate concentrations of 0-8 mM. Contrary to expectation, the greatest adsorption density of 24 µmol m -2 total oxalate was observed at pH 3 and 8 mM total oxalate. Adsorption is dependent upon the activities of both oxalate (C 2 O 4 2-) and bioxalate (HC 2 O 4 -) in solution and can be modeled with either a two-term Langmuir or a two-term Freundlich isotherm. A Freundlich adsorption model provided the best fit to rate data because it was not constrained to a finite number of adsorption sites, as was the Langmuir model. The two-term ligand adsorption model was incorporated into a rate model:
Many rivers undergo diel (24-h) concentration fluctuations of pH, dissolved gases, trace metals, ... more Many rivers undergo diel (24-h) concentration fluctuations of pH, dissolved gases, trace metals, nutrients, and other chemical species. A study conducted in 1994 documented such behavior in the upper Clark Fork River, Montana, a stream whose headwaters have been severely ...
... 2SO 4 2− + 16H + (3)Fe 3+ + H 2 O + hυ → Fe 2+ + H + + OH Unlike Fe(II) oxidation, oxidation ... more ... 2SO 4 2− + 16H + (3)Fe 3+ + H 2 O + hυ → Fe 2+ + H + + OH Unlike Fe(II) oxidation, oxidation of pyrite by Fe 3+ is rapid at low pH and will take place in the presence or absence of bacteria ( [Garrels and Thompson, 1960] , [Singer and Stumm, 1970] , [Williamson and Rimstidt ...
Sorption partition coeffkients between water and organic carbon (K,) for deuterated benzene, tolu... more Sorption partition coeffkients between water and organic carbon (K,) for deuterated benzene, toluene, and etttylkmz.ene have been estimated by measuring values of the octanol-water partition coefficient (Kc,,) and HPLC retention factors (k'), which correlate closely to values of Kcc. Measured values of log Kc,, for nondeuterated and de&rated toluene are 2.77 (i 0.02) and 2.78 (It O&t), respectively, indicating that within ,experimental error, log Kc, for deuterated and nondeuterated toluene are the same. The HPLC method provides greater precision, and yields values of A log Kcc (= log Kcc [deuterated] -log Kcc [non-deuterated]) of -0.021 (* 0.001) for benzene, -0.028 (rt 0.002) for toluene, and -0.035 (rt 0.003) for ethylbenzene. The small values of A log Kcc demonstrates that deuterated compounds am excellent tracers for the hydrologic behavior of ground water contaminants. 01997
A detailed stable isotope (S, 0) and elemental (major, trace, S content) study of peraluminous S-... more A detailed stable isotope (S, 0) and elemental (major, trace, S content) study of peraluminous S-type granites and granodiorites of the South Mountain Batholith and the Meguma Group metasediments into which the batholith was intruded has been conducted on a regional and local scale near Mt. Uniacke. Sulfur contents of the metasediments range from 5 to 2440 ppm, and 634S ranges from -3.7 to +26.3%0. Sulfur contents of the igneous rocks range from 6 to 570 ppm, with the granites ( -20 ppm) having lower sulfur contents than the granodiorites ( =300 ppm) . Approximately 30 to 60% of the sulfur in the granodiorites is present as pyrrhotite (a late phase), with most of the remainder being present as sulfur substituted into biotite (an early phase). 6 "OouaRz values of the Mt. Uniacke granodiorites are heavy ( = + 12.2%0) indicating formation of the magmas by partial melting of sedimentary rocks. Major element variations suggest that the granites are related to the granodiorites by fractional crystallization of plagioclase, quartz, and biotite. Comparison of the sulfur contents of the granodiorites with experimental determinations of sulfur solubility suggest that the distribution coefficient of sulfur (Ds) between the cumulate and the magma during fractional crystallization -4. The regional granodiorites have a relatively restricted range of 634S values (+5.4 to f&4%0), while the regional granites have a wide range of 634S values (+1.6 to + 15.0%0). Granodiorites at Mt. Uniacke with normal magmatic values ( $0.76 to + 1.42%0) for A "0 (Quartz-Feldspar) have 634S values between +6.6 and + 12.3%0, and show good negative correlations between 6 34S and S, FeO, and MgO contents, Some granodiorites at Mt. Uniacke have anomalously low sulfur contents for their major element composition, and A '*O (Quartz-Feldspar) values (-0.45 to +0.67%0) indicate that these samples have undergone hydrothermal alteration, and this alteration event is probably responsible for the low sulfur contents.
Permanganate oxidation of chlorinated ethylenes is an attractive technique to effect remediation ... more Permanganate oxidation of chlorinated ethylenes is an attractive technique to effect remediation of these important groundwater contaminants. Stable carbon isotope fractionation associated with permanganate oxidation of trichloroethylene (TCE), tetrachloroethylene (PCE), and cis-1,2-dichloroethylene (cDCE) has been measured, to study the possibility of applying stable carbon isotope analysis as a technique to assess the efficacy of remediation implemented by permanganate oxidation. Average carbon isotope fractionation factors of R TCE ) 0.9786, R PCE ) 0.9830, and R cDCE ) 0.9789 were obtained, although the fractionation factor for PCE may be interpreted to change from a value of 0.9779-0.9871 during the course of the reaction. The fractionation factors for all three compounds are quite similar, in contrast to the variation of fractionation factors vs degree of chlorination observed for other degradative processes, such as microbial dechlorination. This may be due to a common rate-determining step for permanganate oxidation of all three compounds studied. The large fractionation factors and the relative lack of dependence of the fractionation factors upon other environmental factors (e.g. oxidation rate, presence of multiple contaminants, incomplete oxidation, presence of chloride in solution) indicate that monitoring δ 13 C values of chlorinated ethylenes during oxidation with permanganate may be a sensitive, and potentially quantitative, technique to investigate the extent of degradation.
... If Mn concentration is indeed a proxy for alteration by fresh water, a plot of δ 18 O vs. ...... more ... If Mn concentration is indeed a proxy for alteration by fresh water, a plot of δ 18 O vs. ... Dickson,JAD, 1990, Carbonate mineralogy and chemistry, in Tucker, ME, and Wright, VP, eds.,Carbonate sedimentology: Boston, Blackwell Scientific, p. 284313. ...
Contributions to Mineralogy and Petrology, Jan 1, 1989
Page 1. Contrib Mineral Petrol (1989) 101:418425 Contributions to Mineralogy and Petrology 9 Spri... more Page 1. Contrib Mineral Petrol (1989) 101:418425 Contributions to Mineralogy and Petrology 9 Springer-Verlag 1989 Devolatilization equilibria in graphite-pyrite-pyrrhotite bearing pelites with application to magma-pelite interaction ...
... Biochemistry 5:467-477. Page 9. Metal Toxicity to D. desulfuricans 49 Hammack, RW, and Edenbo... more ... Biochemistry 5:467-477. Page 9. Metal Toxicity to D. desulfuricans 49 Hammack, RW, and Edenbom, HM 1992. The removal of nickel from mine waters using bacte-rial sulfate reduction. Appl. Microbiol. Biotechnol. 37:674-678. ...
The solubility of toluene has been measured in distilled water, and in various inorganic salt sol... more The solubility of toluene has been measured in distilled water, and in various inorganic salt solutions. Values of the Setschenow constant, K(S), which quantify toluene solubility versus salt concentration, have been determined for each salt. Values of K(S) are compared to the activity of water for the salt solutions. Data from this study, consistent with earlier data, suggests that the effects of salts upon toluene solubility are non-additive. This contrasts the additive behavior of inorganic salts upon the solubility of nonpolar organic compounds, such as benzene and naphthalene, reported in the literature. Specific interaction between slightly polar toluene and ions in solution is suggested as a possible explanation for the non-additive effect of salts on the solubility of toluene.
Previous work on adsorption of oxalate at aluminosilicate surfaces suggests that maximum adsorpti... more Previous work on adsorption of oxalate at aluminosilicate surfaces suggests that maximum adsorption occurs through a bidentate attachment of the organic ligand, at nearneutral pH. Rates of ligand-promoted dissolution are expected to be greatest at this pH as well. We tested this model by measuring oxalate adsorption on the surface of andesine (An 47 ), in solutions of pH 3-5 and total oxalate concentrations of 0-8 mM. Contrary to expectation, the greatest adsorption density of 24 µmol m -2 total oxalate was observed at pH 3 and 8 mM total oxalate. Adsorption is dependent upon the activities of both oxalate (C 2 O 4 2-) and bioxalate (HC 2 O 4 -) in solution and can be modeled with either a two-term Langmuir or a two-term Freundlich isotherm. A Freundlich adsorption model provided the best fit to rate data because it was not constrained to a finite number of adsorption sites, as was the Langmuir model. The two-term ligand adsorption model was incorporated into a rate model:
Sorption partition coeffkients between water and organic carbon (K,) for deuterated benzene, tolu... more Sorption partition coeffkients between water and organic carbon (K,) for deuterated benzene, toluene, and etttylkmz.ene have been estimated by measuring values of the octanol-water partition coefficient (Kc,,) and HPLC retention factors (k'), which correlate closely to values of Kcc. Measured values of log Kc,, for nondeuterated and de&rated toluene are 2.77 (i 0.02) and 2.78 (It O&t), respectively, indicating that within ,experimental error, log Kc, for deuterated and nondeuterated toluene are the same. The HPLC method provides greater precision, and yields values of A log Kcc (= log Kcc [deuterated] -log Kcc [non-deuterated]) of -0.021 (* 0.001) for benzene, -0.028 (rt 0.002) for toluene, and -0.035 (rt 0.003) for ethylbenzene. The small values of A log Kcc demonstrates that deuterated compounds am excellent tracers for the hydrologic behavior of ground water contaminants. 01997
This study investigates the carbon isotope systematics of benzene, toluene, ethylbenzene, and xyl... more This study investigates the carbon isotope systematics of benzene, toluene, ethylbenzene, and xylene monoaromatic hydrocarbons (BTEX) with regard to an improved understanding of the behavior of these compounds in the subsurface, particularly during remediation processes. We found that fractionation eects due to vaporization are small and positive for all compounds studied (D 13 C vapor±liquid Q+0.2-), and that fractionation eects due to soil adsorption are also likely to be small ( 13 C-labeled compounds cannot be resolved from unlabeled compounds by HPLC). We also evaluated use of the isotopic composition of contaminants as tracers of source and migration in the subsurface by performing a survey of the bulk isotopic composition of commercially available sources of BTEX. The results indicate that a wide range of d 13 C values exist (e.g., benzene, À23.87-to À29.40-). Our work suggests that stable C isotope analysis has great potential for qualifying, and possibly quantifying, the subsurface processes aecting contaminant concentrations. In particular, stable isotope analysis may be especially bene®cial for monitoring the ecacy of abiological and biological remediation eorts. #
Page 142. Chapter 10 x Pore Fluid Chemistry of a Pressure Seal Zone, Moore-SamsMorganza Gas Fiel... more Page 142. Chapter 10 x Pore Fluid Chemistry of a Pressure Seal Zone, Moore-SamsMorganza Gas Field, Tuscaloosa Trend, Louisiana Thomas P. Ross Arthur W. Rose Simon R. Poulson Pennsylvania State University University ...
Unlike the majority of the water in the flooded mine complex of Butte Montana, which includes the... more Unlike the majority of the water in the flooded mine complex of Butte Montana, which includes the highly acidic Berkeley pit lake, groundwater in the flooded West Camp underground mine workings has a circum-neutral pH and contains at least 8 mM aqueous sulfide. This article examines the geochemistry and stable isotope composition of this unusual H 2 S-rich mine water, and also discusses problems related to the colorimetric analysis of sulfide in waters that contain FeS (aq) cluster compounds. The West Camp mine pool is maintained at a constant elevation by continuous pumping, with discharge water that contains elevated Mn (90 mM), Fe (16 mM), and As (1.3 mM) but otherwise low metal concentrations. Dissolved inorganic carbon in the mine water is in chemical and isotopic equilibrium with rhodochrosite in the mineralized veins. The mine water is under-saturated with mackinawite and amorphous FeS, but is supersaturated with Cu-and Zn-sulfides. However, voltammetry studies show that much of the dissolved sulfide and ferrous iron are present as FeS (aq) cluster molecules: as a result, the free H 2 S + HS À concentration of the West Camp water is poorly constrained. Concentrations of dissolved sulfide determined by colorimetry were lower than gravimetric assays obtained by AgNO 3 addition, implying that the FeS (aq) clusters are not completely extracted by the Methylene Blue reagent. In contrast, the clusters are quantitatively extracted as Ag 2 S after addition of AgNO 3 . Isotopic analysis of co-existing aqueous sulfide and sulfate confirms that the sulfide was produced by sulfate-reducing bacteria (SRB). The H 2 S-rich mine water is not confined to the immediate vicinity of the extraction well, but is also present in flooded mine shafts up to 3 km away, and in samples bailed from mine shafts at depths up to 300 m below static water level. This illustrates that SRB are well established throughout the southwestern portion of the extensive (>15 km 3 ) Butte flooded mine complex.
Oxygen isotope analyses of water, and carbon isotope analyses of dissolved inorganic carbon (DIC)... more Oxygen isotope analyses of water, and carbon isotope analyses of dissolved inorganic carbon (DIC), CO*(g), and CHh(@ have been performed on samples from normal and overpressured horizons in the Louisiana Gulf Coast. S OsMow values of the waters range from -2.2 to + 8.7%. Consideration of the aI80 values, the chemical composition of the waters, and the water and gas production values indicate that mixing with a low salinity, isotopically light water has taken place. Mixing lines suggest that the isotopically light component may be water vapor condensed during gas production, with a Rayleigh fractionation process accompanying vapor condensation, rather than shallow groundwater. Mixing lines suggest that all formation waters have 6"O x + 8%0, which is normal for deep, basinal waters, although Cl-concentrations indicate there are 2 water populations (with approximately 35,000 mg/l and 15,000 to 20,000 mg/l). There appears to be no systematic difference between the overpressured and normally pressured samples, or between samples from different fields. 613C Pea values of DIC range from -10.6 to -3.2%. G'3Cp~s values of CH4 range from -43.9 to -40.8%,,, and 613C ~,,a values of CO2 range from -8.8 to -6.3L, indicating that these gases have a thermogenic origin. Significant isotopic differences are observed between the Moore-Sams and Morganza samples which suggest that the Morganza gases were produced at higher temperatures and/or by the decomposition of more mature source material. The CO* and DIC are not in isotopic equilibrium with calcite and dolomite cements immediately above and below the seal, suggesting that precipitation of calcite and dolomite took place in an earlier event(s). The DIC of most samples is at, or near, isotopic equilibrium with COz, although it appears that some samples have derived a significant component of DIC from isotopically heavier samples located both higher and lower in the section. The lack of isotopic equilibrium between DIC and CO> for some samples suggests either that some water samples have little or no contact with coexisting gas samples, or that a dynamic process is taking place that prevents equilibrium being achieved.
The oxygen isotope fractionation between NaCO~-and water in the presence of NaC1 concentrations u... more The oxygen isotope fractionation between NaCO~-and water in the presence of NaC1 concentrations up to 4 M at temperatures between 100 ° and 300 °C has been investigated using a new, high-temperature titration technique. Dissolved carbonate is equilibrated at temperature with the experimental solution, and then the carbonate is quantitatively precipitated as BaCO3 by the injection of BaC12 solution at temperature. The isotopic composition of the BaCO3 reflects the composition of the free water, and hence reflects changes in the oxygen isotope composition of the free water due to the presence of NaC1. Under the experimental conditions used in this study, NaCO3-is the dominant dissolved carbonate species, and the oxygen isotope fractionation between NaCO~-and water between 100 ° and 300°C is given by: 1000 In ~=2.7( 106T-2)-5.7
PDF Click to view page images in PDF format. Volume: 80 ( 1996 ). Issue: 7. (July). First Page: 1... more PDF Click to view page images in PDF format. Volume: 80 ( 1996 ). Issue: 7. (July). First Page: 1045. Last Page: 1063. Title: Diagenesis, Compaction, and Fluid Chemistry Modeling of a Sandstone Near a Pressure Seal: Lower Tuscaloosa Formation, Gulf Coast. ...
Previous work on adsorption of oxalate at aluminosilicate surfaces suggests that maximum adsorpti... more Previous work on adsorption of oxalate at aluminosilicate surfaces suggests that maximum adsorption occurs through a bidentate attachment of the organic ligand, at nearneutral pH. Rates of ligand-promoted dissolution are expected to be greatest at this pH as well. We tested this model by measuring oxalate adsorption on the surface of andesine (An 47 ), in solutions of pH 3-5 and total oxalate concentrations of 0-8 mM. Contrary to expectation, the greatest adsorption density of 24 µmol m -2 total oxalate was observed at pH 3 and 8 mM total oxalate. Adsorption is dependent upon the activities of both oxalate (C 2 O 4 2-) and bioxalate (HC 2 O 4 -) in solution and can be modeled with either a two-term Langmuir or a two-term Freundlich isotherm. A Freundlich adsorption model provided the best fit to rate data because it was not constrained to a finite number of adsorption sites, as was the Langmuir model. The two-term ligand adsorption model was incorporated into a rate model:
Many rivers undergo diel (24-h) concentration fluctuations of pH, dissolved gases, trace metals, ... more Many rivers undergo diel (24-h) concentration fluctuations of pH, dissolved gases, trace metals, nutrients, and other chemical species. A study conducted in 1994 documented such behavior in the upper Clark Fork River, Montana, a stream whose headwaters have been severely ...
... 2SO 4 2− + 16H + (3)Fe 3+ + H 2 O + hυ → Fe 2+ + H + + OH Unlike Fe(II) oxidation, oxidation ... more ... 2SO 4 2− + 16H + (3)Fe 3+ + H 2 O + hυ → Fe 2+ + H + + OH Unlike Fe(II) oxidation, oxidation of pyrite by Fe 3+ is rapid at low pH and will take place in the presence or absence of bacteria ( [Garrels and Thompson, 1960] , [Singer and Stumm, 1970] , [Williamson and Rimstidt ...
Sorption partition coeffkients between water and organic carbon (K,) for deuterated benzene, tolu... more Sorption partition coeffkients between water and organic carbon (K,) for deuterated benzene, toluene, and etttylkmz.ene have been estimated by measuring values of the octanol-water partition coefficient (Kc,,) and HPLC retention factors (k'), which correlate closely to values of Kcc. Measured values of log Kc,, for nondeuterated and de&rated toluene are 2.77 (i 0.02) and 2.78 (It O&t), respectively, indicating that within ,experimental error, log Kc, for deuterated and nondeuterated toluene are the same. The HPLC method provides greater precision, and yields values of A log Kcc (= log Kcc [deuterated] -log Kcc [non-deuterated]) of -0.021 (* 0.001) for benzene, -0.028 (rt 0.002) for toluene, and -0.035 (rt 0.003) for ethylbenzene. The small values of A log Kcc demonstrates that deuterated compounds am excellent tracers for the hydrologic behavior of ground water contaminants. 01997
A detailed stable isotope (S, 0) and elemental (major, trace, S content) study of peraluminous S-... more A detailed stable isotope (S, 0) and elemental (major, trace, S content) study of peraluminous S-type granites and granodiorites of the South Mountain Batholith and the Meguma Group metasediments into which the batholith was intruded has been conducted on a regional and local scale near Mt. Uniacke. Sulfur contents of the metasediments range from 5 to 2440 ppm, and 634S ranges from -3.7 to +26.3%0. Sulfur contents of the igneous rocks range from 6 to 570 ppm, with the granites ( -20 ppm) having lower sulfur contents than the granodiorites ( =300 ppm) . Approximately 30 to 60% of the sulfur in the granodiorites is present as pyrrhotite (a late phase), with most of the remainder being present as sulfur substituted into biotite (an early phase). 6 "OouaRz values of the Mt. Uniacke granodiorites are heavy ( = + 12.2%0) indicating formation of the magmas by partial melting of sedimentary rocks. Major element variations suggest that the granites are related to the granodiorites by fractional crystallization of plagioclase, quartz, and biotite. Comparison of the sulfur contents of the granodiorites with experimental determinations of sulfur solubility suggest that the distribution coefficient of sulfur (Ds) between the cumulate and the magma during fractional crystallization -4. The regional granodiorites have a relatively restricted range of 634S values (+5.4 to f&4%0), while the regional granites have a wide range of 634S values (+1.6 to + 15.0%0). Granodiorites at Mt. Uniacke with normal magmatic values ( $0.76 to + 1.42%0) for A "0 (Quartz-Feldspar) have 634S values between +6.6 and + 12.3%0, and show good negative correlations between 6 34S and S, FeO, and MgO contents, Some granodiorites at Mt. Uniacke have anomalously low sulfur contents for their major element composition, and A '*O (Quartz-Feldspar) values (-0.45 to +0.67%0) indicate that these samples have undergone hydrothermal alteration, and this alteration event is probably responsible for the low sulfur contents.
Permanganate oxidation of chlorinated ethylenes is an attractive technique to effect remediation ... more Permanganate oxidation of chlorinated ethylenes is an attractive technique to effect remediation of these important groundwater contaminants. Stable carbon isotope fractionation associated with permanganate oxidation of trichloroethylene (TCE), tetrachloroethylene (PCE), and cis-1,2-dichloroethylene (cDCE) has been measured, to study the possibility of applying stable carbon isotope analysis as a technique to assess the efficacy of remediation implemented by permanganate oxidation. Average carbon isotope fractionation factors of R TCE ) 0.9786, R PCE ) 0.9830, and R cDCE ) 0.9789 were obtained, although the fractionation factor for PCE may be interpreted to change from a value of 0.9779-0.9871 during the course of the reaction. The fractionation factors for all three compounds are quite similar, in contrast to the variation of fractionation factors vs degree of chlorination observed for other degradative processes, such as microbial dechlorination. This may be due to a common rate-determining step for permanganate oxidation of all three compounds studied. The large fractionation factors and the relative lack of dependence of the fractionation factors upon other environmental factors (e.g. oxidation rate, presence of multiple contaminants, incomplete oxidation, presence of chloride in solution) indicate that monitoring δ 13 C values of chlorinated ethylenes during oxidation with permanganate may be a sensitive, and potentially quantitative, technique to investigate the extent of degradation.
... If Mn concentration is indeed a proxy for alteration by fresh water, a plot of δ 18 O vs. ...... more ... If Mn concentration is indeed a proxy for alteration by fresh water, a plot of δ 18 O vs. ... Dickson,JAD, 1990, Carbonate mineralogy and chemistry, in Tucker, ME, and Wright, VP, eds.,Carbonate sedimentology: Boston, Blackwell Scientific, p. 284313. ...
Contributions to Mineralogy and Petrology, Jan 1, 1989
Page 1. Contrib Mineral Petrol (1989) 101:418425 Contributions to Mineralogy and Petrology 9 Spri... more Page 1. Contrib Mineral Petrol (1989) 101:418425 Contributions to Mineralogy and Petrology 9 Springer-Verlag 1989 Devolatilization equilibria in graphite-pyrite-pyrrhotite bearing pelites with application to magma-pelite interaction ...
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