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Craig, H, Weiss RF, Clarke WB.  1967.  Dissolved gases in Equatorial and South Pacific Ocean. Journal of Geophysical Research. 72:6165-&.   10.1029/JZ072i024p06165   AbstractWebsite

The nitrogen, oxygen, and argon in Pacific samples from two expeditions have been measured by gas chromatography, and the neon and helium by mass spectrometry. Nitrogen is systematically about 2% supersaturated and argon about 1.5% undersaturated, relative to the solubility data of Douglas for a moisture saturated atmosphere at 1013-mb total pressure. N2/Ar ratios are in precise agreement with the solubility ratios of Benson and Parker. The range and covariance of N2 and Ar variations are consistent with atmospheric pressure variations over the sea. Oxygen values are systematically higher than the ‘classical’ Winkler values by 3.7%. No evidence was found for the large supersaturation of argon reported by Bieri, Koide, and Goldberg in 1966 and the Ar-T-S relationships are inconsistent with their vertical mixing model. Small increases in a saturation anomaly are core properties of water types formed by subsurface mixing and are associated with T-S slope changes; these effects were found in Antarctic and North Pacific Intermediate water. An upper limit of 8.7% excess helium was found at a depth of 1000 meters at 33°S latitude.

Craig, H, Weiss RF.  1968.  Argon concentrations in the ocean: A discussion. Earth and Planetary Science Letters. 5:175-&.   10.1016/s0012-821x(68)80036-6   AbstractWebsite

Because of the importance of argon as a conservative gas tracer in the oceans and as the only rare gas measured both by mass spectrometry and gas chromatography, critical evaluation and comparison of data measured by the two methods is essential. The use of isotope dilution methods in the mass-spectrometric analyses has produced essentially identical precision and accuracy as have been obtained by gas chromatography and the latest Pacific data are in good agreement, especially below 1000 meters depth. The recent data of Bieri et al. provide significant new evidence for the processes we have proposed as responsible for extrema in the saturation anomalies. The data are also consistent with calculations of diffusional losses of the rare gases in northward flowing bottom water in the Pacific.

Weiss, RF.  1968.  Piggyback sampler for dissolved gas studies on sealed water samples. Deep-Sea Research. 15:695-699.   10.1016/0011-7471(68)90082-x   AbstractWebsite

A sampler which obtains leak-proof sealed water samples from any depth has been developed for the study of dissolved gases. Closing of the sampler is activated by the tripping of the Nansen bottle to which it is attached. The water collected by the sampler is thus taken at the same time and place at which the Nansen bottle measures thermometric depth and temperature and collects water for measurement of salinity and other properties. Other advantages include ease of operation and low cost. The sampler has been tested at sea under a wide range of conditions.

Weiss, RF.  1969.  Dissolved argon, nitrogen and total carbonate in the Red Sea brines. Hot brines and recent heavy metal deposits in the Red Sea; a geochemical and geophysical account. ( Degens ET, Ross DA, Eds.).:254-260., New York: Springer-Verlag Abstract
Takahashi, T, Weiss RF, Culberson CH, Edmond JM, Hammond DE, Wong CS, Li Y-hui, Bainbridge AE.  1970.  A carbonate chemistry profile at the 1969 GEOSECS intercalibration station in the eastern Pacific Ocean. Journal of Geophysical Research. 75:7648-7666., Washington, DC, United States (USA): American Geophysical Union, Washington, DC   10.1029/JC075i036p07648   AbstractWebsite

To compare and evaluate measurements made by the various laboratories participating in the Geochemical Ocean Section Study (Geosecs), four carbonate chemistry parameters, pH, pCO2, alkalinity, and total dissolved CO2, as well as temperature and salinity were measured for samples collected at the Geosecs intercalibration station, 28°20′±07′N and 121°41′±02′W. The methods for measurement include the glass-calomel electrode pair for pH, the pH and the potentiometric acid titration methods for alkalinity, gas chromatographic, infrared and potentiometric acid titration method for total CO2, and the gas equilibrator-infrared method for pCO2. The alkalinity values measured by the pH method agree with the values measured by the potentiometric acid titration method within 1%, and the total CO2 values measured by the chromatographic method agree with the values measured by the potentiometric acid titration method within 2%. The observed 3 to 5% difference between the total CO2 values measured by the chromatographic and infrared methods is attributed to the biological alteration of the unpoisoned samples used for the infrared methods. When two of the four measured carbonate parameters were used to calculate the remaining two parameters, the calculated values are found to differ systematically from the measured values for those two parameters. Such a discrepancy can be eliminated if a 30% error in the second apparent dissociation constant for carbonic acid (K2′) is assumed.

Craig, H, Weiss RF.  1970.  The GEOSECS 1969 Intercalibration Station: Introduction, hydrographic features, and total CO2-O2 relationships. Journal of Geophysical Research. 75:7641-7647., Washington, DC, United States (USA): American Geophysical Union, Washington, DC   10.1029/JC075i036p07641   AbstractWebsite

The temperature, salinity, dissolved oxygen, and shipboard chromatograph ΣCO2 data from the 1969 Geosecs station are summarized. Vertical diffusion-advection model parameters calculated from the ΣCO2 and O2 data, by using the mixing parameters obtained from temperature and salinity, give approximately equal mean CO2 production and O2 consumption rates over the deep-water column.

Weiss, RF.  1970.  Helium isotope effect in solution in water and seawater. Science. 168:247-248.   10.1126/science.168.3928.247   AbstractWebsite

The isotope effect in the solution of helium in water from 0° to 40°C has been determined by microgasometric measurements of the solubilities of pure helium-3 and helium4. At 0°C helium-3 is less soluble than helium-4 in both distilled water and sea-water by 1.2 percent. The observed fractionation factor is 0.988±0.002 at 0°C and appears to decrease with increasing temperature at the rate of 0.0001 per degree Centigrade, although the existence of this trend is of limited statistical certainty. The measured isotope effect is in agreement with the ratio of helium-3 to helium-4 in surface ocean water reported by Clarke, Beg, and Craig.

Weiss, RF.  1970.  The solubility of nitrogen, oxygen and argon in water and seawater. Deep-Sea Research. 17:721-735.   10.1016/0011-7471(70)90037-9   AbstractWebsite

Recent precise data on the solubilities of nitrogen, oxygen and argon in distilled water and seawater are fitted to thermodynamically consistent equations by the method of least squares. The temperature dependence of the Bunsen solubility coefficient is treated using the integrated van't Hoff equation. It is shown that the Setchénow relation gives an adequate representation of the salting-out effect. Equations expressing the solubilities of these gases, as a function of temperature and salinity, in units of the Bunsen coefficient, ml/l., and ml/kg are given along with solubility tables in each of these units.

Craig, H, Weiss RF.  1971.  Dissolved gas saturation anomalies and excess helium in the ocean. Earth and Planetary Science Letters. 10:289-296.   10.1016/0012-821x(71)90033-1   AbstractWebsite

New solubility measurements have been made for helium and neon in seawater; the results (published elsewhere) show that neon is actually supersaturated in the ocean, rather than generally undersaturated as indicated by previous data. The pattern of He-Ne-Ar saturation anomalies, based on the new solubility data, shows the presence of an injected “atmospheric component” in Atlantic surface and deep waters and in Pacific deep waters, ranging from 0.5 to 1 ml of air (STP)/kg seawater. Nitrogen-argon relationships in the deep Pacific are also consistent with this effect. In addition to T and P, a third parameter is thus required for the study of saturation anomalies. The magnitude of the injected air fraction accounts for all of the “excess He” in Atlantic Deep Water and about 60% of the excess in the Pacific. The non-atmospheric excess He in the Pacific corresponds to an anomaly of 3%, presumably radiogenic and primordial helium.

Weiss, RF.  1971.  The effect of salinity on the solubility of argon in seawater. Deep-Sea Research. 18:225-230.   10.1016/0011-7471(71)90111-2   AbstractWebsite

New argon solubility measurements, made by two independent methods, confirm the use of the Setchénow relation in representing the salting-out of argon in seawater. No substantiation was found for the unusual salinity dependence implied by the argon solubility data of Murray and Riley (1970).

Weiss, RF.  1971.  Flushing characteristics of oceanographic sampling bottles. Deep-Sea Research. 18:653-656.   10.1016/0011-7471(71)90132-x   AbstractWebsite

The flushing characteristics of several types of oceanographic sampling bottles have been measured in a series of shipboard experiments using fluorescein dye. The results are consistent with a first-order model which may be used to calculate the flushing rate of a sampling bottle directly from its dimensions.

Weiss, RF.  1971.  Solubility of helium and neon in water and seawater. Journal of Chemical and Engineering Data. 16:235-241.   10.1021/je60049a019   AbstractWebsite

Sulfur hexafluoride (SF6) has been measured at Cape Grim since 1978 via a combination of in situ and flask measurements, including measurements on the Cape Grim air archive. The long-term growth rate of SF6 as observed at Cape Grim has increased from 0.1 ppt yr-1 in the late 1970s to 0.24 ppt yr-1 in the mid-1990s. Since then the growth rate has remained relatively constant at 0.23±0.02 ppt yr-1, indicating relatively constant global emissions (±10 %) since 1995. Pollution episodes at Cape Grim have been used to estimate regional (Melbourne and environs) and Australian emissions of SF6 at 3±1.5 and 15±7.5 tonnes yr-1 during 2001-2003.

Weiss, RF, Bucher P, Craig H, Oeschger H.  1972.  Compositional variations of gases in temperate glaciers. Earth and Planetary Science Letters. 16:178-&.   10.1016/0012-821x(72)90186-0   AbstractWebsite

Concentrations of N2, O2, Ar and CO2 in ice from the Aletsch Glacier in the Bernese Alps have been measured by gas chromatography. Newly formed ice at the head of the glacier contains N2, O2 and Ar in roughly atmospheric proportions, whereas the CO2 content is ∼ 50 times greater than in air. Samples from the terminus of the glacier are considerably lower in total gas content, and are depleted in Ar and O2 and enriched in N2 with respect to air. The CO2 of this gas is ∼ 100 times greater than in air. Model calculations show that the N2-O2-Ar relationships are explained by the removal of these gases in solution in meltwater. In the case of CO2, the results indicate that only a small fraction of the CO2 in the ice is present in bubbles, the remainder being distributed within the ice matrix. Adsorption of atmospheric CO2 probably plays a role in determining the concentrations and distribution of CO2 in glacier ice.

Kroopnic.P, Weiss RF, Craig H.  1972.  Total CO2,13C, and dissolved oxygen -18O at GEOSECS II in the North Atlantic. Earth and Planetary Science Letters. 16:103-110.   10.1016/0012-821x(72)90242-7   AbstractWebsite

This paper presents profiles of ΣCO2, δ13C in ΣCO2, dissolved O2, and δ18O in dissolved O2, measured at Geosecs II in the North Atlantic. The O2 minimum at 1000 m is accompanied by a minimum in δ13C and a sharp maximum in δ18O; ΣCO2 increases downward through this layer with a slope change. All four parameters are remarkably uniform in the deep and bottom water below the O2 minimum, almost to the precision of measurement. Relative to data previously reported from this area of the Atlantic, our ΣCO2 values are 3% lower than those of Li et al. [10], and our δ13C values are up to 2‰ greater than those of Deuser and Hunt [12]. Also, our δ18O enrichments in dissolved O2 are very much less than Pacific values reported by Dole and coworkers [15]. All of these differences are attributed principally to bacterial O2 consumption during sample storage by previous workers, due to lack of, or inadequate, poisoning.In contrast to the North Atlantic, there is a very large gradient of dissolved O2 in the vertical profile of North Pacific Deep Water; however, if themean deep-water O2 concentration is compared with the uniform value in North Atlantic Deep Water, the O2 and ΣCO2 differences in North Atlantic and North Pacific Deep Water are essentially equimolar at 160 μm/kg. If 77% of deep-water O2 consumption is used for oxidation of organic carbon (the R-K-R “model plankton” value), the increase in ΣCO2 in Pacific deep water is about 25% due to dissolution of carbonate, and 75% due to oxidation of organic matter, in the vertical particulate flux. These proportions are in agreement with those estimated from alkalinity-ΣCO2 variations [10]. Our δ13C measurements in the Atlantic are quite consistent with the ΣCO2-O2-alkalinity variations between the Atlantic and Pacific deep water; thus the disagreement previously noted [14] is attributed to storage effects on δ13C measurements by previous workers, as noted above.

Weiss, RF, Craig H.  1973.  Precise shipboard determination of dissolved nitrogen, oxygen, argon, and total inorganic carbon by gas chromatography. Deep-Sea Research. 20:291-303.   10.1016/0011-7471(73)90054-5   AbstractWebsite

A seagoing gas chromatographic system for the rapid and precise determination of dissolved gases in sea water is described. Separate instruments are employed for total inorganic carbon, and for nitrogen, oxygen, and argon analyses. Factors affecting the design, calibration, and shipboard operation of the system are discussed in detail. Results of intercomparisons with other analytical techniques confirm the accuracy of the gas chromatographic method. Profiles of ΣCO2, O2, and N2 measured aboard ship are presented and discussed.

Weiss, RF.  1974.  Carbon dioxide in water and seawater: the solubility of a non-ideal gas. Marine Chemistry. 2:203-215.   10.1016/0304-4203(74)90015-2   Abstract

New measurements of the solubility of carbon dioxide in water and seawater confirm the accuracy of the measurements of Murray and Riley, as opposed to those of Li and Tsui. Corrections for non-ideal behavior in the gas phase and for dissociation in distilled water are required to calculate solubility coefficients from these sets of data. Equations for the solubilities of real gases are presented and discussed. Solubility coefficients for carbon dioxide in water and seawater are calculated for the data of Murray and Riley, and are fitted to equations in temperature and salinity of the form used previously to fit the solubilities of other gases.

Krishnaswami, S, Lal D, Somayajulu BLK, Weiss RF, Craig H.  1976.  Large-volume in situ filtration of deep Pacific waters: mineralogical and radioisotope studies. Earth and Planetary Science Letters. 32:420-429.   10.1016/0012-821x(76)90082-0   AbstractWebsite

The concentrations of CaCO3 and radioisotopes,234Th,230Th,239Pu,226Ra and210Pb have been measured in particles of >1.2 μm collected from ∼4000 liters of Pacific waters (33°N−33°S; 124°W−170°E) at depths 700–5500 m. The mean “ash” concentrations are found to be 5 μg/kg seawater, about 3–4 times lower than that in the surface waters. The particulate concentrations (dpm/kg seawater) of239Pu shows a peak at 700–1000 m, whereas the particulate concentration of230Th and210Pb which are produced in-situ in seawater increases with depth. These results provide an insight into certain aspects of particle dynamics relevant to modification of trace element composition of seawater due to particle transport and sedimentation flux. The salient features of the results are:(1) The mean settling velocity of particles are in the range of (0.3−2) × 10−3 cm/sec corresponding to a sedimentation rate of 0.1−0.6 cm/103 yr.(2) The rate constant for the adsorption of Th on particles is deduced to be 8 × 10−8 sec−1 assuming a first-order scavenging model.

Weiss, RF, Craig H.  1976.  Production of atmospheric nitrous oxide by combustion. Geophysical Research Letters. 3:751-753.   10.1029/GL003i012p00751   AbstractWebsite

Measurements of N2O in the effluent gases from the burning of coal and fuel oil show that these are significant anthropogenic sources of atmospheric N2O. We estimate that the present global production of N2O from these sources is 1.6 Mtons N2O(N) per year and is increasing at a rate of ∼ 3.5% per year. Catalytic converters for the reduction of NO emissions also represent a major potential source of atmospheric N2O.

Chan, LH, Edmond JM, Stallard RF, Broecker WS, Chung YC, Weiss RF, Ku TL.  1976.  Radium and barium at Geosecs stations in Atlantic and Pacific. Earth and Planetary Science Letters. 32:258-267.   10.1016/0012-821x(76)90066-2   AbstractWebsite

Ra and Ba show a general linear correlation in the oceanic water column within the uncertainties of the data: the slope of the line is about 4.6 nanomoles (nmoles) Ra/mole Ba, the intercept being at about 4 nmoles Ba/kg. This demonstrates the usefulness of Ba as a “chemical analogue” of Ra. Box-model calculations indicate that the average deep-water excess of Ra over Ba should be about 10% relative to the surface. This is consistent with the observations outside the deep northeast Pacific. However, the uncertainties in the data are such that the regional variation in the primary input cannot be resolved. In the deep waters of the North Pacific there is in fact a large excess of Ra relative to Ba. The one detailed profile presently available (204) can be explained consistently by a simple vertical advection-diffusion model.

Weiss, RF.  1977.  Hydrothermal manganese in the deep sea: Scavenging residence time and Mn/3He relationships. Earth and Planetary Science Letters. 37:257-262.   10.1016/0012-821x(77)90171-6   AbstractWebsite

Measurements of hydrothermal Mn in the water column overlying the Galapagos Rift have been fitted to a one-dimensional first-order scavenging model. Assuming a vertical advection velocity of 4 m/yr, the model gives a scavenging residence time for Mn of 51 years. The horizontal propagation distance for hydrothermal Mn in the water column is thus estimated to be on the order of 1000 km. The Mg/3He injection ratios for the Galapagos Rift hydrothermal plume samples and the Red Sea brines are in close agreement. The Mn flux determined from the scavenging model and the estimates of Mn flux based on the Mg/3He injection ratio are compared to the Mn accumulation rates observed in deep-sea sediments.

Klinkhammer, G, Bender M, Weiss RF.  1977.  Hydrothermal manganese in the Galapagos Rift. Nature. 269:319-320.   10.1038/269319a0   AbstractWebsite

HYDROTHERMAL emanations originating at mid-ocean ridges have been thought1–5 to provide a substantial source of manganese to the ocean but the evidence supporting this hypothesis has been indirect. Anomalous manganese concentrations have been measured in naturally occurring systems where seawater is in direct contact with lava flows6–8. Laboratory studies have shown that seawater tends to leach manganese from basalts at elevated temperatures and pressures9–11. Anomalously high manganese accumulation rates have also been determined for sediments adjacent to active ridge systems, most notably the East Pacific Rise12–14. No measurements of manganese concentrations in seawater near mid-ocean ridges, or in hydrothermal fluids emanating from these ridges, have yet been made, however. We report here the results of the first such direct measurements, which show that manganese is being injected into the deep sea by hydrothermal circulation of seawater through newly-formed oceanic crust.

Weiss, RF, Lonsdale P, Lupton JE, Bainbridge AE, Craig H.  1977.  Hydrothermal plumes in the Galapagos Rift. Nature. 267:600-603.   10.1038/267600a0   AbstractWebsite

ALTHOUGH there is indirect evidence that a major fraction of the heat loss from newly-created lithosphere occurs by convection of seawater through the porous crust1–3, it has proved difficult to locate vents of deep-sea hydrothermal systems by direct measurement of the discharge fluid. Local increases in bottom water temperature up to 0.1 °C have been measured by towing arrays of thermistors a few metres above the axes of active oceanic spreading centres4,5, but these data are ambiguous because small temperature anomalies may have a hydrographic explanation. We report here the first conclusive measurements of modified seawater discharging as buoyant hydrothermal plumes from fissures in young oceanic crust. We obtained samples of hydrothermal plumes in the Galapagos Rift3, albeit after considerable dilution with surrounding bottom-water, and report the first results of the collection and analysis of these samples.

Imboden, DM, Weiss RF, Craig H, Michel RL, Goldman CR.  1977.  Lake Tahoe geochemical study .1. Lake chemistry and tritium mixing study. Limnology and Oceanography. 22:1039-1051. AbstractWebsite
Lupton, JE, Weiss RF, Craig H.  1977.  Mantle helium in hydrothermal plumes in the Galapagos Rift. Nature. 267:603-604.   10.1038/267603a0   AbstractWebsite

THE 3He/4He ratio in deep Pacific water is 20–30% higher than in atmospheric helium because of injection of primordial helium from the mantle1,2. The largest 3He enrichments in the Pacific have been found in water on the crest of the East Pacific Rise where the isotopic ratios indicate2 that the excess helium component has a 3He/4He ratio about ten times the atmospheric ratio, in agreement with the ratios measured in trapped helium in the glassy rims of oceanic tholeiites3,4. Recent measurements in this laboratory5 have shown that the hot brines in the axial rift of the Red Sea are very highly enriched in mantle helium. 3He and 4He are respectively 3300 and 380 times supersaturated relative to atmospheric solubility equilibrium in seawater, with a 3He/4He ratio of 1.2×10−5, or 8.6 times the ratio in atmospheric helium. Comparison of the enrichments of various elements in the Red Sea brines and in brines associated with salt domes6 shows that helium is the only component in the Red Sea brines which unequivocally requires derivation from hydrothermal circulation of seawater in basalts. The helium isotopes are thus an extremely powerful and sensitive tracer for the detection and mapping of hydrothermal systems in oceanic spreading centres.

Lupton, JE, Weiss RF, Craig H.  1977.  Mantle helium in the Red Sea brines. Nature. 266:244-246.   10.1038/266244a0   AbstractWebsite

HELIUM isotope studies on terrestrial samples have revealed the existence of two helium components which are clearly distinct from atmospheric helium. The first of these, which we term ‘crustal helium’, was identified in 1946 in natural gas wells1. This crustal component is produced by radioactive decay of U and Th to 4He, with 3He production by (n, α) reactions on Li; the resulting helium is characterised by 3He/4He ≃ 10−7, one-tenth of the atmospheric ratio2. The second component, ‘mantle helium’, was discovered as ‘excess 3He’ in deep ocean water, attributed to a flux of primordial helium from the mantle3. Studies of the 3He/4He ratio in deep water on the East Pacific Rise4 and in helium trapped in submarine basalt glasses5,6 have shown that this mantle component is characterised by 3He/4He ≃ 10−5, about 10 times the atmospheric ratio and 100 times the ratio in crustal helium. Basalt glasses from the Western Pacific Lau Basin, the East Pacific Rise, and the Mid-Atlantic Ridge contain trapped helium with similar 3He/4He ratios, indicating that mantle helium in at least three areas in which new lithosphere is being formed has a unique and uniform isotopic signature.