Rock/Mineral-Water Interaction |
| MAGMATIC TRITIUM A provocative paper in Nature proposing that "cold fusion" of deuterons inside the earth is partly responsible for the Earth's interior heat flow and (possibly) for Helium-3 anomalies observed in volcanic emissions. It was suggested that dD fusion in the Earth might cause tritium (Hydrogen-3) anomalies detectable in volcanic emissions. Although there has been much talk and research on the physics and chemistry of "cold fusion" since 1989, very little volcanological research has been conducted on the topic, other than speculation . Water is the dominant gas in most volcanic eruptions, thus determination of stable isotope (dD/dOxygen18) and Hydrogen-3 content of magmatic water is critical to our understanding of magmatic processes and conditions by which magma is generated in the crust or mantle. These isotopes are also necessary to evaluate interactions among magmatic waters, groundwaters, and precipitation. Until recently, published data on the stable isotopic composition of magmatic waters were not systematic and were confusing for at least three reasons. First, direct sampling of active volcanoes is often difficult and dangerous. Second, interactions between water types are difficult to resolve because boiling, evaporation, and high-temperature isotopic exchange produce a variety of isotopic fractionations and shifts. Third, isotopic analyses of volcanic rocks and their mineral constituents do not necessarily reflect the isotopic composition of the bulk of the water in parental melts, especially with respect to d. Furthermore, no systematic experiments except ours (described below) have been conducted on the Hydrogen-3 content of magmatic water because of the short half-life, the large H-bomb excess in the atmosphere, and the large samples (>300 ml) required to accurately analyze low-level 3H (<5 T.U. where 1 T.U. = 3.193 pCi/kg H2O). The few measurements previously made on the Hydrogen-3 content of steam from volcanic fumaroles are poorly constrained by other chemical and isotopic data and display large analytical variations. As a result, any Hydrogen-3 found in volcanic steam has been explained as meteoric contamination and prevailing wisdom has assumed that Hydrogen-3 (magma) is essentially 0. Our objectives are to measure anomalous Hydrogen-3 in magmatic water from active volcanoes, independent of magma composition or tectonic setting, and to evaluate if the Hydrogen-3 is an artifact of very shallow meteoric contamination or in-situ fission reactions. Because natural fusion (or "cold fusion" is a highly controversial subject, we have been told repeatedly by many outside critics that a variety of volcanoes must be investigated to demonstrate a universal phenomena. If magmatic Hydrogen-3 can be found in this spectrum of magma types and tectonic environments, we will have demonstrated that Hydrogen-3 production in the Earth is a viable concept worthy of other lines of research. Laboratory research in the U.S. on cold fusion has been unpopular due to difficulties in reproducing the results of earlier investigators and a variety of technical problems. The amount of energy released is apparently small. However, if direct evidence of anomalous Hydrogen-3 can be detected in the magmatic waters of several volcanoes of contrasting magma type and tectonic setting, it would lend strong support to the theory of natural fusion in the Earth and would require revisions in concepts on primordial Helium-3, mantle heat flow, and plate tectonics. Our work on magmatic Hydrogen-3 is one of the few projects related to cold fusion now conducted at Los Alamos. Our work, however, also requires us to collect many kinds of chemical and isotopic samples to characterize the magmatic nature of the fluids; thus we have developed methods and field portable equipment to obtain samples from extremely dangerous environments discharging acidic fluids at temperatures of 900 C. This methodology has applications to the transport of metals and creation of volcanic-hosted ore deposits and applications to the evolution of the atmosphere and changes in climate due to volcanic eruptions. Our approach requires direct sampling of active, high-temperature volcanic fumaroles and fresh lavas followed by analysis of a variety of chemical/isotopic parameters on the samples. Condensates from fumaroles are collected with titanium and/or pure silica glass tubes connected to a condenser. Our approach is unique because we collect large samples of condensed magmatic water from many fumaroles for Hydrogen-3 analysis (never done before) and because we use three isotopes of water (D, Hydrogen-3, and Oxygen-18) to eliminate effects of meteoric contamination or contamination by near-surface groundwaters. We also collect extensive background samples to compare with magmatic samples. The approach is demonstrated by our data set for Galeras volcano, Colombia which was obtained during a sampling campaign in Jan.-Feb. 1993 . Fumarole condensates have pH<1 and contain significant Cl, Br, F, B, and sulfur compounds of magmatic origin. The dD/dOxygen-18 relations (Figure 1) show the high-temperature condensates are isotopically enriched compared to all thermal and nonthermal groundwaters or rain. However, it can be seen that some meteoric water is mixed with magmatic water in even the highest-temperature fumaroles, a feature common to most volcanic fumaroles. The dOxygen-18 value of magma is obtained from the fresh lava bombs exploded out of Galeras crater (7.37%). Significantly, the same type of mixing relation between magmatic and meteoric waters is revealed in a plot of Hydrogen-3 vs. dOxygen-18 (Figure 1). High-temperature fumarole condensates have values different from all thermal and nonthermal groundwaters or rain. Extrapolation of the mixing trend to the dOxygen-18 value of magma yields a (statistical) Hydrogen-3 content of 0.00 0.03 T.U. Our Mount St. Helens, Kilauea, and Pacaya data sets (funded by earlier projects) show anomalous behavior and yield 3H values of 3.01 0.52, 2.97 0.15, and 0.76 0.05 T.U., respectively for their magmatic waters. Our results for Satsuma Iwo-Jima volcano are 0.0 T.U., similar to Galeras. Resampling of Mount St. Helens in June 1994 resulted in an apparent anomaly of 0.7 0.3 T.U. (data analysis is continuing). We have recently returned from the Galapagos islands, Ecuador (February 1995) where we sampled two more hot-spot volcanoes (Sierra Negra and Alcedo) but have no data as yet. We have been formally invited to sample Vulcano, a tracy-rhyolite volcano in Italy in May 1995. We would like to extend this work to a rift basalt volcano and a carbonatite volcano (both in Africa) in the future if at all possible. At this time, it is the P.I.'s opinion that the very small residual anomalies seen at some volcanoes are abberations caused by accumulated analytical errors, sampling errors, and extrapolation errors. This is a problem we will evaluate in detail toward the end of the project. In any event, the amount of "magmatic tritium" is very small, about 1 part in 1018 parts of magmatic water.
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