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1998 Academy Yearbook

The 1998 Academy Yearbook details the accomplishments of the Academy of the Royal Society of New Zealand throughout the year.

Werner Friedrich Giggenbach

Dr.rer.nat. FRSNZ

1937—1997

Werner Friedrich Giggenbach was born on 10 November 1937 in Augsburg (Germany). He studied chemistry at the Technical University of Munich (former Technische Hochschule Muenchen) and completed his study with the degree of Dr. rer.nat. in June 1966. His thesis (On the blue solutions of sulfur) was given the meritorious grade of ‘summa cum laude‘. Between September 1966 and August 1968 he undertook postdoctoral study at Michigan State University (US). In September 1968 he joined as ‘scientific officer’ the Chemistry Division of the Department of Scientific and Industrial Research (DSIR) in Lower Hutt. He became attached to a very active group under the leadership of Jim Ellis, involved in the study of geothermal and volcanic fluids. Werner remained almost 30 years with this group which upon the dissolution of the DSIR in 1992 became part of the Institute of Geological and Nuclear Sciences (IGNS). His New Zealand career was interrupted from March 1980 to October 1982 when he joined the International Atomic Energy Agency (IAEA) in Vienna and became project leader at their geothermal isotopic laboratory. Upon return, and after being promoted to ‘senior scientist’, he continued to widen his field of studies by looking at worldwide aspects of geothermal and volcanic fluid transfer processes using the opportunity of short-term consultancies for international aid projects to visit important geothermal and volcanic fields in all continents. He died on 7 Nov 1997 in Rabaul (Papua New Guinea) during an expedition to sample volcanic gases from the active Mt Tavurvur near Rabaul without knowing that in recognition of his scientific work he had been elected Fellow of the Royal Society of New Zealand.

Achievements

The above facts are an incomplete summary of the career of an outstanding New Zealand scientist who became an internationally recognised leader in the field of fluid and related fluid/rock interactions in active geothermal and volcanic systems. Werner also received international recognition for his work in affiliated disciplines such as mineral deposition associated with geothermal and volcanic systems, deep crustal fluid transport, and more recently for his studies of processes controlling the composition of carbon gases in sedimentary basins. Recognition of his work by the international scientific community is reflected, in part, by his numerous invitations to attend, as invited speaker, various prestigeous international conferences; he attended about 25 of these in this role during the last 10 years, including the 1992 Penrose Conference (US).

The development of his career can be seen by looking at his bibliography of about 100 refereed papers and chapters in books of which half are single author contributions (WFG) in leading geochemistry journals and conference proceedings. To this, one has to add his unpublished work which consists of numerous internal DSIR (Chemistry Division) and later IGNS reports, many unpublished reports for international agencies (UNDP, IAEA) and contributions to the NZ Geochemical Newsletter, the NZ Mineralogical Society Newsletter, and the NZ Volcanological Record series. Many of these contributions contain ideas which were developed much later as well researched scientific papers, thus indicating long gestation periods for some of his major work.

Although the output of an emminent scientist should not be assessed by the number of publications, Werner’s output is still impressive because at least half of his papers are very substantial pieces of work (covering usually 10 to 40 pages). That work has now been widely recognized overseas, it is read and developed further as indicated by the large number of citations given to his research, for example, in the International Science Citation Index. Werner is arguably the most widely cited New Zealand earth scientist overseas as the Index shows > 50 citations per year.

His scientific standing in New Zealand and overseas was also recognised by his many honours. The Geological Society of New Zealand awarded him the prestigious ‘MacKay Hammer’, the NZ Institute of Chemistry elected him as a fellow (FNZIC), as did the US Society of Economic Geologists. His professional judgement and knowledge were sought when he became an Associate Editor of the journals Applied Geochemistry (1986—1990) and the Bulletin of Volcanology (1991 to his death). He also was the Editor (since 1988) of the Newsletter of the IAVCEI Commission on Volcanic Gases. However, his last honour, the FRSNZ, was posthumous.

Traits, opportunties and the first half of his career

What were the traits which helped Werner to reach the top echelon? Most of us who knew him well agree that his honest and upright personal character, his inquisitive and critical mind, which allowed him to look beyond his own discipline, as well as his sound academic and research skills were such traits. As for his scientific honesty, most of us knew that Werner was obsessed with obtaining ‘perfect’ fluid analyses so he did not leave complex analyses to technical staff, but did the work himself until others could produce results with the same precision.There is no doubt that he was an excellent analyst himself and that this skill contributed to his later achievements.

However, there were also other important outside factors. At the start of his New Zealand career he was fortunate to join a group of very able and active young chemists who had been recruited by Jim Ellis (FRSNZ) to advance research in the complex field of geothermal fluids and fluid/rock interactions. This group and Jim Ellis’s work were already internationally known when Werner joined. When he was asked to collect representative fluid samples from New Zealand geothermal and volcanic fields with difficult access, he showed that he was also a good field scientist who learned quickly to sample even under trying conditions. His love and drive to understand the powerful discharges of volcanoes began in the early 1970s with his first sampling programme of active New Zealand volcanoes, a programme which he repeated in the years to come.

There were also other important circumstances which allowed Werner to move from the position of an established geochemist (in government service) to become a world leader in his field. To check whether preliminary findings from his New Zealand based geothermal/volcanological research programme also had wider implications, Werner had to leave the safe benches of his Lower Hutt laboratory, with the support from his supervisors, to sample other high temperature geothermal- and volcanic systems in the world using whatever opportunity there was to do so. The first opportunity came in 1973 to sample volcanic fluids in the crater of Mt Erebus (Antarctica); it took another three expeditions until Werner was happy with the quality of his samples. Short-term visits to geothermal prospects in developing countries were also used since the United Nations Development Programme (UNDP) needed short-term consultants for their geothermal programmes in several developing countries. A formal agreement between the New Zealand Government and UNDP for such assistance had been drawn up in 1967 and allowed numerous New Zealand earth scientists and engineers to gain overseas experience. Werner, as a fresh UNDP consultant, visited in the 1970s numerous geothermal fields in India, Chile, the Solomon Islands, Mexico, Thailand and Italy. During this decade he still found enough time in New Zealand to research the chemistry of sulfur species in high temperature liquids, to study the isotopic compositions of geothermal fluids, and to start with what became his main work, the evolution of fluids in geothermal systems. He had collected enough data to show that the compositions of geothermal gases and liquids are governed by thermodynamic equilibria (involving fluid / rock interactions) which can be predicted. This lead in 1980/81 to two of his most important publications (in Geochimica and Cosmochimica Acta) which also provide a convenient mid point of his career.

The second half

The second half of Werner’s professional life began in Vienna where he spent two years in the IAEA geothermal isotope laboratory. This brought him into contact with the best isotope laboratories in the world and allowed a study of rare natural, non-reactive isotopes, such as He, associated with deep subcrustal fluid transport. He enjoyed his time in Vienna, especially since he could continue with his ‘worldwide geothermal fluid sampling programme’ in Mexico and several other Central American countries. He also became interested in a poorly understood geothermal system which he called: ‘volcanic-magmatic-hydrothermal system’, a hydrothermal system which contains a core of magmatic fluids.

After his return from Vienna at the end of 1982, he maintained close contact with the IAEA group and was invited, as an expert, to attend most of their meetings in developing countries from 1984 onward. As consultant for UNESCO, UNDP, and IAEA he could complete his worldwide fluid sampling programme during the 1980s by visiting geothermal projects and volcanoes in Guatemala, Colombia, Ecuador, Costa Rica, and the Philippines. In Colombia he found, in the active volcano of Nevado del Ruiz, a classical example for his volcanic-magmatic-hydrothermal-system and predicted, although unrelated to his studies, the likely path of dangerous lahars should a volcanic eruption occur. The eruption of Ruiz three months later in November 1985 confirmed his prediction. He was now in demand by the International Volcanological Commission and was sent, together with other experts, to Cameroon in 1986 to investigate the cause of the ‘cold’ eruption of Lake Nyos where a cloud of carbon dioxide had suffocated almost 2000 people. His understanding of the anomalous 3He component in the gas allowed him to come up with the finding that the disaster had been caused by an accumulation of dissolved carbon dioxide entering the lake from great depths without volcanic processes. Most other experts had opted for some type of thermal eruption, but Werner got it right from the beginning. It was probably this success which made him famous among his peers.

In the meantime his main research became more focussed on the evolution of volcanic-magmatic fluids in hydrothermal systems and associated mineral deposition processes. His discovery (published in 1987), that redox processes govern the chemistry of fumarolic discharges which contain both a primary magmatic and a secondary hydrothermal component, was a major step towards partioning fluid/rock interactions for each component. A few years later, he formulated the conditions which allow the deposition of minerals in volcanic-magmatic-hydrothermal systems; it was probably this work for which he was rewarded with a fellowship by the US Society of Economic Geologists in 1991. Parallel to this were his studies of the isotopic and chemical composition of fluid discharges as a function of their plate tectonic setting which allowed him to distinguish clearly between the signatures of gases from cooling andesitic and rhyolitic plutons and which showed that geothermal and volcanic discharges of the Taupo Volcanic Zone in New Zealand were similar to those of other volcanic island arc settings. His research on the evolution of volcanic-magmatic fluids, associated mineral deposition processes, and the signatures of crustal and deep sub-crustal melts were combined when he wrote his treatise on: ‘The origin and evolution of fluids in magmatic-hydrothermal processes’ for the handbook of Geochemistry of Hydrothermal Ore Deposits which was published recently.

The legacy

Werner preferred to work alone and has no obvious scientific heir. However, his work was not done in seclusion and he enjoyed co-operation with other scientists as indicated by the multi — author papers in his publication list. He became involved in informal education when he found that many of his assistants and helpers in developing countries needed more education than his ‘hands-on’ training in the field provided. It is possible that he had this group in mind when he wrote ‘hands-on’ type of manuals dealing with ‘Geothermal Systems’ and ‘Chemical Techniques in Geothermal Exploration’ which were issued by IAEA (1983) and by UNITAR/UNDP (1991), respectively, and which are still read by graduates. He extended his ‘hands-on’ training to professionals when he organised the IAVCEI workshops in 1994 and 1997 dealing with proper collection and handling of volcanic gas samples.

He participated in formal education from 1980 onwards when he gave annually his ‘end of the term’ lectures to students from developing countries at the Geothermal Institute, University of Auckland. These could last up to a whole day and contained a clear synthesis of a wide range of geothermal topics. A similar group of students was taught when he gave lectures to the geothermal training course affiliated with the UN University in Iceland in 1995. Werner knew that most of these students had difficulty in understanding his complex thermodynamic derivations and he strived to condense them into the form of simple graphical, multi-parameter plots which would allow, for example, the assessment of cation equilibria of thermal fluids to predict important reservoir parameters. These mainly triangular graphs were presented to students in 1986, a few years before the method was described in a formal publication. Students have liked to use these plots ever since and refer to them as "Gigagrams". His name has also become attached to a small (0.2l litre) Pyrex bottle which he developed and which is now used all over the world for sampling geothermal and volcanic gases, the "Giggenbach Bottle". His work has recently inspired an international group of earth scientists to honour Werner’s legacy by compiling a special issue for the Journal of Volcanology and Geothermal Research.

When the second half of his professional life came to an end, Werner was at the peak of his career as a look at his annual publication rate shows. He was in a position to start to work on a book which would have provided a detailed account of his accumulated knowledge of mineral equilibria, chemical and isotopic composition of fluids in hydrothermal and hydrocarbon systems using a thermodynamic approach. The various chapters had already been outlined by Werner, co-authors had been identified, and a grant from the Marsden Fund had been awarded to undertake this work. Hopefully, this last document of Werner’s work can be completed by a group of invited scientists of international repute.

About 200 years ago the German poet Novalis described an explorer of the earth (In: Heinrich v.Ofterdingen, V), who could probe its depths, and who could forget all difficulties when he was close to nature. In the original language of Novalis (and Werner) the stanza reads:

Der ist der Herr der Erde,
wer ihre Tiefen misst,
und jeglicher Beschwerde
in ihrem Schoss vergisst.

Werner Giggenbach was such an explorer.

– Manfred P. Hochstein

Bibliography

  • 1968 (WFG and CH Brubaker Jr) Titanium(III)chloro complexes containing methanol, methoxide ion or acetonitrile. Inorganic Chemistry 7, 129—133.
  • 1968 (WFG) On the nature of the blue solutions of sulfur. J Inorg. Nucl. Chem. 30, 3189—3201.
  • 1969 (WFG and CH Brubaker Jr) The preparation and optical and electron spin resonance spectra of some chloro(methanol) complexes of Titanium(III). Inorganic Chemistry 8, 1131—1137.
  • 1970 (WFG) The blue solutions of sulfur in oleum. Chem.Commun., 852—853.
  • 1971 (AJ Ellis and WFG) Hydrogen sulphide ionization and sulphur hydrolysis in high temperature solution. Geochim. Cosmochim. Acta 35, 247—260.
  • 1971 (WFG) A simple spectrophotometric cell for use with aqueous solutions up to 280° C. J Phys. E, Scientific Instrum. 4, 148—149.
  • 1971 (WFG) The blue solutions of sulphur in water at elevated temperatures. Inorganic Chemistry 10, 1306—1308.
  • 1971 (WFG) The blue solutions of sulfur in salt melts. Inorganic Chemistry 10, 1306—1310.
  • 1971 (WFG) Optical spectra of highly alkaline sulfide solutions and the second dissociation constant of hydrogen sulfide. Inorganic Chemistry 10, 1333—1338.
  • 1971 (WFG) Isotopic composition of waters of the Broadlands geothermal field. NZ J Science 14, 959—970.
  • 1972 (WFG) Optical spectra and equilibrium distribution of polysulfide ions in aqueous solutions at 20° C. Inorganic Chemistry 11, 1201—1207.
  • 1973 (WFG, PR Kyle, GL Lyon) Present volcanic activity on Mt Erebus, Ross Island, Antarctica. Geology 1, 135—136.
  • 1973 (WFG)The blue supersulphide ion, S2—. J Chem. Soc. DA, 1973, 729—731.
  • 1974 (WFG) The kinetics of polysulfide-thiosulfate disproportionation up to 240° C. Inorganic Chemistry 13, 1730—1733.
  • 1974 (WFG) Equilibria involving polysulfide ions in aqueous solutions up to 240° C. Inorg. Chem. 13, 1724—1730.
  • 1974 (WFG) The chemistry of the crater lake on Mt Ruapehu (New Zealand) during and after the 1971 active period. NZ J Science 17, 133—145.
  • 1974 (GL Lyon and WFG) Geothermal activity in Victoria Land (Antarctica). NZ J Geol. Geophys. 17, 511—521.
  • 1975 (WFG and RB Glover) The use of chemical indicators in the surveillance of volcanic activity affecting the crater lake on Mt Ruapehu, New Zealand. Bull. Volcanol. 39, 70—82.
  • 1975 (WFG) A simple method for the collection and analysis of volcanic gases. Bull. Volcanol. 39, 132—145.
  • 1975 (F LeGuern,WFG, H Tazieff, P Zettwong) Etude des fluctuations de la phase gazeuse a l’etang de lave Erta’Ale (Ethiopie).C R Acad Sc.(Paris) 280, 1959— 1962.
  • 1975 (F LeGuern, WFG, H Tazieff) Eqilibres chimiques des gaz eruptifs du volcan Erta’Ale (Etiopie). C R Acad Sc.(Paris) 280, 2093—2095.
  • 1975 (WFG) Variations in the carbon, sulfur and chlorine contents of volcanic gas discharges from White Island, New Zealand. Bull. Volcanol. 39, 15—27.
  • 1976 ( WFG and F LeGuern) The chemistry of magmatic gases from Erta’Ale, Ethiopia. Geochim. Cosmochim. Acta 40, 25—30.
  • 1976 (WFG) Geothermal ice caves on Mt Erebus, Ross Island, Antarctica. NZ J Geol. Geophys. 19, 365—372.
  • 1978 (WFG) The isotopic composition of sulphur in sedimentary rocks bordering the Taupo Volcanic Zone. In: NZ DSIR Bull. 218, 57—64.
  • 1978 (GL Lyon, WFG , RJ Singleton, GP Glasby) Isotopic and chemical composition of submarine geothermal gases from the Bay of Plenty. In: NZ DSIR Bull. 218, 65—67.
  • 1978 ( WFG and GP Glasby) The influence of thermal activity on the trace metal distribution in marine sediments around White Island, New Zealand. In: NZ DSIR Bull. 218, 121—126.
  • 1978 (WFG) The isotopic composition of waters from the El Tatio geothermal area, Northern Chile. Geochim. Cosmochim. Acta 42, 979—988.
  • 1979 (WFG) The application of mineral phase diagrams in geothermal corrosion. Proc. 1st NZ Geothermal Workshop, University of Auckland, pp.214—226.
  • 1980 (WFG) Geothermal gas equilibria. Geochim. Cosmochim. Acta 44, 2021—2032.
  • 1981 (WFG) Geothermal mineral equilibria. Geochim. Cosmochim. Acta 45, 393— 410.
  • 1982 (WFG) Carbon—13 exchange between CO2 and CH4 under geothermal conditions. Geochim. Cosmochim. Acta 46, 159—165.
  • 1982 (T Torgerson, JE Lupton, DS Sheppard, WFG) Helium isotope variations in the thermal areas of New Zealand. J Volcanol. Geotherm. Res. 12, 283—298.
  • 1982 (WFG and MK Stewart) Processes controlling the isotopic composition of steam and water discharges from steam vents and steam heated pools in geothermal areas. Geothermics 11, 71—80.
  • 1982 (PR Kyle, RR Dibble, WFG, JR Keys) Volcanic activity associated with the anorthoclase phonolite lava lake, Mt Erebus, Antarctica. In: Antarctic Geoscience (Ed C.Craddock), The University of Wisconsin Press, 735—745.
  • 1982 (WFG) Geothermal mineral equilibria (Reply to a comment by MA Grant). Geochim. Cosmochim. Acta 46, 2681—2683.
  • 1982 (WFG) The chemical and isotopic composition of gas discharges from New Zealand andesitic volcanoes. Bull. Volcanol. 45, 253—255.
  • 1983 (WFG, R Gonfiantini, BL Jangi, AH Truesdell) Isotopic and chemical composition of Parbati Valley geothermal discharges, NW Himalaya, India. Geothermics 12, 199—222.
  • 1983 (WFG, R Gonfiantini, C Panichi) Geothermal Systems. In: Guidebook on Nuclear Techniques in Hydrology, IAEA Techn. Report 91, pp.359—379.
  • 1983 (WFG) Chemical surveillance of active volcanoes. In: Forecasting Volcanic Events (Eds. H Tazieff and JC Sabroux), Elsevier, Amsterdam, 312—322.
  • 1984 (WFG) Mass transfer in hydrothermal alteration systems. Geochim. Cosmochim. Acta 48, 2693—2711.
  • 1985 (WFG) Construction of thermodynamic stability diagrams involving dioctahedral potassium clay minerals. Chem. Geol. 49, 231—242.
  • 1985 (WFG) The use of gas chemistry in delineating the origin of fluids discharged over the Taupo Volcanic Zone. Proc. IAVCEI 1985 Congress, Auckland NZ, Sess.V, pp.47—50.
  • 1986 (WI Rose, RL Chuan, WFG, PR Kyle, B Symonds) Rate of sulfur dioxide and particle emissions from White Island volcano, New Zealand, and an estimate of the flux of major gaseous species. Bull. Volcanol. 48, 181—188.
  • 1986 (WFG) Graphical techniques for the evaluation of water-rock equilibration conditions by use of Na, K, Mg and Ca contents of discharge waters. Proc. 8th NZ Geothermal Workshop, University of Auckland, pp.37—44.
  • 1987 (WFG) Redox processes governing the chemistry of fumarolic gas discharges from White Island. Appl. Geochemistry 2, 143—161.
  • 1987 (Y Sano, H Wakita, WFG ) Island arc tectonics of New Zealand manifested in helium isotope data. Geochim. Cosmochim. Acta 51, 1855—1860.
  • 1987 (WFG, M Martini, E Corazza) The effects of hydrothermal processes on the chemistry of some recent volcanic gas discharges. Periodico Mineralogia 55, 15—28.
  • 1988 (WFG, AA Minissale, G Scandiffio) Isotopic and chemical assessment of geothermal potential of the Colli Albani area, Latium region, Italy. Appl. Geochemistry 3, 475—486.
  • 1988 (WFG) The interplay of magmatic and hydrothermal processes in the formation of volcanic and geothermal fluid discharges. Proc. Int. Conference on Volcanoes, Kagoshima (Japan), pp.843—847.
  • 1988 (WFG) Geothermal solute equilibria. Derivation of Na-K-Mg-Ca-geoindicators. Geochim. Cosmochim. Acta 52, 2749—2765.
  • 1989 (WFG , JW Hedenquist, BF Houghton, PM Otway, RG Allis) Research drilling into the volcanic-hydrothermal system on White Island. EOS Trans. Am. Geophys. Union 70. 98—109.
  • 1989 (WFG) The chemical and isotopic position of the Ohaaki Field within the Taupo Volcanic Zone. Proc. 11th NZ Geothermal Workshop, University of Auckland, pp.81—88.
  • 1989 (WFG and DS Sheppard) Variations in the temperature and chemistry of White Island fumarole discharges, 1972—85. In: NZ Geol. Survey Bull. 103, 119—126.
  • 1989 (WFG) Processes controlling CO2— and Cl contents of thermal discharges from the Taupo-Rotorua volcanic-magmatic- hydrothermal systems, New Zealand. Proc.6th Int. Symp. on Water-Rock Interaction, Malvern (UK), pp.259—262.
  • 1990 (B Marty and WFG ) Major and rare gases at White Island volcano, New Zealand: origin and flux of volatiles. Geophys. Res. Letters 17, 247—250.
  • 1990 (WFG, N Garcia P., A Londono C., L Rodriguez V., N Rojas G., ML Calvache V.) The chemistry of fumarolic vapor and thermal spring discharges from the Nevado del Ruiz volcanic-magmatic-hydrothermal system, Colombia. J. Volcanol. Geotherm. Res. 42, 13—39.
  • 1990 (WFG) Water and gas chemistry of Lake Nyos, Cameroon, and its bearing on the eruptive process. J. Volcanol. Geotherm. Res. 42, 337—362.
  • 1990 (WFG and S Matsuo) Evaluation of results from second and third IAVCEI Field Workshops on volcanic gases, Mt Usu, Japan, and White island, New Zealand. Appl. Geochemistry 6, 125—141.
  • 1991 (WFG ,Y Sano, HU Schmincke) CO2 rich gases from Lakes Nyos and Monoun (Cameroon), Laacher See (Germany), Dieng (Indonesia), and Mt Gambier (Australia) — Variations on a common theme. J Volcanol. Geotherm. Res. 45, 311—323.
  • 1991 (WFG) Redox processes accompanying the deposition of minerals in volcanic- magmatic-hydrothermal systems. Geol. Survey of Japan Report 277, pp.91—96.
  • 1991 (WFG) Chemical techniques in geothermal exploration. In: UNITAR / UNDP Handbook on Application of Geochemistry in Geothermal Reservoir Development, pp. 119—144.
  • 1991 (WFG) Isotopic composition of geothermal water and steam discharges. In: UNITAR/UNDP Handbook on Application of Geochemistry in Geothermal Reservoir development, pp.253—273.
  • 1991 (KL Brown, JG Webster, WFG, GL Lyon) A note on gases dissolved in the deep weaters of Lake Vanda. Antarctic Record 11, 14—18.
  • 1992 (MF LeCloarec, P Allard, B Ardouin, WFG, DS Sheppard) Radioactive isotopes and trace elements in gaseous emissions from White Island, New Zealand. Earth and Planet. Sci. Letters 108, 19—28.
  • 1992 (WFG and R Corrales S) The isotopic and chemical composition of water and gas discharges from the Guanacaste geothermal province, Costa Rica. Appl. Geochemistry 7, 309—332.
  • 1992 (WFG and RB Glover) Tectonic regime and major processes governing the chemistry of fluid discharges from the Rotorua geothermal field, New Zealand. Geothermics 21, 121—140.
  • 1992 (AG Reyes and WFG ) Petrology and fluid chemistry of magmatic- hydrothermal systems in the Philippines. Proc. 7th Int. Symp. on Water-Rock interactions, Park City (Utah, US), pp. 1341—1344.
  • 1992 (WFG) The composition of gases in geothermal and volcanic systems as a function of tectonic setting. Proc. 7th Int. Symp. on Water-Rock interactions, Park City (Utah, US), pp. 873—878.
  • 1992 (WFG) Isotopic shifts in waters from geothermal and volcanic systems along convergent plate boundaries and their origin. Earth Planet. Sci. Letters 113, 495—510.
  • 1992 (WFG) Magma degassing and mineral deposition in hydrothermal systems along convergent plate boundaries. Econ. Geology 87, 1927—1944.
  • 1992 (GL Lyon and WFG) The isotopic geochemistry of hot spring gases and waters from Coromandel and Hauraki. Proc.14th NZ Geothermal Workshop, University of Auckland, pp.57—62.
  • 1992 (WFG, R Corrales S, L Vaca) The isotopic composition and origin of thermal and non-thermal waters from the Miravalles geothermal field, Costa Rica. IAEA (Vienna) Techn. Doc. Series 641, 201—218.
  • 1992 (WFG, D Paniagua de G, AR Roldan M) The isotopic and chemical composition of water and gas discharges from the Zunil geothermal system, Guatemala. IAEA (Vienna) Tech. Doc. Series 641, 245—278.
  • 1992 (WFG) IAEA interlaboratory comparative geothermal water analysis program. IAEA (Vienna) Tech.Doc. Series 641, 439—456.
  • 1993 (WFG, Y Sano, H Wakita) The isotopic composition of He, and CO2 and CH4 contents of gases produced along the New Zealand part of a convergent plate boundary. Geochim. Cosmochim. Acta 57, 3427—3455.
  • 1993 (JW Hedenquist, SF Simmons, WFG, CS Eldridge) White Island, New Zealand, volcanic-hydrothermal system represents the geochemical environment of high sulfidation Cu and Au ore deposition. Geology 21, 731—734.
  • 1993 (WFG and RJ Poreda) Helium isotopic and chemical composition of gases from volcanic-hydrothermal systems in the Philippines. Geothermics 22, 369—380.
  • 1993 (WFG) Redox control of gas compositions in Philippine volcanic-hydrothermal systems. Geothermics 22, 575—587.
  • 1993 (AG Reyes, WFG, JRM Saleras, ND Salonga, MC Vergara) Petrology and geochemistry of Alto Peak, a vapor-cored hydrothermal system, Leyte Province, Philippines. Geothermics 22, 479—519.
  • 1993 (H Shinohara, WFG, K Kazahaya, JW Hedenquist) Geochemistry of volcanic gases and hot springs of Satsuma-Iwojima: Following Matsuo. Geochem. Journ. 27, 271—285.
  • 1993 (A Ono, Y Sano, H Wakita, WFG ) Carbon isotopes of methane and carbon dioxide in hydrothermal gases of Japan. Geochem. Journ. 27, 287—295.
  • 1993 (WFG) Reply to P.Blattner: Andesitic water — a phantom of the isotopic evolution of water-silicate systems. Earth Planet. Sci. Lett. 120, 519—522.
  • 1994 (JW Hedenquist, Y Matsuhisa, E Izawa, NC White, WFG, M Aoki, M Kusakabe) Geology and geochemistry of high sulfidation Au-Cu mineralization in the Nansatsu district (Japan). Econ. Geol. 89, 1—30.
  • 1994 (GL Lyon and WFG ) Isotopic and chemical composition of natural gases from the South Island, New Zealand. Proc. 1994 NZ Petroleum Conf., pp.361–369.
  • 1994 (WFG, DS Sheppard, BW Robinson, MK Stewart, and GL Lyon) Geochemical structure and position of the Waiotapu geothermal field, New Zealand. Geothermics 23, 599–644.
  • 1995 (WFG) Geochemical exploration of a "difficult" geothermal system: Paraso, Vella Lavella, Solomon Islands. Proc. World Geotherm. Congress 1995 (Florence, Italy), vol.2, pp.995–1000.
  • 1995 (WFG) Composition of fluids in geothermal systems of the Taupo Volcanic Zone, New Zealand, as a function of source magma. Proc. 8th Int. Symp. on Water-Rock interactions, Vladivostok (Russia), pp.9–12.
  • 1995 (WFG) Variations in the chemical and isotopic compositions of fluids discharged over the Taupo Volcanic Zone, New Zealand. J Volcanol. Geotherm. Res. 68, 89–116.
  • 1995 (WFG) Correlation among CO2, Cl, 3He and heat discharged from geothermal systems of the Taupo Volcanic Zone, New Zealand. Proc. PACRIM Conference, Auckland (NZ), pp.233–238.
  • 1995 (WFG, MK Stewart, Y Sano, GL Lyon, RL Goguel) Isotopic and chemical composition of waters and gases from the East Coast accretionary prism, New Zealand. IAEA (Vienna) Tech. Doc. Series 788, 209–231.
  • 1995 (WFG) Composition of magmatic components in hydrothermal fluids. In: Magmas, Fluids and Ore Deposits (Ed. JFH Thompson), Mineral. Assoc. Canada, Short Course Series 23, 247–261.
  • 1996 (GL Lyon, WFG, Y Sano) Variations in the chemical and isotopic composition of Taranaki gases and possible causes. Proc. 1996 NZ Petroleum Conf., pp.171–174.
  • 1996 (WFG) Are Tokaanu Cl waters the outflow from Ketetahi or Hipaua? Proc. 18 NZ Geothermal Workshop, University of Auckland, pp. 175–182.
  • 1996 (S Yanagiya, K Kasai, KL Brown, WFG) Chemical characteristics of the deep geothermal fluid in the Kakkonda geothermal system, Iwate prefecture. Chinetsu 33, 1–18.
  • 1996 (WFG) Chemical composition of volcanic gases. In: Monitoring and Mitigation of Volcanic Hazards (Eds. Scarpa-Tilling), Springer Verlag, Heidelberg, 221–256.
  • 1997 (WFG) The origin and evolution of fluids in magmatic-hydrothermal systems. In: Geochemistry of Hydrothermal Ore Deposits 3rd Ed. (Ed. H Barnes), John Wiley & Sons Inc., New York, 737–796.
  • 1997 (WFG) Relative importance of thermodynamic and kinetic processes in governing the chemical and isotopic composition of carbon gases in high heatflow sedimentary basins. Geochim. Cosmochim. Acta 61, 3762–3785.
  • 1998 (T Pichler, WFG, BIA McInnes, MD Hannington, B Duck) Fe-sulfide formation due to seawater-gas-sediment interaction in a shallow-water hydrothermal system, Lihir Island, Papua New Guinea. Geology (in press).
  • 1998 (TP Fischer, WFG, Y Sano, SN Williams) Fluxes and sources of volatiles discharged from Kudryavy, a subduction zone volcano, Kurile Islands, Russia. Earth Planet. Sci. Letters (in press).

In preparation

  • (WFG and RJ Poreda) The chemical and isotopic composition of gases from high temperature fumaroles on the Galapagos hot spot and their origin.To be published in: Geochim. Cosmochim. Acta.
  • (WFG) Interaction of magmatic volatiles with water and rocks within the White Island volcanic-hydrothermal system. Special JVGR Issue in honor of Werner F Giggenbach (Ed. H Shinohara). To be published in J Volcanol. Geotherm. Res.
 
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