EVALUATION AND RESTORATION OF THE 1970 VOLCANIC GAS-ANALYSES FROM MOUNT ETNA, SICILY

被引:40
作者
GERLACH, TM
机构
[1] Sandia Laboratories, Albuquerque
基金
美国能源部;
关键词
D O I
10.1016/0377-0273(79)90052-0
中图分类号
P [天文学、地球科学];
学科分类号
07 ;
摘要
The 1970 Mount Etna volcanic gas analyses (Huntingdon, 1973) are among the most reduced volcanic gas samples ever reported. They contain 20-40% H2, 2-3.5% CO, and 2-5% H2S. Calculated oxygen fugacities for most of the analyses are well below quartz-fayalite-magnetite, several are more reduced than magnetite-wustite and all are many orders of magnitude less than those measured by Sato and Moore (1973) in the gas-streams of the collection sites at the time the samples were taken. The analyses show no similarity to calculated equilibrium compositions at any temperature. Deviations between analytical and equilibrium compositions indicate the gases have undergone extensive reduction involving mainly loss of oxygen. There also is limited evidence of sulfur loss. The reduced analyses are not the products of unusually reduced lavas, but originated from reactions of the erupted gases with the metal sampling device used in the collection procedure. The oxygen deficiencies of the analyses have been restored using the atomic hydrogen, carbon and sulfur data of Huntingdon and the oxygen fugacity data of Sato and Moore. The restored analyses are much more representative of the erupted gases which were remarkably rich in CO2 (15-35%) and SO2 (15-35%), and they show relatively steady compositions at each collection site over periods of observation ranging from hours to days. © 1979.
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页码:165 / 178
页数:14
相关论文
共 15 条
[1]  
Carter, Petrology and geochemistry of the lavas of Mt. Etna, Sicily, D. Phil. Thesis, Oxford, (1976)
[2]  
Ellis, Chemical equilibrium in magmatic gases, American Journal of Science, 255, pp. 416-431, (1957)
[3]  
Eugster, Wones, Stability relations of the ferroginous biotite, annite, J. Petrol., 3, pp. 82-125, (1962)
[4]  
Gerlach, Nordlie, The C-O-H-S gaseous system
[5]  
Part I, Composition limits and trends in basaltic cases, American Journal of Science, 275, pp. 353-376, (1975)
[6]  
Giggbach, LeGuern, The chemistry of magmatic gases from Erta'Ale, Ethiopia, Geochim. Cosmochim. Acta, 40, pp. 25-30, (1976)
[7]  
Graeber, Modreski, Gerlach, Compositions of gases collected during the 1977 East Rift eruption, Kilauea, Hawaii, J. Volcanol. Geotherm. Res., 5, pp. 337-344, (1979)
[8]  
Huntingdon, The Collection and Analysis of Volcanic Gases from Mount Etna [and Discussion], Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 274, pp. 119-128, (1973)
[9]  
LeGuern, The Collection and Analysis of Volcanic Gases, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 274, pp. 129-135, (1973)
[10]  
Nordlie, The composition of the magmatic gas of Kilauea and its behavior in the near surface environment, American Journal of Science, 271, pp. 417-463, (1971)