Helium-3 Distribution in Western Turkey

Year 1988, Volume: 108 Issue: 108, 35 - 42, 01.01.1988

Nilgün Güleç

Abstract

 In this study, to investigate the mantle-crust interaction in Western Turkey, geothermal fluids
from various locations are analyzed for their
3He/4He ratios. The results reveal a mixing between mantle - and
(continental) crustal - helium components. The distribution of mantle-helium, which is characterized by high
3He/4He ratios, does not show any correlation with the spatial and/or temporal distribution of the surface
volcanics in the region, but appears to be governed by the distribution of tectonic deformation. The lack of any
correlation between the distribution of mantle-helium and surface volcanism suggests that helium, now degassing
from mantle, has most probably entered the crust in association with the melts emplaced at deeper levels. The
fault systems of the present extensional tectonics are thought to have had an efficient role in the escape of helium
to the surface through the brittle parts of crust.

Keywords

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References

• Andrews, J.N., 1985, The isotopic composition of radiogenic He and its use to study groundwater movement in confined aquifer : Chem. Geol., 49, 339 - 351.
• Benson, B.B. and Krause, D.J., 1976, Empirical laws for dilute aqueous solutions of non - polar gases: J. Chem. Phys., 64, 689 - 709.
• Condomines, M.; Gronvold, K.; Hooker, P.J.; Muehlenbachs, K.; O'Nions, R.K; Oskarsson, N. and Oxburgh, E.R., 1983, Helium, oxygen, strontium and neodymium isotopic relationships in Icelandic volcanics : Earth Planet. Sci. Lett., 66, 125 -136.
• Craig, H.; Lupton, J.E. and Horibe, Y., 1978, A mantle He component in circum — Pacific volcanic gases : Hakone, the Marianas, and Mt. Lassen ; in : Advances in Earth and Planetary Sciences, Jr. E.C. Alexander and Ozima (eds.), Japan Sci. Soc. Press, 3-16 , Tokyo.
• and Lupton, J.E., 1981, Helium - 3 and mantle volatiles in the ocean and oceanic crust; in : The Sea, vol.7 : The oceanic Lithosphere : C. Emiliani (ed.), J. Wiley and Sons, 391 - 428.
• Hermance, J.F., 1982,Magnetotelluric and geomagnetic deepsounding studies in the crust and upper mantle; in : Continental and Oceanic Rifts, G. Palmason (ed.), Geodynamic Series, v.8, American Geophysical Union, Washington, D.C., Geol.Soc. Am.Boulder, Colorado, 169-192.
• Hooker, P.J.; O'Nions, R.K. and Oxburgh, E.R., 1985, Helium isotopes in North Sea gas fields and the Rhine Rift : Nature, 318, 273 - 275.
• İÜTF (İstanbul Üniversitesi Tıp Fakültesi), 1971, Tür- kiye Maden Sulan — 2, Marmara Bölgesi İstanbul Üniversitesi Tıp Fakültesi, Hidroklimatoloji Kür- süsü, 335.
• , 1975, Türkiye Maden Suları — 3, Ege Bölgesi : Istanbul Üniversitesi Tıp Fakültesi, Hidroklima- oloji Kürsüsü, 335.
• Kennedy, B.M.; Lync, M.A.; Reynolds, J.H. and Smith S.P., 1985, Intensive sampling of noble gasses in fluids at Yellowstone : I. Early overview of the data; regional patterns : Geochim. Cosmo- chim. Acta, 49, 1251 - 1261.
• Kurz, M.D.; Jenkins, W.J.; Hart, S.R. and Clauge, D., 1983, Helium isotopic variations in volcanic rocks from- Loihi Sea mount and the island of Hawaii : Earth and Planet.Sci.Lett., 66, 388-406.
• Lupton, J.E., 1983, Terrestrial inert gases : Isotope tracer studies and clues to primordial components in the mantle : Ann. Rev. Earth Planet. Sci. Lett., 11, 371 -414.
• Mamyrin, B.A. and Tolstikhin, I.N., 1984, Helium iso- topes in Nature : Elsevier, 273, Amsterdam.
• Oxburgh, E.R.; O'Nions, R.K. and Hill, R., 1986, Helium isotopes in sedimentary basins : Nature, 324,632 -635.
• Ozima, M. and Podosek, F.A., 1983, Noble Gas Ge- ochemistry : Cambridge University Press, 367, Cambridge.
• Polyak, E.G. and Tolstikhin, I.N., 1985, Isotopic composition of the Earth's helium and the prob- lem of the motive forces of tectogenesis : Chem. Geol., 52,9 - 33.
• Sclater, J.G.; Parsons, B. and Japuart, C., 1981, Oceans and continents : Similarities and differences in the mechanisms of heat loss : J. Geophys. Res., 86, B12,11535-11552.
• Smith, S.P. and Kennedy, B.M., 1985, Noble gas evidence for two fluids in the Baca (Valles Caldera) geothermal reservoir : Geochim. Cos- mochim. Acta, 49, 893 - 902.
• Weiss, R.F., 1969, Piggyback sampler for dissolved gas studies in sealed water samples : Deep Sea s., 15, 659 - 699.