Premium
Helium isotopes and tectonics in southern Italy
Author(s) -
Sano Yuji,
Wakita Hiroshi,
Italiano Francesco,
Nuccio Mario P.
Publication year - 1989
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/gl016i006p00511
Subject(s) - forearc , geology , subduction , volcano , volcanic arc , tectonics , plate tectonics , structural basin , paleontology , earth science , cenozoic , seismology
Geodynamic evolution of southern Italy can be understood within the framework of the Mediterranean‐Alpine System. Subduction of a plate along the Sicily‐Calabrian forearc under the Tyrrhenian Sea has been suggested by many geophysicists, although it is not yet confirmed and remains somewhat controversial. Helium isotope ratios provide useful information on the geotectonic structure of the region. We report here the ³He/ 4 He ratios of terrestrial gas samples from southern Italy. The observed ³He/ 4 He ratios are relatively high in the Eolian volcanic arc region and low in the other areas. Dichotomous explanations are presented. Firstly volcanic arc‐forearc hypothesis suggests the subduction along the Sicily‐Calabrian forearc. Secondly horizontal transport hypothesis is described based on the relationship between the ratios and radial distance from the recent spreading basin in Southern Tyrrhenian Sea.