A geothermal reservoir formed near the foot of the active crater of Vulcano Island mainly by condensation of magmatic vapor. Increases in the oxygen composition of the reservoir water are consistent with earthquake-induced increases in the contribution from delta(18)O-rich magmatic condensate to the geothermal reservoir. Subsequent (18)O exchanges during reactions between the highly reactive magmatic condensate and the local rocks at the temporarily increased reservoir temperature cause the reservoir water to shift to lighter (18)O values. These variations in the oxygen composition of the reservoir water are not reflected by the deuterium composition, as the deltaD value of the magmatic condensate released from the magma after the tectonic earthquakes approaches values very similar to that of the water in the geothermal reservoir.
Earthquake-induced changes in the isotopic composition of the water in the geothermal reservoir at Vulcano Island, Italy.
Bolognesi L
1998
Abstract
A geothermal reservoir formed near the foot of the active crater of Vulcano Island mainly by condensation of magmatic vapor. Increases in the oxygen composition of the reservoir water are consistent with earthquake-induced increases in the contribution from delta(18)O-rich magmatic condensate to the geothermal reservoir. Subsequent (18)O exchanges during reactions between the highly reactive magmatic condensate and the local rocks at the temporarily increased reservoir temperature cause the reservoir water to shift to lighter (18)O values. These variations in the oxygen composition of the reservoir water are not reflected by the deuterium composition, as the deltaD value of the magmatic condensate released from the magma after the tectonic earthquakes approaches values very similar to that of the water in the geothermal reservoir.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
