Mantle-derived fluids in Central Mediterranean: Geochemical and geophysical constrains on sources of fluids and migration

Caracausi, A.
Grassa, F.
Pennino, V.
Rizzo, A.
Sulli, A.

Publication date

January 2013

Abstract

The geodynamics of the central Mediterranean is characterized by the interaction between the European plate and the African\u2019s. In this setting Sicily is a sector of the Appenine-Maghrebide accretionary prism, which is located between two areas affected by extensional tectonics (Sicily Channel to the south and the Thyrrenian back arc basin to the north). Significant mantle-derived helium (0.4<R/Ra<2.8; R=3He/4He in the sample, Ra in atmosphere) is found in the CH4 and N2-CO2 rich fluids released in central western Sicily, a region without evidence of recent magmatism. CH4- dominated gases are released from mud volcanoes localized in an area of both low heat flow and seismicity. On the contrary CO2 is mainly associated to the thermal gro...