Carbon, helium, neon and argon isotopes in a Po basin (northern Italy) natural gas field

Geochemistry of shallow aquifers and soil gas surveys in a feasibility study at the Rivara natural gas storage site (Po Plain, Northern Italy)

“…The 3 He/ 4 He data (free gas of sample 1, R/R a = 0.04, where R is the 3 He/ 4 He of the sample and R a the same ratio in the air, Table 9) evidence prevalent He production through the decay of radiogenic elements within the crust, having an average end-member value of R/R a = 0.02 (Ozima and Podosek, 2002). This observation is congruent with He ratios of other CH 4 -dominated gaseous manifestations located in the Po Plain and surroundings (Elliot et al, 1993;Minissale et al, 2000;Tassi et al, 2012), where no significant contributions from other source than crust were recognized (Minissale et al, 2000). In order to discriminate the various possible sources of dissolved CO 2 in the investigated waters, the pristine C isotopic composition of CO 2 interacting with groundwater has been calculated (Table 7), considering relationships reported by many authors (Deines, 1970;Mook et al, 1974;Favara et al, 2002).…”

Geochemical and Geomorphological Analyses on Liquefaction Occurred During the 2012 Emilia Seismic Sequence

“…Helium contents are negligible, resulting slightly higher than Air Saturated Water (ASW). This datum is congruent with other CH 4 -dominated gaseous manifestations located in the Po Plain (Elliot et al 1993;Minissale et al 2000;Tassi et al 2012), where no significant contributions from other source than crust were recognized (Minissale et al 2000).…”

Deep Fluids in Sedimentary Basins

“…Fluids in extensional basins, such as the Pannonian and Paris Basins, or in continental rifts have clear mantle-derived noble gas signatures in the form of excess 3 He, 129 Xe, and 21 Ne (Ballentine and O'Nions, 1991). Basins in which there is active sediment loading, such as the Po Basin, Italy, do not have a clearly defined mantle gas signature (Elliot et al, 1993).…”