Fig. 4
From: Mantle-derived fluids in the Nankai Trough Kumano forearc basin
Depth profiles for 222Rn 3He/20Ne, air-corrected 3He/4He, and 4He/20Ne. The air-corrected 3He/4He versus depth plot also indicates the mantle contribution to the total helium in percent air-corrected (the rest would be crustal helium). Sample #2968.5 is not shown in the 3He/20Ne and 4He/20Ne profiles (see text for explanation). Samples from Exp 338 are plotted as blue open diamonds; those from Exp 348 are shown as black squares. 222Rn data from Tobin et al. (2015)