Mantle-Derived Helium Emission near the Pohang EGS Site, South Korea: Implications for Active Fault Distribution

Figure 3

(a) N₂/³He versus δ¹⁵N diagram. Each end-member and mixing lines are described in section 4.2. (b) δ¹³C of CO₂ versus 1/CO₂ diagram (modified from Lee et al. [53]). Mantle value of δ¹³C () is from Sano and Marty [30]. The biogenic CO₂ area ranges between δ¹³C values of C3 plant and C4 plant [31]. The air value of δ¹³C and CO₂ concentration are from Lewicki and Brantley [54]. (c) CH₄/³He versus δ¹³C of CH₄ diagram (modified from Sano et al. [55]). Reference data from northeastern Asia is shown together (Sano et al. [55]).

(a)

(b)

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