Volcanogenic CO₂ Degassing in the Songliao Continental Rift System, NE China

Table 3

Reference values for associated parameters of DMM, CAR, ORS, and COS end members used in C-He isotope systematics.

End member	δ^13CCO2 (‰)	C contents (ppm)	^3He/^4He ()	He contents (ppm)	CO2/^3He (×10^9)
DMM	−6.5^a	1920^b	8^a	0.0288^b	1.5^a
CAR	0^c	11400^d	0.05^e	0.00023^d	1000-100000^f
ORS	−18.5^g	12618^j	0.05^e	0.0667^j	1000-100000^f
COS	−11^h	Unknown	0.02^i	Unknown	0.1-100000^f

Data sources: ^a[46], ^b[37], ^c[53], ^d[59], ^e[68], ^f[62], ^g[65], ^h[69], and ⁱ[66]. ^jCalculated based on U-Th decay.