Table 3.

The bulk H, C and N contents and H and N isotopic compositions of various chondrite groups. For the CI, CM and CR chondrites, the values are the averages for multiple samples and the uncertainties are the standard deviations. The large standard deviations for the CM and CR chondrite H abundances and isotopes reflect the variations in degree of alteration, and in the case of the CM isotopes the anomalous Bells meteorite. For Tagish Lake, the values are averages for several lithologies, except for H abundances and isotopes that are for the most primitive (least heated?) lithology 5b. The OC, CV and CO chondrites are represented by the most primitive and volatile-rich (i.e., least metamorphosed) members of their groups (Semarkona, Kaba, and DOM 08006, respectively), hence no uncertainties are given. The data are from Alexander et al. (2012) and Alexander et al. (2017b).

	H (wt.%)	C (wt.%)	N (wt.%)	δD (‰)	δ15N (‰)
OC	0.12	0.59	0.01	1616	39
CV	0.23	1.13	0.13	14	−24
CO	0.46	1.20	0.02	0	8
CM	1.15±0.18	1.95±0.34	0.10±0.03	−53±150	44±66
CI	1.55±0.02	3.65±0.24	0.19±0.03	78±7	42±5
Tagish Lake	0.94	4.07±0.10	0.20±0.04	508	66±9
CR	0.49±0.26	1.17±0.12	0.08±0.01	651±135	175±8

The standard ratios for calculating delta values are: D/H=1.5576×10⁻⁴ and ¹⁵N/¹⁴N=3.67×10⁻³.