Table 1.

Bulk and biomarker data for Mesoproterozoic shales of the El Mreïti Group, Taoudeni Basin, from drill core S2

Specs	Sample ID
	06	08	11	13	14	17	20	22	29	32	33
Formation	Touirist	Touirist	Touirist	Touirist	Touirist	Touirist	En Nesoar	En Nesoar	En Nesoar	En Nesoar	En Nesoar
Depth	139.60	140.25	140.55	141.90	142.20	151.95	185.40	187.30	200.01	203.10	206.08
TOC, wt %	10.0	16.5	16.2	31.7	15.9	15.8	2.1	11.1	12.6	14.8	8.5
Nbulk, wt %	0.3	N.A.	0.5	0.7	0.5	0.5	0.1	0.3	0.3	0.3	0.2
δ13Corg, ‰	−31.5	N.A.	−31.2	−33.9	−31.2	−31.7	−31.7	−32.5	−34.9	−34.3	−35.5
δ15Nbulk, ‰	4.4	N.A.	4.7	5.1	5.1	4.2	4.6	5.0	6.1	6.1	6.0
S/Hmax*	0.0002	0.0004	0.0002	0.0004	0.0006	0.0004	0.0014	0.0006	0.0011	0.0008	0.0011

N.A., not available; TOC, total organic carbon.

^*Steranes (S) were beneath detection limits in all samples. The S/H_max ratio gives the maximum concentration of C₂₇ steranes relative to bacterial C₂₇ to C₃₅ hopanes (H) that may be present in samples beneath the analytical noise (SI Appendix, SI Methods).