Table 1 Organic geochemistry of Red Stone samples with relative abundance of total organic carbon (TOC) (% dry weight), stable isotopic composition of the bulk organic carbon (‰), and concentration of lipid biomarkers (µg·g dw⁻¹)

	Upper Zone	U1	U2	Sandstones	Mudstones	Evaporites spot1	Evaporites spot2	Lower Zone
TOC (% dw)	0.10	0.02	0.02	0.02	0.10	0.10	0.11	0.06
δ13C (‰)	−26.5	−26.3	−25.6	−25.8	−21.3	−20.6	−19.5	−25.3
n-alkanes (16-31)	0.12	0.14	0.25	0.09	0.48	0.07	0.54	0.13
pristane	0.01	n.d.	n.d.	n.d.	n.d.	n.d.	0.01	0.01
phytane	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	0.01	n.d.
heptadecene	0.13	0.07	n.d.	n.d.	n.d.	n.d.	n.d.	0.19
Hopanes	n.d.	n.d.	n.d.	n.d.	0.06	n.d.	n.d.	n.d.
br-alkanes^a	0.07	0.06	0.08	0.08	0.05	0.06	0.13	0.05
n-fatty acids (14-20)	1.85	0.95	1.35	1.47	1.92	1.75	2.42	0.59
MUFA (16-18)^b	0.10	0.05	0.06	0.03	0.10	0.06	0.04	0.05
Iso-C17:0^c	n.d.	n.d.	n.d.	n.d.	n.d.	n.d.	0.01	n.d.
MMe-10-C16:0^d	n.d.	n.d.	n.d.	n.d.	0.28	n.d.	n.d.	n.d.
Total sum of fatty acids^e	1.95	1.91	1.41	1.50	2.30	1.81	2.47	0.64
n-fatty acids/n-alkanes	16	7	5	17	4	25	4	4

Lipid concentration was obtained by integrating the peak areas of each compound and applying the response factor of deuterated analogs (tetracosane-D₅₀ in the apolar fraction and myristic acid-D₂₇ in the acidic fraction) of known concentration added to the sample prior to extraction. The range of carbon numbers is indicated in brackets for the straight chain or normal (n) alkanes and fatty acids, as well as for the monounsaturated fatty acids (MUFA). n.d.: not detected,
^aSum of branched alkanes, in particular monomethyl alkanes of 16, 18 and 20 carbons,
^bSum of monounsaturated fatty acids from 16 to 18 carbons,
^cHexadecanoic acid, 15-methyl,
^d10-Methyl hexadecanoic acid.
^eTotal sum of fatty acids, including normal, branched and unsaturated moieties.

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