Geochemical Characteristics and Origins of the Crude Oil of Triassic Yanchang Formation in Southwestern Yishan Slope, Ordos Basin

Table 2

Comparative data of n-alkane and isoprenoid alkanes of samples in Southwestern Yishan Slope.

	Sample number	Reservoir		OEP	/	Pr/Ph	Pr/C17	Ph/C18
Crude oil	S1	Chang 1	12~38	1.09	1.71	1.47	0.97	0.65
	S2	Chang 2	11~37	1.04	1.33	1.01	0.62	0.63
	S3	Chang 2	11~37	1.01	0.84	1.34	0.79	0.51
	S4	Chang 2	11~37	1.05	1.22	1.39	0.56	0.38
	S5	Chang 3	12~36	1.05	0.98	0.91	0.53	0.49
	S6	Chang 3	12~36	1.08	1.25	0.99	0.37	0.36
	S7	Chang 4 + 5	9~36	1.05	2.47	1.31	0.85	0.52
	S8	Chang 4 + 5	12~38	1.04	1.06	1.20	0.22	0.19
	S9	Chang 6	12~36	1.01	2.39	1.14	0.41	0.36
	S10	Chang 6	11~37	1.06	1.01	0.96	0.78	0.75
	S11	Chang 7	11~37	1.05	1.03	0.97	1.06	0.99
	S12	Chang 7	11~37	1.05	1.35	0.98	0.73	0.72
	S13	Chang 8	11~38	1.05	0.93	1.02	0.66	0.65
	S14	Chang 8	11~34	1.03	1.49	1.07	0.78	0.71
	S15	Chang 8	11~38	1.01	0.77	1.17	0.61	0.51
	S16	Chang 8	11~37	1.03	0.78	1.17	0.97	0.81
	S17	Chang 9	12~38	1.02	0.99	1.12	0.43	0.32
	S18	Chang 9	12~38	1.01	1.10	1.01	0.37	0.31
	S19	Chang 10	12~38	1.08	1.20	1.27	0.25	0.18
	S20	Chang 10	12~38	1.01	0.97	1.38	0.24	0.16
Source rock	R1	Yan 6	12~36	1.07	1.68	2.14	0.46	0.22
	R2	Yan 7	12~36	1.00	4.45	1.89	0.55	0.16
	R3	Yan 9	12~36	1.20	1.87	2.90	0.76	0.25
	R4	Chang 4 + 5	12~36	1.07	1.05	2.05	0.54	0.12
	R5	Chang 6	12~36	1.05	0.96	2.11	0.87	0.25
	R6	Chang 8	12~38	1.02	1.21	2.35	0.55	0.19
	R7	Chang 9	12~38	1.02	0.98	2.70	0.81	0.25
	R8	Chang 7	12~37	1.02	1.44	0.91	0.86	0.92
	R9	Chang 7	11~37	1.03	0.97	1.23	0.76	0.55
	R10	Chang 7	12~35	1.11	2.12	1.30	0.49	0.39
	R11	Chang 7	12~33	1.00	2.13	1.44	0.39	0.28
	R12	Chang 7	12~37	0.99	1.11	1.46	0.55	0.36
	R13	Chang 7	13~35	1.02	1.08	1.47	0.68	0.51
	R14	Chang 7	14~35	1.01	0.58	1.03	0.75	0.73
	R15	Chang 7	12~36	1.03	1.29	1.10	0.55	0.42
	R16	Chang 7	12~38	0.99	1.46	1.07	0.20	0.18
	R17	Chang 7	12~38	1.02	0.98	1.27	0.40	0.27