Geochemical Characteristic and Source Correlation of Biodegraded Oils from the Western Halaalate Area of Junggar Basin

Table 1

Gas chromatography data of crude oil and source rock from Hashan area and Mahu Depression.

Types	Wells	Depth (m)	Strata	Pr/Ph	Pr/nC17	Ph/nC18	∑C21^-/∑C22^+	OEP	CPI	Carbon number		Major carbon
Crude oil	Hq 102	454.0~458.0	C	0.53	1.09	1.62	0.12	1.01	1.32	/	0.14	29
		535.2		1.05	0.79	0.45	0.07	1.08	1.03	/	0.19	26
		854.0~860.0		0.58	1.00	1.38	0.22	0.98	1.20	/	0.35	28
	Hq3	1174.0~1183.0		0.78	0.68	0.53	0.80	0.85	1.15	/	/	26
		1324.0~1328.0		0.87	0.57	0.80	1.03	1.01	1.27	/	2.17	17
		1354.0~1358.0		0.81	0.62	0.96	1.09	0.98	0.95	/	1.68	17
		1360.0~1374.0		0.37	0.79	1.51	0.70	1.08	0.97	/	2.51	23
	Hq 6	302.2		0.87	1.60	2.30	0.79	1.12	1.00	14~29	0.66	29
		301.4~301.9		0.88	1.50	2.20	0.82	1.10	0.99	14~29	0.73	29
		648.1~648.2		0.85	1.40	2.00	0.81	1.06	1.02	13~28	0.79	28
	Hq 101	1452.5		0.64	1.51	2.12	0.60	1.06	0.93	14~30	1.17	24
		1742.5		0.91	1.58	2.00	0.63	1.09	1.18	14~31	1.36	23
Mudstones in Hashanxi area	Hq 6	1325.0~1335.0	P1f	0.45	1.01	2.54	0.66	1.03	1.08	/	1.09	23
		1360.5		0.55	0.98	2.60	1.21	1.02	1.08	/	1.86	17
		1365.0~1380.0		0.38	1.04	2.67	0.53	1.02	1.07	/	1.18	24
		1410.0~1425.0		0.48	0.71	1.37	0.53	0.85	0.85	/	1.34	24
		1460.0~1470.0		0.46	0.86	1.66	0.43	0.92	0.97	/	1.01	26
		1476.0~1486.0		0.37	0.91	2.02	0.42	0.96	1.07	/	1.02	24
		1494.0~1502.0		0.27	0.62	1.65	0.48	0.98	0.96	/	1.35	22
		1700.0~1752.0		0.44	0.92	2.17	0.67	1.02	1.05	/	1.20	24
		2541.7		0.64	1.32	3.69	3.34	1.06	0.84	/	3.95	17
		2540.0~2540.6		0.59	1.21	5.90	0.81	0.91	1.32	14-29	0.99	17
		2703.1		0.40	1.12	4.46	0.97	1.05	1.21	14-31	1.70	17
	Hq 1	2099.9	P1f	0.75	0.72	1.01	0.73	0.98	1.01	14-32	1.84	22
		2156.4		0.37	1.55	7.42	0.80	0.91	1.13	14-32	1.52	17
Mudstones in Mahu Depression	Fn4	4227.2	P1f	0.96	1.38	1.36	0.52	1.17	1.20	12-36	1.25	25
		4228.5		0.97	1.27	1.33	0.51	1.18	1.20	13-37	1.25	25
	Fn1	3119.0~3134.0	P1f	1.07	1.35	1.86	0.94	1.36	1.19	10-36	1.19	17
		3119.0~3134.0		1.09	1.47	2.00	0.78	1.27	1.08	10-36	1.76	23
		3960.0~3976.0		0.96	1.44	1.85	1.91	1.10	1.12	9-36	2.31	17

Note: OEP: odd-even predominance index; CPI: carbon preference index (CPI); /: no data.