Geochemistry and Genesis of Oil and Gas Seeps in the Junggar Basin, NW China: Implications for Hybrid Petroleum Systems

Table 1

Basic data of oil and gas seeps, selected crude oil, and source-rock samples from the Junggar Basin.

Number	Sample ID	Outcrops/depth (m)	Formation	Types of oil and gas seeps	EOM (%)	SARA fractions (%)
						Saturates	Aromatics	Resins	Asphaltenes
1	NW-1	Wuerhe	K1tg	Bitumen	8.10	7.60	2.80	35.70	44.50
2	NW-2	Wuerhe	K1tg	Bitumen	79.90	9.60	5.10	38.40	36.90
3	NW-3	Wuerhe	K1tg	Oil sand	37.80	7.70	4.40	37.90	40.00
4	NW-4	Heiyoushan	T2k	Oil sand	15.30	8.30	3.70	37.50	42.00
5	NW-5	Heiyoushan	T2k	Crude-oil seep	n.d.	61.70	11.80	15.40	1.10
6	NW-6	Heiyoushan	T2k	Crude-oil seep	n.d.	60.00	12.40	16.10	1.80
7	Ma27	2347–2349	T2k	Crude oil	n.d.	71.07	14.20	11.01	2.90
8	FN1	4254	P1f	Source rock	0.40	57.49	16.07	25.45	0.91
9	FN1	4323	P1f	Source rock	0.60	65.84	12.28	19.01	2.34
10	SW-1	Wusu	E2-3a	Oil sand	1.30	82.40	12.50	4.10	1.00
11	SW-2	Wusu	E2-3a	Oil sand	0.70	75.60	10.40	3.70	0.90
12	SW-3	Wusu	E2-3a	Gas seep	n.d.	n.d.	n.d.	n.d.	n.d.
13	SW-4	Dushanzi	N2d	Gas seep	n.d.	n.d.	n.d.	n.d.	n.d.
14	SW-5	Dushanzi	N2d	Gas seep	n.d.	n.d.	n.d.	n.d.	n.d.
15	SW-6	Dushanzi	N2d	Oil sand	0.10	n.d.	n.d.	n.d.	n.d.
16	Ka 6	3257–3260	E2-3a	Crude oil	n.d.	65.36	13.71	8.36	6.50
17	GQ 1	4954–4956	E2-3a	Crude oil	n.d.	77.35	11.02	8.98	2.54
18	GQ 1	5271	E2-3a	Source rock	0.40	53.99	13.08	15.08	12.05
19	Ka 6	4253	J2x	Source rock	0.50	61.83	14.62	12.95	1.53
20	SM-1	Anjihai	E2-3a	Oil sand	0.10	n.d.	n.d.	n.d.	n.d.
21	SM-2	Anjihai	E2-3a	Oil sand	0.20	n.d.	n.d.	n.d.	n.d.
22	SM-3	Anjihai	E2-3a	Oil sand	0.10	n.d.	n.d.	n.d.	n.d.
23	SM-4	Huoerguosi	E2-3a	Oil sand	0.20	73.40	16.00	8.80	1.20
24	SM-5	Huoerguosi	E2-3a	Oil sand	0.40	71.40	14.10	13.80	0.50
25	SM-6	Huoerguosi	E2-3a	Oil sand	1.90	71.50	13.00	6.50	2.50
26	SM-7	Huoerguosi	E2-3a	Oil sand	0.90	66.20	17.60	14.60	0.80
27	SM-8	Huoerguosi	E2-3a	Crude-oil seep	n.d.	81.90	7.90	8.20	1.50
28	SM-9	Qigu	J3q	Crude-oil seep	n.d.	64.80	12.80	12.20	4.40
29	SM-10	Qigu	J3q	Crude-oil seep	n.d.	68.80	16.00	12.20	2.20
30	SM-11	Qigu	J3q	Crude-oil seep	n.d.	64.90	10.70	10.00	4.60
31	Huo 10	3159–3170	E1-2z	Crude oil	n.d.	83.63	7.93	3.07	0.52
32	TG 1	3921	k1tg	Source rock	0.60	61.38	9.48	22.66	1.51
33	SE-1	Dalongkou	P2l	Bitumen	0.10	n.d.	n.d.	n.d.	n.d.
34	Mu 5	1300–1700	J1s	Crude oil	n.d.	83.89	5.73	3.84	0.45
35	FK 1	3647	J1s	Source rock	0.40	36.56	20.85	23.17	19.15
36	E-1	Shaqiuhe	J1b	Oil sand	2.60	27.40	3.10	44.20	17.10
37	E-2	Shaqiuhe	J1b	Oil sand	1.00	25.30	2.80	46.50	16.30
38	J251-H	4361–4976	P2l	Crude oil	n.d.	52.18	14.41	19.35	4.12
39	J174	3135	P2p	Source rock	2.48	60.53	16.32	19.55	2.67
40	J174	3314	P2l	Source rock	0.40	43.92	19.29	29.64	6.53

EOM = Extracted Organic Matter, SARA = Saturates+Aromatics+Resins+Asphaltenes; n.d. = no data.