Origin and genetic mechanism of hydrocarbon gas sources of the highly saturated gas hydrate deposits in the northern South China Sea

doi:10.13745/j.esf.sf.2024.6.53

Abstract

Abstract:

The origin of hydrocarbon gas is crucial for clarifying the formation and accumulation mechanisms of natural gas hydrate. Many highly saturated natural gas hydrate deposits have been drilled in the northern South China Sea. However, the source and genetic mechanism of hydrocarbon gases have not been systematically elucidated, significantly restricting the identification of main gas sources and the deployment of future exploration strategies. In this study, taking the typical highly saturated gas hydrate deposits in the Qiongdongnan and Shenhu areas as examples, the source and genetic mechanism of hydrocarbon gases are systematically investigated using an integrated approach that includes gas geochemistry, sediment organic geochemistry, geomicrobiology, and seismic interpretation. The results show that the genetic types of hydrate gases in the northern South China Sea are diverse, including primary and secondary microbial gases, as well as thermogenic coal-type and oil-type gases. Notably, the thermogenic gases within different gas hydrate deposits have undergone microbial degradation and modification to varying extents: Shenhu W11-17 gas hydrate deposit>Shenhu W18-19 gas hydrate deposit>Qiongdongnan GMGS5-W08 gas hydrate deposit. The hydrate gas source layer consists of a shallowly buried microbial gas source layer (20-85 ℃) and a deeply buried thermogenic gas source layer (vitrinite reflectance R_o>0.5%). The upper part of the microbial gas source layer (<300 mbsf), which has been drilled and sampled, shows relatively low gas generative potential. In contrast, the thermogenic gas source represents great gas generative potential due to the existence of effective source kitchens and gas-prone coal-type source rocks in the mature stage. The deeply buried thermogenic source kitchen, conventional hydrocarbon deposits, shallowly buried microbial gas source layer, and composite gas migration conduits (including depression-controlled faults, gas chimneys, tubular seeps, and microfractures) constitute the hydrocarbon gas supply system for the highly saturated gas hydrate deposits in the northern South China Sea. The contribution of the deeply buried thermogenic source kitchen is extremely critical for the large-scale accumulation of gas hydrate. However, most of the thermogenic gases transported through the microbial gas source layer undergo severe microbial degradation and are ultimately converted into secondary microbial methane for gas hydrate mineralization. There are three major pathways for hydrocarbon gases in the highly saturated hydrate deposits of the northern South China Sea:(1)Hydrate gases directly originating from the deeply buried thermogenic gas source kitchen, i.e., non-biodegraded thermogenic gas. (2)Hydrate gases derived from secondary microbial gases, which are generated by anaerobic methanogenesis degradation processes after deeply buried thermogenic hydrocarbons migrate into the microbial gas source layer.(3)Hydrate gases supplied by primary microbial gases, which are generated by microbial utilization of in-situ sediment organic matter in the shallowly buried microbial gas source layer.

Key words: secondary microbial gas, gas origin, hydrate gas supply system, accumulation mechanism, natural gas hydrate

CLC Number:

P618.13

LAI Hongfei, KUANG Zenggui, FANG Yunxin, XU Chenlu, REN Jinfeng, LIANG Jinqiang, LU Jing’an. Origin and genetic mechanism of hydrocarbon gas sources of the highly saturated gas hydrate deposits in the northern South China Sea[J]. Earth Science Frontiers, 2025, 32(2): 36-60.

Figures/Tables 16

References 75

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矿藏/气体类型	井号	深度 (bsf)/m	样品类型	气体组分含量				C₁/ (C₂+C₃)	碳同位素组成δ¹³C/‰					甲烷氢同位素组成δD₁/‰	数据来源文献
矿藏/气体类型	井号	深度 (bsf)/m	样品类型	C₁含量/ %	C₂含量/ %	C₃含量/ 10^-6	C₃₊含量/ 10^-6	C₁/ (C₂+C₃)	C₁	C₂	C₃	nC₄	nC₅	甲烷氢同位素组成δD₁/‰	数据来源文献
W11-17 矿藏	W17D	250.2	PCS	98.45	1.47	768	—	64	-59.7	-32.3	-18.5	—	—	-170.5	本文
	W17D	259.35	PCS	98.89	0.80	3 045	—	89	-60.8	-32.6	-18.2	—	—	-164
	W17D	263.02	PCS	98.86	0.84	2 961	—	87	-56.7	-32.8	-18.3	—	—	-165.2
	W17D	257.00	PCS	98.94	0.77	2 864	—	93	-58.7	-32.7	-18.2	—	—	-164.5
	SH-W04	208.1	PCS	99.35	0.51	1 337	78	153	-66.2	-33.2	-19.7	-21.2	—	-176.1
	SH-W04	210.4	PCS	99.51	0.44	360	35	205	-65.4	-33.3	-19.4	—	—	-177.5
	SH-W02	259.1	PCS	99.48	0.43	356	76	201	-65.2	-33.6	-22.3	-23.1	-25.7	-178.2
	SH-W02	266.8	PCS	99.52	0.39	670	241	212	-66.0	-33.7	-21.7	-23.2	-25.3	-175.1
	SC3	135.25	PCS	99.7	0.25	10	0	399	-66.4	—	—	—	—	-189.5	[34]
		149.34	VG	99.6	0.31	90	131	311	-64.9	—	—	—	—	-185.4
		153.71	VG	99.3	0.34	1 784	1 211	193	-65.2	—	—	—	—	-185
		161.10	PCS	99.6	0.42	74	0	231	-65.4	—	—	—	—	-181.3
		161.20	VG	99.6	0.39	72	0	252	-64.7	—	—	—	—	-185.6
		170.34	VG	99.5	0.5	88	0	195	-65.4	—	—	—	—	-162.2
		174.41	VG	99.4	0.55	88	0	179	-64.6	—	—	—	—	-184.6
		177.40	PCS	99.4	0.61	82	0	161	-64.6	—	—	—	—	-185.4
		199.98	VG	99.5	0.5	132	0	194	-64.6	—	—	—	—	-181.2
	SH-W02	209.4~209.62	PCS	99.45	0.5	211	33	191	-66.5	-32.2	-18.2	—	—	n.g.	[40]
	SC3	136.57	HG	99.66	0.31	20	0	317	-65.2	—	—	—	—	-191.3	[35]
	SH-W04	197.5	PCS	99.07	0.66	2 408	308	110	-66.0	-32.8	-20.0	-20.9	—	-175.6	[40]
W18-19 矿藏	SC1	155.48	HG	99.6	0.098	1 780	780	360	-47.4	—	—	—	—	-172.6	[57]
		162.16	HG	99.2	0.647	1 090	750	131	-47.1	—	—	—	—	-174.1
		162.90	HG	99.1	0.674	1 090	850	126	-47.7	—	—	—	—	-177.7
		170.00	HG	98.9	0.756	2 160	950	102	-47.8	—	—	—	—	-173.2
	SC1	155.24	PCS	98.0	0.09	1 436	447	422	-47.4	—	—	—	—	-172.6	[34]
	SC1	162.94	VG	98.5	1.03	3 437	837	72	-46.4	—	—	—	—	-164.7
	SC1	169.19	VG	98.6	1.11	1 495	570	78	-47.6	—	—	—	—	-170
	SC1	170.00	PCS	98.9	0.78	1 976	861	102	-47.8	—	—	—	—	-173.2
	SC2	149.26	PCS	98.7	0.53	686	468	164	-46.4	—	—	—	—	-174.5
	SC2	149.61	PCS	99.2	0.7	371	181	134	-47.3	—	—	—	—	-177.4
	SC2	153.69	VG	98.4	1.18	3 827	504	63	-46.2	—	—	—	—	-185.0
	SC2	157.41	PCS	98.5	0.79	5 281	1 585	75	-47.2	—	—	—	—	-171.3
	SC2	165.91	VG	98.1	1.82	847	110	52	-45.8	—	—	—	—	-170.1
	SC2	170.26	PCS	98.4	1.31	2 505	778	63	-46.8	—	—	—	—	-182.5
	SC1	155.35~155.48	HG	99.76	0.17	666	103	426	-49.5	-27.8	-19.4	-24.7	—	-165.4	[41]
	SC1	160.02~160.13	HG	99.36	0.61	257	0	156	-48.9	-26.9	-16.5	—	—	-179.6
	SC1	160.58~160.76	HG	99.32	0.43	1 124	300	183	-49.1	-26.1	-19.2	-26.4	—	-163.3
	SC1	161.43~161.63	HG	98.55	1.15	2 278	574	72	-49.5	-25.2	-18.7	—	—	-174.5
	SC1	163.25~163.46	HG	99.10	0.79	780	222	115	-50.2	-25.7	-18.3	—	—	-169.0
	SC2	158.69~158.84	HG	99.22	0.68	202	68	142	-47.4	-22.7	-17.4	—	—	-172.5
	SC2	169.85~170.08	HG	98.60	1.37	238	61	71	-47.5	-24.0	-17.0	—	—	-178.7
	SC1	155.48	HG	99.63	0.22	1 078	161	302	-47.0	-30.5	-18.3	-16.4	—	-190.7	[35]
	SC1	160.76	HG	99.07	0.76	640	145	120	-49.2	-28.9	-18.6	-18.5	—	-195.0
	SC1	161.63	HG	98.17	1.52	1 996	542	57	-47.8	-28.9	-17.9	-15.2	—	-196.6
	SC1	162.16	HG	98.69	1.17	612	145	80	-47.6	-27.6	-17.2	-18.2	—	-191.2
	SC1	163.46	HG	98.60	1.25	618	254	75	-48.1	-28.7	-18.3	-20.4	—	-191.9
	SC2	144.52	HG	99.60	0.25	1 130	132	276	-46.2	-28.6	-18.1	-17.4	—	-191.9
	SC2	158.84	HG	98.22	1.58	570	74	60	-47.3	-28.3	-18.0	—	—	-197.9
	SC2	170.08	HG	98.25	1.64	569	104	58	-46.9	-27.7	-17.3	-17.2	—	-193.5
GMGS- W08 矿藏	W08C	8.00	HG	97.69	2.05	500	231	47	-59.5	-26.0	-22.4	—	—	-187	[37]
	W08B	32.88	PCS	94.94	4.23	5 800	2 172	20	-54.4	-25.5	-22.9	—	—	-185
	W08B	62.93	HG	81.21	12.88	45 800	12 471	5	-56.3	-26.9	-22.7	—	—	-176
	W08B	79.00	PCS	95.75	3.69	3 900	1 681	24	-58.6	-25.1	-21.6	—	—	-170
	W08B	80.90	PCS	95.73	3.68	3 600	1 758	24	-48.7	-22.4	-20.2	—	—	—
	W08B	112.30	PCS	96.46	2.99	3 300	1 587	29	-53.8	-23.3	-20.7	—	—	-175
	W08C	145.65	PCS	83.49	11.61	39 300	9 417	5	-49.3	-27.5	-23.0	—	—	—
	W08C	148.40	HG	79.16	14.4	51 500	12 416	4	-50.4	-26.5	-22.8	—	—	—
	W08C	158.00	PCS	84.17	10.99	39 000	9 123	6	-50.4	-26.9	-22.2	—	—	-183
	W08C	187.10	PCS	92.82	4.56	20 700	4 932	14	-50.4	-26.7	-23.2	—	—	-180
	W08B	17.07	HG	96.95	2.6	3 064	n.g.	33	-57.6	-25.1	-20.6	-21.5	—	-169
	W08B	60.00	HG	96.07	3.1	4 977	n.g.	27	-60.9	-25.9	-21.4	-22.4	—	-181
	W08B	63.58	HG	89.45	7.77	20 730	n.g.	9	-57.3	-26.3	-21.9	—	—	-179
	W08B	63.18	HG	96.20	3.3	3 897	n.g.	26	-54.6	-22.0	—	—	—	-178
	W08B	69.35	HG	91.63	5.86	20 333	n.g.	12	-60.5	-26.2	-19.6	—	—	-183
生物成因气	SH-W20A	65.64	VG	96	0.1	478	237	2 009	-74.9	-33.8	-17.4	—	—	-174	[40]
	SH-W20A	90.34	VG	97	0.1	534	352	1 817	-70.2	-33.0	-17.0	-23.3	—	-170	[40]
	GMGS5-W01	49.27	PCS	99.59	0.29	1 245	0	255	-80.6	-29.8	-23.1	—	—	-187	[37]
	GMGS5-W01	125.80	PCS	99.81	0.15	419	0	525	-79.0	-36.1	-24.1	—	—	-180
	GMGS6-W03	27.71	VG	99.32	0.06	—	0	1 655	-77.6	-28.1	—	—	—	-178
热解成因气	LW3-1气藏	3 144.5		n.g.	n.g.	n.g.	n.g.	12	-36.6	-29.1	-27.4	-27.0	-26.6	-158.4	[58]
	LW3-1气藏	3 189.5		n.g.	n.g.	n.g.	n.g.	13	-36.8	-28.9	-27.5	-27.4	-27.2	-155.8
	LW3-1气藏	3 499.5		n.g.	n.g.	n.g.	n.g.	12	-36.6	-29.6	-29.1	-28.2	-26.2	-175.6
	L18-1气藏	2 819.9~2 846.7	DST	93.17	6.15	n.g.	n.g.	15	-40.5	-25.2	-23.8	-22.7	—	—	[59]
	L18-1气藏	2 819.9~2 846.7	DST	n.g.	n.g.	n.g.	n.g.	15	-40.4	-25.2	-23.8	—	—	—
	L18-1气藏	2 819.9~2 846.7	DST	n.g.	n.g.	n.g.	n.g.	26	-42.8	-26.2	-25.6	—	—	—

矿藏/气体类型	井号	深度 (bsf)/m	样品类型	气体组分含量				C₁/ (C₂+C₃)	碳同位素组成δ¹³C/‰					甲烷氢同位素组成δD₁/‰	数据来源文献
矿藏/气体类型	井号	深度 (bsf)/m	样品类型	C₁含量/ %	C₂含量/ %	C₃含量/ 10^-6	C₃₊含量/ 10^-6	C₁/ (C₂+C₃)	C₁	C₂	C₃	nC₄	nC₅	甲烷氢同位素组成δD₁/‰	数据来源文献
W11-17 矿藏	W17D	250.2	PCS	98.45	1.47	768	—	64	-59.7	-32.3	-18.5	—	—	-170.5	本文
	W17D	259.35	PCS	98.89	0.80	3 045	—	89	-60.8	-32.6	-18.2	—	—	-164
	W17D	263.02	PCS	98.86	0.84	2 961	—	87	-56.7	-32.8	-18.3	—	—	-165.2
	W17D	257.00	PCS	98.94	0.77	2 864	—	93	-58.7	-32.7	-18.2	—	—	-164.5
	SH-W04	208.1	PCS	99.35	0.51	1 337	78	153	-66.2	-33.2	-19.7	-21.2	—	-176.1
	SH-W04	210.4	PCS	99.51	0.44	360	35	205	-65.4	-33.3	-19.4	—	—	-177.5
	SH-W02	259.1	PCS	99.48	0.43	356	76	201	-65.2	-33.6	-22.3	-23.1	-25.7	-178.2
	SH-W02	266.8	PCS	99.52	0.39	670	241	212	-66.0	-33.7	-21.7	-23.2	-25.3	-175.1
	SC3	135.25	PCS	99.7	0.25	10	0	399	-66.4	—	—	—	—	-189.5	[34]
		149.34	VG	99.6	0.31	90	131	311	-64.9	—	—	—	—	-185.4
		153.71	VG	99.3	0.34	1 784	1 211	193	-65.2	—	—	—	—	-185
		161.10	PCS	99.6	0.42	74	0	231	-65.4	—	—	—	—	-181.3
		161.20	VG	99.6	0.39	72	0	252	-64.7	—	—	—	—	-185.6
		170.34	VG	99.5	0.5	88	0	195	-65.4	—	—	—	—	-162.2
		174.41	VG	99.4	0.55	88	0	179	-64.6	—	—	—	—	-184.6
		177.40	PCS	99.4	0.61	82	0	161	-64.6	—	—	—	—	-185.4
		199.98	VG	99.5	0.5	132	0	194	-64.6	—	—	—	—	-181.2
	SH-W02	209.4~209.62	PCS	99.45	0.5	211	33	191	-66.5	-32.2	-18.2	—	—	n.g.	[40]
	SC3	136.57	HG	99.66	0.31	20	0	317	-65.2	—	—	—	—	-191.3	[35]
	SH-W04	197.5	PCS	99.07	0.66	2 408	308	110	-66.0	-32.8	-20.0	-20.9	—	-175.6	[40]
W18-19 矿藏	SC1	155.48	HG	99.6	0.098	1 780	780	360	-47.4	—	—	—	—	-172.6	[57]
		162.16	HG	99.2	0.647	1 090	750	131	-47.1	—	—	—	—	-174.1
		162.90	HG	99.1	0.674	1 090	850	126	-47.7	—	—	—	—	-177.7
		170.00	HG	98.9	0.756	2 160	950	102	-47.8	—	—	—	—	-173.2
	SC1	155.24	PCS	98.0	0.09	1 436	447	422	-47.4	—	—	—	—	-172.6	[34]
	SC1	162.94	VG	98.5	1.03	3 437	837	72	-46.4	—	—	—	—	-164.7
	SC1	169.19	VG	98.6	1.11	1 495	570	78	-47.6	—	—	—	—	-170
	SC1	170.00	PCS	98.9	0.78	1 976	861	102	-47.8	—	—	—	—	-173.2
	SC2	149.26	PCS	98.7	0.53	686	468	164	-46.4	—	—	—	—	-174.5
	SC2	149.61	PCS	99.2	0.7	371	181	134	-47.3	—	—	—	—	-177.4
	SC2	153.69	VG	98.4	1.18	3 827	504	63	-46.2	—	—	—	—	-185.0
	SC2	157.41	PCS	98.5	0.79	5 281	1 585	75	-47.2	—	—	—	—	-171.3
	SC2	165.91	VG	98.1	1.82	847	110	52	-45.8	—	—	—	—	-170.1
	SC2	170.26	PCS	98.4	1.31	2 505	778	63	-46.8	—	—	—	—	-182.5
	SC1	155.35~155.48	HG	99.76	0.17	666	103	426	-49.5	-27.8	-19.4	-24.7	—	-165.4	[41]
	SC1	160.02~160.13	HG	99.36	0.61	257	0	156	-48.9	-26.9	-16.5	—	—	-179.6
	SC1	160.58~160.76	HG	99.32	0.43	1 124	300	183	-49.1	-26.1	-19.2	-26.4	—	-163.3
	SC1	161.43~161.63	HG	98.55	1.15	2 278	574	72	-49.5	-25.2	-18.7	—	—	-174.5
	SC1	163.25~163.46	HG	99.10	0.79	780	222	115	-50.2	-25.7	-18.3	—	—	-169.0
	SC2	158.69~158.84	HG	99.22	0.68	202	68	142	-47.4	-22.7	-17.4	—	—	-172.5
	SC2	169.85~170.08	HG	98.60	1.37	238	61	71	-47.5	-24.0	-17.0	—	—	-178.7
	SC1	155.48	HG	99.63	0.22	1 078	161	302	-47.0	-30.5	-18.3	-16.4	—	-190.7	[35]
	SC1	160.76	HG	99.07	0.76	640	145	120	-49.2	-28.9	-18.6	-18.5	—	-195.0
	SC1	161.63	HG	98.17	1.52	1 996	542	57	-47.8	-28.9	-17.9	-15.2	—	-196.6
	SC1	162.16	HG	98.69	1.17	612	145	80	-47.6	-27.6	-17.2	-18.2	—	-191.2
	SC1	163.46	HG	98.60	1.25	618	254	75	-48.1	-28.7	-18.3	-20.4	—	-191.9
	SC2	144.52	HG	99.60	0.25	1 130	132	276	-46.2	-28.6	-18.1	-17.4	—	-191.9
	SC2	158.84	HG	98.22	1.58	570	74	60	-47.3	-28.3	-18.0	—	—	-197.9
	SC2	170.08	HG	98.25	1.64	569	104	58	-46.9	-27.7	-17.3	-17.2	—	-193.5
GMGS- W08 矿藏	W08C	8.00	HG	97.69	2.05	500	231	47	-59.5	-26.0	-22.4	—	—	-187	[37]
	W08B	32.88	PCS	94.94	4.23	5 800	2 172	20	-54.4	-25.5	-22.9	—	—	-185
	W08B	62.93	HG	81.21	12.88	45 800	12 471	5	-56.3	-26.9	-22.7	—	—	-176
	W08B	79.00	PCS	95.75	3.69	3 900	1 681	24	-58.6	-25.1	-21.6	—	—	-170
	W08B	80.90	PCS	95.73	3.68	3 600	1 758	24	-48.7	-22.4	-20.2	—	—	—
	W08B	112.30	PCS	96.46	2.99	3 300	1 587	29	-53.8	-23.3	-20.7	—	—	-175
	W08C	145.65	PCS	83.49	11.61	39 300	9 417	5	-49.3	-27.5	-23.0	—	—	—
	W08C	148.40	HG	79.16	14.4	51 500	12 416	4	-50.4	-26.5	-22.8	—	—	—
	W08C	158.00	PCS	84.17	10.99	39 000	9 123	6	-50.4	-26.9	-22.2	—	—	-183
	W08C	187.10	PCS	92.82	4.56	20 700	4 932	14	-50.4	-26.7	-23.2	—	—	-180
	W08B	17.07	HG	96.95	2.6	3 064	n.g.	33	-57.6	-25.1	-20.6	-21.5	—	-169
	W08B	60.00	HG	96.07	3.1	4 977	n.g.	27	-60.9	-25.9	-21.4	-22.4	—	-181
	W08B	63.58	HG	89.45	7.77	20 730	n.g.	9	-57.3	-26.3	-21.9	—	—	-179
	W08B	63.18	HG	96.20	3.3	3 897	n.g.	26	-54.6	-22.0	—	—	—	-178
	W08B	69.35	HG	91.63	5.86	20 333	n.g.	12	-60.5	-26.2	-19.6	—	—	-183
生物成因气	SH-W20A	65.64	VG	96	0.1	478	237	2 009	-74.9	-33.8	-17.4	—	—	-174	[40]
	SH-W20A	90.34	VG	97	0.1	534	352	1 817	-70.2	-33.0	-17.0	-23.3	—	-170	[40]
	GMGS5-W01	49.27	PCS	99.59	0.29	1 245	0	255	-80.6	-29.8	-23.1	—	—	-187	[37]
	GMGS5-W01	125.80	PCS	99.81	0.15	419	0	525	-79.0	-36.1	-24.1	—	—	-180
	GMGS6-W03	27.71	VG	99.32	0.06	—	0	1 655	-77.6	-28.1	—	—	—	-178
热解成因气	LW3-1气藏	3 144.5		n.g.	n.g.	n.g.	n.g.	12	-36.6	-29.1	-27.4	-27.0	-26.6	-158.4	[58]
	LW3-1气藏	3 189.5		n.g.	n.g.	n.g.	n.g.	13	-36.8	-28.9	-27.5	-27.4	-27.2	-155.8
	LW3-1气藏	3 499.5		n.g.	n.g.	n.g.	n.g.	12	-36.6	-29.6	-29.1	-28.2	-26.2	-175.6
	L18-1气藏	2 819.9~2 846.7	DST	93.17	6.15	n.g.	n.g.	15	-40.5	-25.2	-23.8	-22.7	—	—	[59]
	L18-1气藏	2 819.9~2 846.7	DST	n.g.	n.g.	n.g.	n.g.	15	-40.4	-25.2	-23.8	—	—	—
	L18-1气藏	2 819.9~2 846.7	DST	n.g.	n.g.	n.g.	n.g.	26	-42.8	-26.2	-25.6	—	—	—

水合物矿藏	站位	深度(bsf)/ m	TOC 含量/%	数据来源文献	水合物矿藏	站位	深度(bsf)/ m	TOC 含量/%	数据来源文献
神狐 W11-17 矿藏	W17D	1.58	0.88	本文	神狐 W18-19 矿藏	SC2	113.17	0.24	[41]
	W17D	4.76	0.75			SC2	115.19	0.3
	W17D	12.73	0.66			SC2	115.35	0.24
	W17D	17.87	0.57			SC2	115.42	0.27
	W17D	19.73	0.39			SC2	118.72	0.18
	W17D	20.67	0.39			SC2	120.175	0.21
	W17D	191.27	0.15			SC2	120.92	0.18
	W17D	228.96	0.16			SC2	121.59	0.21
	W17D	250.29	0.22			SC2	125.39	0.12
	W17D	262.83	0.15			SC2	128.065	0.13
	SC3	49.71	0.17			SC2	130.44	0.14
	SC3	93.15	0.19			SC2	130.06	0.13
	SC3	132.79	0.21			SC2	132.86	0.18
	SC3	147.19	0.24			SC2	136.235	0.14
	SC3	171.97	0.22			SC2	136.29	0.15
	SC3	206.97	0.27			SC2	135.74	0.11
	SC3	298.25	0.25			SC2	137.83	0.14
琼东南 GMGS5- W08 矿藏	QDN-W08	3.02	0.46	[36]		SC2	140.71	0.16
	QDN-W08	8.95	0.56			SC2	143.17	0.17
	QDN-W08	18.06	0.66			SC2	149.94	0.18
	QDN-W08	27.205	0.47			SC2	152.64	0.18
	QDN-W08	53.015	0.47			SC2	153.69	0.16
	QDN-W08	54.65	0.41			SC2	158.23	0.16
	QDN-W08	63.25	0.43			SC2	161.06	0.15
	QDN-W08	81.50	0.29			SC2	163.34	0.15
	QDN-W08	115.225	0.35			SC2	164.39	0.13
	QDN-W08	168.1	0.33			SC2	168.63	0.18
神狐 W18-19 矿藏	SC2	39.46	0.89	本文		SC2	169.83	0.17
	SC2	47.08	0.73			SC2	170.51	0.17
	SC2	82.72	0.44			SC2	177.56	0.17
	SC2	84.67	0.45			SC2	179.85	0.18
	SC2	95.09	0.55			SC2	180.25	0.19
	SC2	98.88	0.47			SC2	185.39	0.23
	SC2	101.54	0.37			SC2	185.44	0.18
	SC2	101.61	0.37			SC2	188.32	0.18
	SC2	105.30	0.29			SC2	189.10	0.17
	SC2	108.30	0.25			SC2	189.56	0.19
	SC2	110.23	0.19	[41]		SC2	189.62	0.21
	SC2	110.57	0.26			SC2	190.18	0.21
	SC2	110.65	0.21

水合物矿藏	站位	深度(bsf)/ m	TOC 含量/%	数据来源文献	水合物矿藏	站位	深度(bsf)/ m	TOC 含量/%	数据来源文献
神狐 W11-17 矿藏	W17D	1.58	0.88	本文	神狐 W18-19 矿藏	SC2	113.17	0.24	[41]
	W17D	4.76	0.75			SC2	115.19	0.3
	W17D	12.73	0.66			SC2	115.35	0.24
	W17D	17.87	0.57			SC2	115.42	0.27
	W17D	19.73	0.39			SC2	118.72	0.18
	W17D	20.67	0.39			SC2	120.175	0.21
	W17D	191.27	0.15			SC2	120.92	0.18
	W17D	228.96	0.16			SC2	121.59	0.21
	W17D	250.29	0.22			SC2	125.39	0.12
	W17D	262.83	0.15			SC2	128.065	0.13
	SC3	49.71	0.17			SC2	130.44	0.14
	SC3	93.15	0.19			SC2	130.06	0.13
	SC3	132.79	0.21			SC2	132.86	0.18
	SC3	147.19	0.24			SC2	136.235	0.14
	SC3	171.97	0.22			SC2	136.29	0.15
	SC3	206.97	0.27			SC2	135.74	0.11
	SC3	298.25	0.25			SC2	137.83	0.14
琼东南 GMGS5- W08 矿藏	QDN-W08	3.02	0.46	[36]		SC2	140.71	0.16
	QDN-W08	8.95	0.56			SC2	143.17	0.17
	QDN-W08	18.06	0.66			SC2	149.94	0.18
	QDN-W08	27.205	0.47			SC2	152.64	0.18
	QDN-W08	53.015	0.47			SC2	153.69	0.16
	QDN-W08	54.65	0.41			SC2	158.23	0.16
	QDN-W08	63.25	0.43			SC2	161.06	0.15
	QDN-W08	81.50	0.29			SC2	163.34	0.15
	QDN-W08	115.225	0.35			SC2	164.39	0.13
	QDN-W08	168.1	0.33			SC2	168.63	0.18
神狐 W18-19 矿藏	SC2	39.46	0.89	本文		SC2	169.83	0.17
	SC2	47.08	0.73			SC2	170.51	0.17
	SC2	82.72	0.44			SC2	177.56	0.17
	SC2	84.67	0.45			SC2	179.85	0.18
	SC2	95.09	0.55			SC2	180.25	0.19
	SC2	98.88	0.47			SC2	185.39	0.23
	SC2	101.54	0.37			SC2	185.44	0.18
	SC2	101.61	0.37			SC2	188.32	0.18
	SC2	105.30	0.29			SC2	189.10	0.17
	SC2	108.30	0.25			SC2	189.56	0.19
	SC2	110.23	0.19	[41]		SC2	189.62	0.21
	SC2	110.57	0.26			SC2	190.18	0.21
	SC2	110.65	0.21

水合物矿藏	钻探站位	深度(bsf)/ m	泥质含量/%	氯仿沥青“A” 含量/(mg·g^-1)	饱和烃含量/%	芳烃含量/%	非烃含量/%	沥青质含量/%	数据来源文献
神狐W11-17 矿藏	W17D	229.02	22.77	0.09	13.33	13.94	18.79	53.94	本文
神狐W11-17 矿藏	W17D	250.36	25.26	0.07	17.24	22.41	13.79	46.55	本文
神狐W18-19 矿藏	SC2	149.46~152.46	18.74	0.20	4.71	0.67	7.40	87.22	本文
	SC2	158.3~163.34	19.31	0.24	8.55	1.14	8.55	81.77
	SC2	168.59~170.55	22.78	0.15	24.75	1.98	11.88	61.39
琼东南GMGS5-W08 矿藏	GMGS-W08	81.45~81.55	19.81	0.26	2.65	2.65	9.93	84.77	[36]
琼东南GMGS5-W08 矿藏	GMGS-W08	115.16~115.29	28.15	0.31	3.29	3.29	15.13	78.29	[36]