Reconstruction of the Cenozoic History of Hydrocarbon Fluids from Rifting Stage to Passive Continental Margin Stage in the Huizhou Sag, the Pearl River Mouth Basin

Table 1

The percentage of argillaceous source rock in the Huizhou Sag (HZS).

Formation	Well	Systems tracts	Depth (m)	Facies	Percentage (%)
Eocene Wenchang	132	TST	3140–3280	Deep lacustrine	82.5
	241	TST	3601–3776	Fluvial	15.3
	243	TST	4013.5–4124	Shore-shallow lacustrine	62.7
	211	TST	4228–4456	Shore-shallow lacustrine	41.1
Eocene Enping	211	HST	3646–3811.07	Fluvial-delta	7.7
		TST	3811.07–4228	Swamp	14.7
	243	TST	3445–4130	Shore-shallow lacustrine	31.1
	181	HST	2919.5–3128	Fluvial-delta	29.5
	142	HST	2836.5–3155	Shore-shallow lacustrine	29.9
		TST	3155–3551	Fluvial-delta	20.6
	131	HST	2820–3078.4	Shore-shallow lacustrine	22.8
		TST	3078.4–3193	Fluvial-delta	15.1
	232	HST	3734.85–3969.02	Fluvial-delta	30.4
		TST	3969.02–4520	Shore-shallow lacustrine	23.7
		TST	3128–3254	Fluvial-delta	13.4
	131	HST	3805–4339.07	Swamp	33.3
		TST	4339.07–4804	Shore-shallow lacustrine	18.8
	81	HST	3170.5–3485.77	Delta	36.5
		TST	3485.77–3810.8	Delta	24.1
		LST	3810.8–4583	Fluvial	13.2
	231	HST	3646–3953.12	Fluvial-delta	25.7
		TST	3953.12–4250	Shore-shallow lacustrine	15
	132	HST	2848–3060	Fluvial-delta	40.8
		TST	3060–3140.05	Fluvial-delta	16.7

LST: lowstand systems tract; TST: transgression systems tract; HTS: highstand systems tract. Note. Lithology data came from core analysis and cuttings logging.