Geochemical Characteristics of the Middle Devonian Dacaozi-Tanshanping Shale Strata in the Yanyuan Basin, Southwest China: Implications for Organic Matter Accumulation and Preservation

Table 2

Concentrations of trace elements (unit: μg/g) in samples from the Tanshanping and Dacaozi Formations in the Ninglang-Yanyuan Basin.

Sample code	Member	V	Cr	Co	Ni	Rb	Sr	Zr	Mo	Ba	Hf	U	V/Cr	Ni/Co	Th/U	V/Sc	V/(V+Ni)	Sr/Ba	Baxs	P/Ti
Q1908705	Tanshanping	15.47	7.56	1.26	7.09	9.74	208.89	10.25	2.29	26.59	0.31	6.17	2.05	5.62	0.17	6.70	0.69	7.86	26.55	0.30
Q1908706	Tanshanping	137.07	102.71	21.27	68.95	81.52	231.30	92.25	11.01	115.11	3.11	7.53	1.33	3.24	3.11	9.24	0.67	2.01	115.03	0.14
Q1908709	Tanshanping	165.26	184.98	18.04	48.76	175.08	181.33	181.43	1.38	478.90	5.76	6.79	0.89	2.70	2.92	8.32	0.77	0.38	478.78	0.14
Q1908837	Tanshanping	124.37	173.71	15.58	58.45	136.49	152.96	189.48	5.28	294.19	5.85	7.08	0.72	3.75	3.05	9.30	0.68	0.52	294.07	0.07
Q1908712	Tanshanping	56.25	63.88	5.62	19.25	43.14	551.63	55.49	0.86	68.95	1.86	2.41	0.88	3.43	3.06	7.99	0.74	8.00	68.89	0.33
Q1908713	Tanshanping	78.13	43.99	8.69	31.22	59.70	577.97	68.11	3.83	112.01	2.25	3.11	1.78	3.59	3.68	6.64	0.71	5.16	111.94	0.30
Q1908714	Tanshanping	109.32	111.71	11.31	32.65	107.96	121.50	137.41	1.52	202.22	4.17	4.23	0.98	2.89	3.50	10.05	0.77	0.60	202.11	0.11
Q1908721	Tanshanping	140.34	139.53	14.11	34.53	87.22	325.95	272.63	0.72	216.50	7.65	4.94	1.01	2.45	4.88	11.84	0.80	1.51	216.37	0.43
Q1908723	Tanshanping	135.13	137.15	16.79	42.66	104.49	579.60	126.24	1.00	264.89	3.75	4.19	0.99	2.54	3.69	11.18	0.76	2.19	264.77	0.25
Q1908727	Tanshanping	159.17	142.46	17.67	55.93	117.31	992.74	142.33	9.73	574.02	4.22	10.49	1.12	3.16	1.65	12.12	0.74	1.73	573.91	0.43
Q1908734	Tanshanping	112.28	109.49	14.55	46.75	80.03	1105.91	102.26	6.67	246.32	3.19	8.82	1.03	3.21	1.94	8.53	0.71	4.49	246.22	0.55
Q1908843	Tanshanping	69.51	68.67	7.17	31.88	50.82	1335.90	54.31	2.09	141.67	1.70	4.65	1.01	4.45	1.34	10.04	0.69	9.43	141.61	0.59
Q1908844	Tanshanping	138.81	84.27	14.16	38.81	113.76	678.97	134.54	1.89	342.83	4.30	5.39	1.65	2.74	3.14	12.11	0.78	1.98	342.71	0.37
Q1908737	Tanshanping	137.36	77.10	16.42	42.55	97.29	648.31	142.07	1.62	480.04	4.39	4.53	1.78	2.59	3.55	11.36	0.76	1.35	479.93	0.30
Q1908847	Dacaozi	141.02	139.65	18.40	40.86	122.04	560.28	181.83	1.70	622.67	5.36	5.03	1.01	2.22	4.64	9.37	0.78	0.90	622.67	0.70
Q1908742	Dacaozi	128.19	133.17	16.72	45.49	118.83	769.06	121.17	1.28	660.75	3.71	7.10	0.96	2.72	1.90	8.52	0.74	1.16	660.64	0.97
Q1908849	Dacaozi	180.03	167.36	22.38	51.96	159.87	257.43	215.42	4.00	1426.36	6.17	6.13	1.08	2.32	3.21	13.03	0.78	0.18	1426.27	0.19
Q1908745	Dacaozi	156.35	157.74	19.43	46.54	141.12	300.84	177.80	1.55	643.92	5.11	5.06	0.99	2.39	3.23	11.89	0.77	0.47	643.78	0.19
Q1908746	Dacaozi	83.54	72.78	11.57	25.03	77.00	209.36	243.36	0.71	605.66	7.13	3.67	1.15	2.16	3.80	9.20	0.77	0.35	605.53	0.26
Q1908748	Dacaozi	117.42	109.68	13.97	39.92	102.69	1169.57	125.97	1.54	1201.71	3.68	4.69	1.07	2.86	2.84	8.89	0.75	0.97	1201.58	0.20
Q1908751	Dacaozi	177.21	167.37	24.82	61.38	153.49	299.38	187.71	1.15	783.38	5.51	5.15	1.06	2.47	3.64	12.31	0.74	0.38	783.27	0.17
Q1908753	Dacaozi	95.04	91.64	10.15	31.49	71.88	864.32	72.22	0.76	484.48	2.23	3.24	1.04	3.10	2.89	10.05	0.75	1.78	484.34	0.56
Q1908756	Dacaozi	172.35	170.51	20.22	50.68	137.80	148.75	220.54	2.48	802.06	6.30	6.44	1.01	2.51	2.97	11.72	0.77	0.19	801.98	0.21
Q1908759	Dacaozi	22.65	42.21	7.48	18.67	31.21	213.97	118.14	0.76	225.70	3.71	1.52	0.54	2.50	3.18	5.62	0.55	0.95	225.56	0.61
Q1908761	Dacaozi	214.56	189.15	24.12	71.26	175.25	218.80	193.11	2.20	824.44	5.76	6.98	1.13	2.95	3.05	10.93	0.75	0.27	824.36	0.32
Q1908762	Dacaozi	118.20	114.89	13.25	29.14	116.69	124.26	252.55	0.59	766.60	7.32	4.60	1.03	2.20	3.79	9.45	0.80	0.16	766.46	0.19
Q1908765	Dacaozi	33.05	60.59	7.43	11.32	39.04	268.61	97.25	0.51	270.83	2.59	1.55	0.55	1.52	3.53	8.29	0.74	0.99	270.70	0.44
Q1908767	Dacaozi	95.96	113.46	12.11	23.15	104.28	124.51	268.45	0.57	674.62	7.57	4.35	0.85	1.91	3.79	9.31	0.81	0.18	674.53	0.20
Q1908768	Dacaozi	170.67	130.90	23.93	64.94	166.23	157.34	208.30	1.72	891.17	5.76	5.11	1.30	2.71	3.84	9.30	0.72	0.18	891.04	0.24
Q1908771	Dacaozi	175.19	93.09	23.81	44.76	159.06	166.72	281.99	0.99	855.18	7.95	6.64	1.88	1.88	3.25	9.95	0.80	0.19	855.02	0.21
Q1908775	Dacaozi	72.52	74.54	13.46	25.42	93.34	75.93	214.39	0.67	633.45	5.94	2.34	0.97	1.89	4.92	7.91	0.74	0.12	633.30	0.16
Q1908777	Dacaozi	156.78	116.68	23.30	52.99	151.86	169.14	187.90	0.99	926.44	5.36	4.69	1.34	2.27	3.94	8.94	0.75	0.18	926.31	0.12
Q1908785	Dacaozi	177.43	155.47	16.13	47.27	135.69	180.69	194.90	0.69	1648.02	5.79	5.41	1.14	2.93	3.26	15.92	0.79	0.11	1647.87	0.33
Q1908787	Dacaozi	119.68	120.84	12.59	32.08	97.13	259.97	202.79	0.60	1326.24	6.29	4.62	0.99	2.55	3.24	12.14	0.79	0.20	1326.12	0.51
Q1908789	Dacaozi	65.73	99.51	8.09	17.24	69.80	230.26	174.56	0.71	1466.94	4.38	3.85	0.66	2.13	4.40	10.89	0.79	0.16	1466.85	0.74
Q1908798	Dacaozi	165.72	81.48	27.34	56.88	156.85	282.11	187.85	1.94	928.08	5.65	8.01	2.03	2.08	2.52	9.14	0.74	0.30	927.98	0.59
Q1908800	Dacaozi	135.60	127.17	11.82	28.94	157.10	104.52	274.27	0.61	917.98	7.82	4.29	1.07	2.45	4.30	9.46	0.82	0.11	917.87	0.11
Q1908801	Dacaozi	107.37	84.22	14.21	27.74	123.22	135.11	234.60	0.55	792.74	6.88	4.12	1.27	1.95	3.92	8.93	0.79	0.17	792.60	0.40
Q1908802	Dacaozi	92.21	55.28	11.46	23.65	115.00	77.49	228.30	0.79	710.04	6.66	3.26	1.67	2.06	4.60	9.04	0.80	0.11	709.92	0.06
Q1908803	Dacaozi	158.26	76.84	18.49	41.22	149.39	161.44	222.89	1.25	1337.85	6.41	5.15	2.06	2.23	3.98	9.94	0.79	0.12	1337.72	0.32
Q1908808	Dacaozi	149.66	80.03	20.70	39.16	136.53	127.57	250.59	0.80	788.96	7.24	5.22	1.87	1.89	3.38	12.11	0.79	0.16	788.83	0.34
Q1908811	Dacaozi	139.47	116.24	54.07	110.28	105.93	369.09	191.94	2.05	778.83	5.38	6.94	1.20	2.04	2.10	7.35	0.56	0.47	778.70	1.09
Q1908814	Dacaozi	187.22	148.38	18.14	43.63	161.81	120.21	218.69	0.86	809.75	6.54	5.64	1.26	2.40	3.52	11.09	0.81	0.15	809.66	1.98
Q1908817	Dacaozi	143.57	76.71	20.77	60.50	136.56	188.79	167.92	2.69	778.06	4.85	4.71	1.87	2.91	4.37	8.73	0.70	0.24	777.91	(0.00)
Q1908819	Dacaozi	141.27	72.12	16.49	50.50	122.50	146.01	195.70	2.37	783.05	5.80	4.22	1.96	3.06	3.50	11.40	0.74	0.19	782.98	0.61
Q1908823	Dacaozi	128.65	70.10	16.29	50.09	123.92	154.75	256.60	1.82	646.15	7.47	4.76	1.84	3.07	3.48	9.67	0.72	0.24	646.02	(0.00)
Q1908825	Dacaozi	198.05	156.91	31.41	73.86	177.88	112.78	191.43	1.56	804.79	5.64	6.11	1.26	2.35	3.09	11.62	0.73	0.14	804.66	0.37
Q1908826	Dacaozi	191.23	157.70	27.62	61.27	181.75	101.74	164.83	1.37	907.78	4.95	5.24	1.21	2.22	3.38	11.37	0.76	0.11	907.65	0.22
Q1908828	Dacaozi	205.39	135.73	23.93	50.51	179.94	116.77	201.04	1.30	861.98	6.04	6.19	1.51	2.11	3.25	10.90	0.80	0.14	861.85	0.27
Q1908832	Dacaozi	181.81	76.41	22.08	45.95	157.33	110.49	191.07	0.69	1105.79	5.93	5.24	2.38	2.08	3.32	11.96	0.80	0.10	1105.66	0.33
Q1908835	Dacaozi	196.25	78.93	13.50	43.94	156.97	189.10	157.81	0.34	994.91	4.86	8.70	2.49	3.26	1.89	11.42	0.82	0.19	994.78	0.80