Geochronology, Geochemistry and Tectonic Significance of Linzizong Group Volcanic Rocks in the Nimu-Jiacha Area, Eastern Lhasa Block,Tibet,China

doi:10.19657/j.geoscience.1000-8527.2019.04.03

Abstract

Abstract:

Lhasa block is featured by extensive Mesozoic-Cenozoic magmatism, which is important for understanding the Neo-Tethyan evolution and the tectonic history of the Tibetan plateau. In this paper, LA-ICP-MS zircon U-Pb dating and whole-rock geochemical analyses of the Bima Formation volcanic rocks in the Nimu-Jiacha area (eastern Lhasa block) were carried out. Zircon U-Pb ages of the Bima Formation volcanic rock are about 55.2-57.6 Ma, which are significantly younger than the published Pima volcanic rock age of 177-195 Ma, and are coeval with the Linzizong Group volcanic rocks (30.4-70.0 Ma). Accordingly, the Bima Formation that was originally thought to be in the area should be redefined as Nianbo Formation of the Linzizong Group. The main volcanic rocks in the study area are basalt, basaltic andesite, andesite and dacite, belonging to the middle-to high-K calc-alkaline series. The volcanic rocks are enriched in LILEs (e.g., Rb, Th, U) and show clear negative anomalies of HFSEs (e.g., Nb, Ta, Zr, Ti), with typical island arc geochemical affinities. The REE patterns reveal LREE enrichments, and no or moderately-negative Eu anomaly. In addition, the Nianbo Formation volcanic rocks in the study area are younger than the Nianbo Formation in the middle-western Lhasa block. Combined with published information, it is indicated that the India-Asia collision progressed from west to east.

Key words: zircon LA-ICP-MS U-Pb dating, geochemistry, Nianbo Formation, Linzizong Group, Lhasa block

CLC Number:

P588.1

WEI Tianwei, YANG Feng, KANG Zhiqiang, WEI Naishao, LIU Di, CAO Yan, LI Daixian, CHEN Huan, CHEN Linhua. Geochronology, Geochemistry and Tectonic Significance of Linzizong Group Volcanic Rocks in the Nimu-Jiacha Area, Eastern Lhasa Block,Tibet,China[J]. Geoscience, 2019, 33(04): 715-726.

Figures/Tables 10

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分析点号	含量/10^-6			Th/U	同位素比值					年龄/Ma
分析点号	Th	U		Th/U	²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ		²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ
14BM-07-01	2 079	2 427	0.86		0.062 00	0.003 41	0.008 65	0.000 19	61.1		3.3	55.5	1.2
14BM-07-02	280	422	0.66		0.086 92	0.007 74	0.009 73	0.000 23	84.6		7.2	62.4	1.5
14BM-07-03	427	494	0.86		0.070 90	0.004 46	0.009 04	0.000 17	69.6		4.2	58.0	1.1
14BM-07-04	351	406	0.86		0.059 33	0.004 55	0.007 55	0.000 26	58.5		4.4	48.5	1.6
14BM-07-05	744	551	1.35		0.063 44	0.005 98	0.008 00	0.000 26	62.5		5.7	51.3	1.6
14BM-07-06	238	383	0.62		0.082 43	0.005 94	0.008 95	0.000 18	80.4		5.6	57.4	1.1
14BM-07-07	2 066	5 051	0.41		0.029 61	0.001 15	0.004 87	0.000 06	29.6		1.1	31.3	0.4
14BM-07-08	397	426	0.93		0.064 99	0.004 11	0.008 20	0.000 17	63.9		3.9	52.6	1.1
14BM-07-09	503	506	0.99		0.066 27	0.004 71	0.008 65	0.000 19	65.2		4.5	55.6	1.2
14BM-07-10	1 653	3 035	0.54		0.027 09	0.001 32	0.004 45	0.000 05	27.1		1.3	28.6	0.3
14BM-07-11	2 223	3 809	0.58		0.026 08	0.001 18	0.004 23	0.000 05	26.1		1.2	27.2	0.4
14BM-07-12	235	450	0.52		0.084 93	0.008 26	0.010 41	0.000 32	82.8		7.7	66.7	2.1
14BM-07-13	156	834	0.19		1.064 09	0.032 25	0.109 56	0.001 67	735.8		15.9	670.2	9.7
14BM-07-14	1 436	2 741	0.52		0.038 62	0.003 10	0.004 98	0.000 12	38.5		3.0	32.0	0.8
14BM-07-15	2 077	3 499	0.59		0.035 80	0.001 72	0.004 86	0.000 06	35.7		1.7	31.2	0.4
14BM-07-16	446	543	0.82		0.074 47	0.005 49	0.009 28	0.000 20	72.9		5.2	59.6	1.3
14BM-07-17	1 598	909	1.76		0.063 87	0.004 88	0.008 35	0.000 22	62.9		4.7	53.6	1.4
14BM-07-18	428	581	0.74		0.066 87	0.006 66	0.008 33	0.000 26	65.7		6.3	53.5	1.6
14BM-07-19	5102	4501	1.13		0.036 65	0.001 53	0.004 68	0.000 06	36.5		1.5	30.1	0.4
14BM-07-20	1 662	3 098	0.54		0.034 78	0.001 69	0.005 03	0.000 07	34.7		1.7	32.3	0.5
14BM-07-21	1 510	2 906	0.52		0.037 54	0.002 40	0.004 24	0.000 09	37.4		2.3	27.3	0.6
14BM-07-22	1 915	2 885	0.66		0.034 78	0.002 38	0.004 72	0.000 08	34.7		2.3	30.4	0.5
14BM-07-23	1 116	2 116	0.53		0.065 02	0.003 79	0.009 06	0.000 36	64.0		3.6	58.1	2.3
14BM-07-24	271	434	0.62		0.177 77	0.010 77	0.023 15	0.000 41	166.1		9.3	147.5	2.6
14BM-07-25	658	636	1.04		0.060 40	0.004 88	0.006 57	0.000 22	59.5		4.7	42.2	1.4
14BM-07-26	4 075	4 438	0.92		0.029 45	0.001 46	0.004 39	0.000 05	29.5		1.4	28.2	0.3
14BM-07-27	482	607	0.79		0.065 47	0.005 56	0.008 25	0.000 20	64.4		5.3	53.0	1.3
14BM-07-28	440	533	0.83		0.074 56	0.006 72	0.008 34	0.000 19	73.0		6.4	53.5	1.2
14BM-07-29	1 166	2 170	0.54		0.037 64	0.001 92	0.004 98	0.000 07	37.5		1.9	32.1	0.5
14BM-07-30	1 957	2 784	0.70		0.032 71	0.001 92	0.004 49	0.000 07	32.7		1.9	28.9	0.4
14BM-14-01	268	404	0.66		0.064 09	0.003 94	0.009 43	0.000 19	63.1		3.8	60.5	1.2
14BM-14-02	286	423	0.68		0.074 28	0.004 56	0.009 82	0.000 16	72.8		4.3	63.0	1.0
14BM-14-03	274	428	0.64		0.076 71	0.004 41	0.009 65	0.000 19	75.0		4.2	61.9	1.2
14BM-14-04	454	467	0.97		0.070 16	0.004 29	0.009 56	0.000 16	68.9		4.1	61.3	1.0
14BM-14-05	267	383	0.70		0.058 46	0.003 73	0.009 03	0.000 16	57.7		3.6	57.9	1.0
14BM-14-06	567	748	0.76		0.061 26	0.003 15	0.008 51	0.000 11	60.4		3.0	54.6	0.7
14BM-14-07	293	424	0.69		0.059 87	0.003 76	0.009 09	0.000 18	59.0		3.6	58.3	1.1
14BM-14-08	216	311	0.69		0.092 69	0.005 96	0.009 35	0.000 17	90.0		5.5	60.0	1.1
14BM-14-09	359	479	28.41		0.121 52	0.000 00	0.015 29	0.000 00	116.4		0.0	97.8	0.0
14BM-14-10	217	355	56.82		0.156 56	0.000 00	0.014 56	0.000 00	147.7		0.0	93.2	0.0
14BM-14-11	242	328	0.74		0.070 91	0.005 04	0.009 04	0.000 19	69.6		4.8	58.0	1.2
14BM-14-12	377	479	0.79		0.060 66	0.003 40	0.008 74	0.000 13	59.8		3.3	56.1	0.8
14BM-14-13	348	450	0.77		0.061 01	0.003 39	0.008 68	0.000 15	60.1		3.2	55.7	1.0
14BM-14-14	319	459	0.69		0.066 81	0.004 10	0.008 80	0.000 14	65.7		3.9	56.5	0.9
14BM-14-15	234	349	0.67		0.065 29	0.004 09	0.008 98	0.000 17	64.2		3.9	57.6	1.1
分析点号	含量/10^-6			Th/U	同位素比值					年龄/Ma
分析点号	Th	U		Th/U	²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ		²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ
14BM-19-01	92	139	0.66		0.067 44	0.004 22	0.009 35	0.000 15	66.3		4.0	60.0	1.0
14BM-19-02	210	220	0.95		0.063 74	0.003 04	0.008 89	0.000 13	62.7		2.9	57.1	0.8
14BM-19-03	67	109	0.61		0.079 58	0.005 52	0.009 11	0.000 18	77.8		5.2	58.5	1.2
14BM-19-04	108	128	0.85		0.071 40	0.004 20	0.009 05	0.000 17	70.0		4.0	58.1	1.1
14BM-19-05	105	198	0.53		0.066 40	0.003 73	0.009 31	0.000 15	65.3		3.6	59.7	0.9
14BM-19-06	102	57	1.78		0.066 86	0.004 32	0.008 63	0.000 19	65.7		4.1	55.4	1.2
14BM-19-07	110	144	0.77		0.063 85	0.004 26	0.008 95	0.000 16	62.8		4.1	57.5	1.0
14BM-19-08	136	85	1.61		0.069 15	0.004 89	0.009 21	0.000 19	67.9		4.6	59.1	1.2
14BM-19-09	121	136	0.89		0.069 55	0.004 77	0.009 24	0.000 19	68.3		4.5	59.3	1.2
14BM-19-10	148	95	1.57		0.065 63	0.004 95	0.009 21	0.000 17	64.5		4.7	59.1	1.1
14BM-19-11	142	176	0.81		0.070 16	0.004 08	0.009 14	0.000 15	68.9		3.9	58.6	1.0
14BM-19-12	189	212	0.89		0.062 11	0.003 75	0.008 83	0.000 14	61.2		3.6	56.7	0.9
14BM-19-13	95	110	0.86		0.069 82	0.004 15	0.009 32	0.000 18	68.5		3.9	59.8	1.1
14BM-19-14	132	122	1.09		0.067 44	0.003 69	0.008 56	0.000 16	66.3		3.5	54.9	1.0
14BM-19-15	94	112	0.84		0.062 54	0.003 99	0.008 64	0.000 17	61.6		3.8	55.5	1.1
14BM-19-16	115	145	0.79		0.067 42	0.004 15	0.009 36	0.000 15	66.3		4.0	60.1	1.0
14BM-19-17	34	86	0.40		0.068 86	0.006 05	0.008 78	0.000 19	67.6		5.7	56.4	1.2
14BM-19-18	149	161	0.93		0.064 23	0.003 96	0.008 99	0.000 16	63.2		3.8	57.7	1.0
14BM-19-19	96	123	0.78		0.077 60	0.004 84	0.009 87	0.000 19	75.9		4.6	63.3	1.2
14BM-19-20	697	113	6.19		0.072 36	0.004 80	0.009 67	0.000 16	70.9		4.5	62.1	1.0
14BM-19-21	87	113	0.77		0.082 53	0.005 81	0.009 54	0.000 17	80.5		5.5	61.2	1.1
14BM-19-22	277	204	1.36		0.066 32	0.003 57	0.008 85	0.000 13	65.2		3.4	56.8	0.8
14BM-19-23	440	325	1.35		0.057 05	0.002 99	0.008 53	0.000 11	56.3		2.9	54.8	0.7
14BM-19-24	134	158	0.85		0.068 43	0.004 52	0.009 26	0.000 14	67.2		4.3	59.4	0.9
14BM-19-25	122	146	0.84		0.068 70	0.004 07	0.008 98	0.000 14	67.5		3.9	57.7	0.9

分析点号	含量/10^-6			Th/U	同位素比值					年龄/Ma
分析点号	Th	U		Th/U	²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ		²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ
14BM-07-01	2 079	2 427	0.86		0.062 00	0.003 41	0.008 65	0.000 19	61.1		3.3	55.5	1.2
14BM-07-02	280	422	0.66		0.086 92	0.007 74	0.009 73	0.000 23	84.6		7.2	62.4	1.5
14BM-07-03	427	494	0.86		0.070 90	0.004 46	0.009 04	0.000 17	69.6		4.2	58.0	1.1
14BM-07-04	351	406	0.86		0.059 33	0.004 55	0.007 55	0.000 26	58.5		4.4	48.5	1.6
14BM-07-05	744	551	1.35		0.063 44	0.005 98	0.008 00	0.000 26	62.5		5.7	51.3	1.6
14BM-07-06	238	383	0.62		0.082 43	0.005 94	0.008 95	0.000 18	80.4		5.6	57.4	1.1
14BM-07-07	2 066	5 051	0.41		0.029 61	0.001 15	0.004 87	0.000 06	29.6		1.1	31.3	0.4
14BM-07-08	397	426	0.93		0.064 99	0.004 11	0.008 20	0.000 17	63.9		3.9	52.6	1.1
14BM-07-09	503	506	0.99		0.066 27	0.004 71	0.008 65	0.000 19	65.2		4.5	55.6	1.2
14BM-07-10	1 653	3 035	0.54		0.027 09	0.001 32	0.004 45	0.000 05	27.1		1.3	28.6	0.3
14BM-07-11	2 223	3 809	0.58		0.026 08	0.001 18	0.004 23	0.000 05	26.1		1.2	27.2	0.4
14BM-07-12	235	450	0.52		0.084 93	0.008 26	0.010 41	0.000 32	82.8		7.7	66.7	2.1
14BM-07-13	156	834	0.19		1.064 09	0.032 25	0.109 56	0.001 67	735.8		15.9	670.2	9.7
14BM-07-14	1 436	2 741	0.52		0.038 62	0.003 10	0.004 98	0.000 12	38.5		3.0	32.0	0.8
14BM-07-15	2 077	3 499	0.59		0.035 80	0.001 72	0.004 86	0.000 06	35.7		1.7	31.2	0.4
14BM-07-16	446	543	0.82		0.074 47	0.005 49	0.009 28	0.000 20	72.9		5.2	59.6	1.3
14BM-07-17	1 598	909	1.76		0.063 87	0.004 88	0.008 35	0.000 22	62.9		4.7	53.6	1.4
14BM-07-18	428	581	0.74		0.066 87	0.006 66	0.008 33	0.000 26	65.7		6.3	53.5	1.6
14BM-07-19	5102	4501	1.13		0.036 65	0.001 53	0.004 68	0.000 06	36.5		1.5	30.1	0.4
14BM-07-20	1 662	3 098	0.54		0.034 78	0.001 69	0.005 03	0.000 07	34.7		1.7	32.3	0.5
14BM-07-21	1 510	2 906	0.52		0.037 54	0.002 40	0.004 24	0.000 09	37.4		2.3	27.3	0.6
14BM-07-22	1 915	2 885	0.66		0.034 78	0.002 38	0.004 72	0.000 08	34.7		2.3	30.4	0.5
14BM-07-23	1 116	2 116	0.53		0.065 02	0.003 79	0.009 06	0.000 36	64.0		3.6	58.1	2.3
14BM-07-24	271	434	0.62		0.177 77	0.010 77	0.023 15	0.000 41	166.1		9.3	147.5	2.6
14BM-07-25	658	636	1.04		0.060 40	0.004 88	0.006 57	0.000 22	59.5		4.7	42.2	1.4
14BM-07-26	4 075	4 438	0.92		0.029 45	0.001 46	0.004 39	0.000 05	29.5		1.4	28.2	0.3
14BM-07-27	482	607	0.79		0.065 47	0.005 56	0.008 25	0.000 20	64.4		5.3	53.0	1.3
14BM-07-28	440	533	0.83		0.074 56	0.006 72	0.008 34	0.000 19	73.0		6.4	53.5	1.2
14BM-07-29	1 166	2 170	0.54		0.037 64	0.001 92	0.004 98	0.000 07	37.5		1.9	32.1	0.5
14BM-07-30	1 957	2 784	0.70		0.032 71	0.001 92	0.004 49	0.000 07	32.7		1.9	28.9	0.4
14BM-14-01	268	404	0.66		0.064 09	0.003 94	0.009 43	0.000 19	63.1		3.8	60.5	1.2
14BM-14-02	286	423	0.68		0.074 28	0.004 56	0.009 82	0.000 16	72.8		4.3	63.0	1.0
14BM-14-03	274	428	0.64		0.076 71	0.004 41	0.009 65	0.000 19	75.0		4.2	61.9	1.2
14BM-14-04	454	467	0.97		0.070 16	0.004 29	0.009 56	0.000 16	68.9		4.1	61.3	1.0
14BM-14-05	267	383	0.70		0.058 46	0.003 73	0.009 03	0.000 16	57.7		3.6	57.9	1.0
14BM-14-06	567	748	0.76		0.061 26	0.003 15	0.008 51	0.000 11	60.4		3.0	54.6	0.7
14BM-14-07	293	424	0.69		0.059 87	0.003 76	0.009 09	0.000 18	59.0		3.6	58.3	1.1
14BM-14-08	216	311	0.69		0.092 69	0.005 96	0.009 35	0.000 17	90.0		5.5	60.0	1.1
14BM-14-09	359	479	28.41		0.121 52	0.000 00	0.015 29	0.000 00	116.4		0.0	97.8	0.0
14BM-14-10	217	355	56.82		0.156 56	0.000 00	0.014 56	0.000 00	147.7		0.0	93.2	0.0
14BM-14-11	242	328	0.74		0.070 91	0.005 04	0.009 04	0.000 19	69.6		4.8	58.0	1.2
14BM-14-12	377	479	0.79		0.060 66	0.003 40	0.008 74	0.000 13	59.8		3.3	56.1	0.8
14BM-14-13	348	450	0.77		0.061 01	0.003 39	0.008 68	0.000 15	60.1		3.2	55.7	1.0
14BM-14-14	319	459	0.69		0.066 81	0.004 10	0.008 80	0.000 14	65.7		3.9	56.5	0.9
14BM-14-15	234	349	0.67		0.065 29	0.004 09	0.008 98	0.000 17	64.2		3.9	57.6	1.1
分析点号	含量/10^-6			Th/U	同位素比值					年龄/Ma
分析点号	Th	U		Th/U	²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ		²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ
14BM-19-01	92	139	0.66		0.067 44	0.004 22	0.009 35	0.000 15	66.3		4.0	60.0	1.0
14BM-19-02	210	220	0.95		0.063 74	0.003 04	0.008 89	0.000 13	62.7		2.9	57.1	0.8
14BM-19-03	67	109	0.61		0.079 58	0.005 52	0.009 11	0.000 18	77.8		5.2	58.5	1.2
14BM-19-04	108	128	0.85		0.071 40	0.004 20	0.009 05	0.000 17	70.0		4.0	58.1	1.1
14BM-19-05	105	198	0.53		0.066 40	0.003 73	0.009 31	0.000 15	65.3		3.6	59.7	0.9
14BM-19-06	102	57	1.78		0.066 86	0.004 32	0.008 63	0.000 19	65.7		4.1	55.4	1.2
14BM-19-07	110	144	0.77		0.063 85	0.004 26	0.008 95	0.000 16	62.8		4.1	57.5	1.0
14BM-19-08	136	85	1.61		0.069 15	0.004 89	0.009 21	0.000 19	67.9		4.6	59.1	1.2
14BM-19-09	121	136	0.89		0.069 55	0.004 77	0.009 24	0.000 19	68.3		4.5	59.3	1.2
14BM-19-10	148	95	1.57		0.065 63	0.004 95	0.009 21	0.000 17	64.5		4.7	59.1	1.1
14BM-19-11	142	176	0.81		0.070 16	0.004 08	0.009 14	0.000 15	68.9		3.9	58.6	1.0
14BM-19-12	189	212	0.89		0.062 11	0.003 75	0.008 83	0.000 14	61.2		3.6	56.7	0.9
14BM-19-13	95	110	0.86		0.069 82	0.004 15	0.009 32	0.000 18	68.5		3.9	59.8	1.1
14BM-19-14	132	122	1.09		0.067 44	0.003 69	0.008 56	0.000 16	66.3		3.5	54.9	1.0
14BM-19-15	94	112	0.84		0.062 54	0.003 99	0.008 64	0.000 17	61.6		3.8	55.5	1.1
14BM-19-16	115	145	0.79		0.067 42	0.004 15	0.009 36	0.000 15	66.3		4.0	60.1	1.0
14BM-19-17	34	86	0.40		0.068 86	0.006 05	0.008 78	0.000 19	67.6		5.7	56.4	1.2
14BM-19-18	149	161	0.93		0.064 23	0.003 96	0.008 99	0.000 16	63.2		3.8	57.7	1.0
14BM-19-19	96	123	0.78		0.077 60	0.004 84	0.009 87	0.000 19	75.9		4.6	63.3	1.2
14BM-19-20	697	113	6.19		0.072 36	0.004 80	0.009 67	0.000 16	70.9		4.5	62.1	1.0
14BM-19-21	87	113	0.77		0.082 53	0.005 81	0.009 54	0.000 17	80.5		5.5	61.2	1.1
14BM-19-22	277	204	1.36		0.066 32	0.003 57	0.008 85	0.000 13	65.2		3.4	56.8	0.8
14BM-19-23	440	325	1.35		0.057 05	0.002 99	0.008 53	0.000 11	56.3		2.9	54.8	0.7
14BM-19-24	134	158	0.85		0.068 43	0.004 52	0.009 26	0.000 14	67.2		4.3	59.4	0.9
14BM-19-25	122	146	0.84		0.068 70	0.004 07	0.008 98	0.000 14	67.5		3.9	57.7	0.9

样品编号	SiO₂	Al₂O₃	TFe₂O₃	MgO	CaO	Na₂O	K₂O	MnO	TiO₂	P₂O₅	烧失量	总量	Y
14BM-01	60.92	16.35	4.46	5.42	6.49	3.50	0.90	0.07	0.50	0.19	1.10	99.89	11.67
14BM-04	50.37	20.70	7.82	4.24	9.55	3.97	1.02	0.16	0.80	0.19	1.06	99.89	18.36
14BM-07	52.70	18.49	8.27	5.19	9.01	2.80	0.91	0.14	0.81	0.20	1.37	99.89	16.61
14BM-12	65.23	17.53	3.91	1.32	3.38	5.03	1.58	0.07	0.50	0.22	1.10	99.87	18.4
14BM-13	65.93	16.78	3.93	1.35	3.40	5.05	1.54	0.06	0.51	0.22	1.09	99.86	18.01
14BM-14	64.97	17.80	7.47	1.74	1.54	0.43	2.65	0.07	0.95	0.07	2.21	99.91	30.38
14BM-19	65.11	17.05	3.97	1.55	4.04	3.73	2.94	0.09	0.45	0.16	0.79	99.89	13.45
样品编号	La	Ce	Pr	Nd	Sm	Eu	Gd	Tb	Dy	Ho	Er	Tm	Yb
14BM-01	18.86	26.63	4.64	17.93	3.303	0.911	2.555	0.404	2.171	0.420	1.155	0.171	1.107
14BM-04	14.81	24.03	4.07	17.17	3.905	1.105	3.207	0.568	3.375	0.680	2.134	0.287	1.875
14BM-07	12.79	19.64	3.61	15.36	3.452	1.067	2.913	0.524	3.134	0.623	1.721	0.271	1.762
14BM-12	20.53	32.91	5.87	23.97	4.879	1.049	3.711	0.626	3.470	0.677	1.924	0.294	1.861
14BM-13	21.06	33.4	5.98	24.18	4.917	1.015	3.71	0.607	3.380	0.655	1.923	0.280	1.796
14BM-14	18.91	31.07	5.52	23.25	5.297	1.197	4.588	0.897	5.754	1.203	3.560	0.584	3.897
14BM-19	18.18	26.14	4.29	16.69	3.339	0.963	2.59	0.428	2.463	0.480	9.129	0.207	1.387
样品编号	Lu	Li	Be	Sc	V	Cr	Co	Ni	Cu	Zn	Ga	Rb	Sr
14BM-01	0.176	9.345	0.873	8.68	83.69	229.30	35.38	145.90	46.22	57.12	15.85	17.46	583.2
14BM-04	0.281	19.52	0.962	16.69	198.00	11.13	22.55	12.01	39.73	113.90	19.74	18.68	650.3
14BM-07	0.281	23.32	0.579	16.85	194.50	12.88	31.54	17.34	18.03	91.98	17.36	18.86	572.4
14BM-12	0.294	17.54	1.443	6.93	51.29	5.80	4.73	3.31	47.05	88.42	18.35	40.46	539.2
14BM-13	0.271	17.11	1.417	6.63	51.22	6.16	4.67	3.12	43.00	86.47	18.28	39.51	537.7
14BM-14	0.638	9.884	1.005	16.03	98.76	13.78	14.86	8.21	31.75	85.28	17.98	62.57	189.5
14BM-19	0.223	16.56	1.036	6.80	58.48	5.59	6.95	2.90	21.17	49.74	16.64	59.12	495.8
样品编号	Zr	Nb	Cs	Ba	Hf	Ta	Pb	Bi	Th	U	δEu	A/CNK	(La/Yb)_N
14BM-01	112.10	4.497	4.214	83.01	3.330	1.711	14.30	0.079	3.323	1.304	0.92	0.88	33.73
14BM-04	27.14	3.529	5.808	327.4	1.137	0.581	30.65	0.676	3.346	0.878	0.93	0.83	8.11
14BM-07	94.92	3.026	19.900	192.2	2.936	0.259	19.05	0.060	2.208	0.601	1.00	0.84	42.99
14BM-12	93.02	8.147	8.362	572.4	3.428	0.608	23.37	0.583	5.066	1.529	0.73	1.09	18.36
14BM-13	72.19	8.106	8.148	476.8	2.812	0.594	22.16	0.542	4.932	1.432	0.70	1.04	14.64
14BM-14	163.20	6.369	5.393	342.7	5.077	0.562	10.37	0.190	4.320	1.066	0.73	2.79	37.78
14BM-19	39.33	5.826	12.400	341.2	1.722	1.729	12.27	0.319	7.681	1.755	0.97	1.02	5.12

样品编号	SiO₂	Al₂O₃	TFe₂O₃	MgO	CaO	Na₂O	K₂O	MnO	TiO₂	P₂O₅	烧失量	总量	Y
14BM-01	60.92	16.35	4.46	5.42	6.49	3.50	0.90	0.07	0.50	0.19	1.10	99.89	11.67
14BM-04	50.37	20.70	7.82	4.24	9.55	3.97	1.02	0.16	0.80	0.19	1.06	99.89	18.36
14BM-07	52.70	18.49	8.27	5.19	9.01	2.80	0.91	0.14	0.81	0.20	1.37	99.89	16.61
14BM-12	65.23	17.53	3.91	1.32	3.38	5.03	1.58	0.07	0.50	0.22	1.10	99.87	18.4
14BM-13	65.93	16.78	3.93	1.35	3.40	5.05	1.54	0.06	0.51	0.22	1.09	99.86	18.01
14BM-14	64.97	17.80	7.47	1.74	1.54	0.43	2.65	0.07	0.95	0.07	2.21	99.91	30.38
14BM-19	65.11	17.05	3.97	1.55	4.04	3.73	2.94	0.09	0.45	0.16	0.79	99.89	13.45
样品编号	La	Ce	Pr	Nd	Sm	Eu	Gd	Tb	Dy	Ho	Er	Tm	Yb
14BM-01	18.86	26.63	4.64	17.93	3.303	0.911	2.555	0.404	2.171	0.420	1.155	0.171	1.107
14BM-04	14.81	24.03	4.07	17.17	3.905	1.105	3.207	0.568	3.375	0.680	2.134	0.287	1.875
14BM-07	12.79	19.64	3.61	15.36	3.452	1.067	2.913	0.524	3.134	0.623	1.721	0.271	1.762
14BM-12	20.53	32.91	5.87	23.97	4.879	1.049	3.711	0.626	3.470	0.677	1.924	0.294	1.861
14BM-13	21.06	33.4	5.98	24.18	4.917	1.015	3.71	0.607	3.380	0.655	1.923	0.280	1.796
14BM-14	18.91	31.07	5.52	23.25	5.297	1.197	4.588	0.897	5.754	1.203	3.560	0.584	3.897
14BM-19	18.18	26.14	4.29	16.69	3.339	0.963	2.59	0.428	2.463	0.480	9.129	0.207	1.387
样品编号	Lu	Li	Be	Sc	V	Cr	Co	Ni	Cu	Zn	Ga	Rb	Sr
14BM-01	0.176	9.345	0.873	8.68	83.69	229.30	35.38	145.90	46.22	57.12	15.85	17.46	583.2
14BM-04	0.281	19.52	0.962	16.69	198.00	11.13	22.55	12.01	39.73	113.90	19.74	18.68	650.3
14BM-07	0.281	23.32	0.579	16.85	194.50	12.88	31.54	17.34	18.03	91.98	17.36	18.86	572.4
14BM-12	0.294	17.54	1.443	6.93	51.29	5.80	4.73	3.31	47.05	88.42	18.35	40.46	539.2
14BM-13	0.271	17.11	1.417	6.63	51.22	6.16	4.67	3.12	43.00	86.47	18.28	39.51	537.7
14BM-14	0.638	9.884	1.005	16.03	98.76	13.78	14.86	8.21	31.75	85.28	17.98	62.57	189.5
14BM-19	0.223	16.56	1.036	6.80	58.48	5.59	6.95	2.90	21.17	49.74	16.64	59.12	495.8
样品编号	Zr	Nb	Cs	Ba	Hf	Ta	Pb	Bi	Th	U	δEu	A/CNK	(La/Yb)_N
14BM-01	112.10	4.497	4.214	83.01	3.330	1.711	14.30	0.079	3.323	1.304	0.92	0.88	33.73
14BM-04	27.14	3.529	5.808	327.4	1.137	0.581	30.65	0.676	3.346	0.878	0.93	0.83	8.11
14BM-07	94.92	3.026	19.900	192.2	2.936	0.259	19.05	0.060	2.208	0.601	1.00	0.84	42.99
14BM-12	93.02	8.147	8.362	572.4	3.428	0.608	23.37	0.583	5.066	1.529	0.73	1.09	18.36
14BM-13	72.19	8.106	8.148	476.8	2.812	0.594	22.16	0.542	4.932	1.432	0.70	1.04	14.64
14BM-14	163.20	6.369	5.393	342.7	5.077	0.562	10.37	0.190	4.320	1.066	0.73	2.79	37.78
14BM-19	39.33	5.826	12.400	341.2	1.722	1.729	12.27	0.319	7.681	1.755	0.97	1.02	5.12