Cambrian Qimantagh island arc in the East Kunlun orogen: Evidences from zircon U-Pb ages, lithogeochemistry and Hf isotopes of high-Mg andesite/diorite from the Lalinggaolihe area

doi:10.13745/j.esf.sf.2020.11.30

Abstract

Abstract:

The Qimantagh belt is an important component of the East Kunlun orogen and plays a key role in reconstructing the early Paleozoic convergent history of the northern Tibetan Plateau. The Qimantagh belt used to be interpreted as part of early Paleozoci arc or back-arc basin, however, the geological records of the early-stage of subduction have seldom been reported and the age of subduction initiation still remains poorly constrained. In this paper, we studied the petrology, geochemistry, zircon U-Pb ages and Hf isotopes of volcanic rocks and diorite from the Qimantagh Group of the Lalinggaolihe area and discussed their petrogenesis and tectonic significance. Volcanic rocks are dominated by andesites with moderate SiO₂ contents (54.02%-63.99%), low TiO₂(0.19%-0.24%), Al₂O₃(10.67%-12.86%) and P₂O₅(0.03%-0.05%) contents and low FeO^T/MgO ratios (0.80-1.04), high MgO contents (7.86%-11.44%) and Mg^# (63-69). Diorites have moderate SiO₂ contents (53.62%-55.81%), low TiO₂(0.19%-0.25%), Al₂O₃(10.58%-11.52%) and P₂O₅(0.02%-0.04%) contents and low FeO^T/MgO ratios (0.9-1.0) with high MgO contents (9.86%-11.63%) and Mg^# (64-66). The high-Mg andesites and diorites share similar trace-elements compositions and have low Th(0.22-1.23 μg/g), Rb(4.11-16.11 μg/g) and Ba(66.7-166 μg/g) contents, high Cr(286-668 μg/g) and Ni(57-181 μg/g) contents, moderate δEu (0.91-1.47) and low Sr/Y ratios (19.7-36.1). They also have low total REE contents (11.8-27.3 μg/g) and (La/Yb)_N values (1.3-4.3), indicating weak LREE/HREE fractionation. The primitive mantle-normalized trace-element diagram shows positive Sr, Ba and Pb anomalies and negative Ta, Nb and Ti anomalies. The LA-ICP-MS U-Pb zircon ages of high-Mg andesites and dorites are 519 and 520/516 Ma, respectively. Both zircons share similar Hf isotopic compositions with ε_Hf(t) of +10.5 to +15.8. These results indicate that the andesites and diorites from the Lalinggaolihe area originated from partial melting of depleted mantle wedge in island arc setting during the early stage of subduction of the Proto-Tethyan Ocean. This study further demonstrates that the subduction of paleo-ocean basin in the Qimantagh belt predated 520 Ma, which improves the understanding on the early-stage subduction history of the Proto-Tethys Ocean in the East Kunlun orogen.

Key words: high-Mg andesite/diorite, Cambrian, Qimantagh, East Kunlun

CLC Number:

WANG Bingzhang, PAN Tong, REN Haidong, WANG Tao, ZHAO Zhiyi, FENG Jianping, ZHANG Jinming. Cambrian Qimantagh island arc in the East Kunlun orogen: Evidences from zircon U-Pb ages, lithogeochemistry and Hf isotopes of high-Mg andesite/diorite from the Lalinggaolihe area[J]. Earth Science Frontiers, 2021, 28(1): 318-333.

Figures/Tables 15

References 44

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测试点	w_B/10^-6		Th/U	同位素比值及误差								年龄及误差/Ma
测试点	U	Th	Th/U	²⁰⁷Pb/²⁰⁶Pb	1σ	²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ	²⁰⁸Pb/²³²Th	1σ	²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ	²⁰⁷Pb/²⁰⁶Pb	1σ
样品GS3-1
1	679	431	0.63	0.057 64	0.000 79	0.620 80	0.011 25	0.077 75	0.000 72	0.024 92	0.000 63	490	7	483	4	516	30
2	105	40	0.38	0.060 12	0.001 55	0.673 93	0.017 59	0.082 03	0.000 95	0.028 58	0.000 95	523	11	508	6	608	56
3	362	89	0.25	0.058 09	0.000 76	0.685 38	0.009 41	0.085 51	0.000 58	0.026 98	0.000 49	530	6	529	3	533	29
4	202	90	0.45	0.057 91	0.001 00	0.668 52	0.014 11	0.083 78	0.000 98	0.025 58	0.000 62	520	9	519	6	527	38
5	175	50	0.28	0.058 06	0.001 53	0.675 88	0.017 43	0.084 53	0.001 20	0.026 14	0.000 85	524	11	523	7	532	58
6	467	198	0.42	0.058 00	0.001 02	0.676 47	0.013 30	0.084 42	0.001 05	0.026 37	0.000 50	525	8	522	6	530	38
7	163	82	0.51	0.058 48	0.001 15	0.671 38	0.014 55	0.083 24	0.000 89	0.025 07	0.000 69	522	9	516	5	548	43
8	249	116	0.46	0.058 70	0.000 89	0.676 99	0.010 14	0.083 62	0.000 65	0.025 37	0.000 53	525	6	518	4	556	33
9	222	91	0.41	0.058 64	0.001 04	0.672 98	0.012 16	0.083 21	0.000 77	0.025 36	0.000 47	523	7	515	5	554	39
10	117	30	0.25	0.059 16	0.001 38	0.671 80	0.014 77	0.082 99	0.000 73	0.025 06	0.000 85	522	9	514	4	573	51
11	114	36	0.31	0.059 16	0.001 37	0.674 29	0.015 79	0.083 10	0.000 82	0.025 63	0.000 84	523	10	515	5	573	50
12	136	42	0.31	0.059 27	0.002 15	0.673 55	0.022 82	0.082 59	0.001 16	0.024 22	0.001 38	523	14	512	7	577	79
13	475	88	0.19	0.065 93	0.000 79	1.232 79	0.018 71	0.135 43	0.001 45	0.041 78	0.000 79	816	9	819	8	804	25
14	133	79	0.59	0.081 47	0.001 08	2.279 79	0.029 32	0.203 21	0.001 74	0.061 71	0.000 97	1 206	9	1 193	9	1 233	26
15	212	87	0.41	0.085 56	0.001 01	2.508 70	0.043 27	0.211 60	0.001 94	0.065 82	0.001 51	1 275	13	1 237	10	1 328	23
16	135	124	0.92	0.085 16	0.000 97	2.548 69	0.037 48	0.216 32	0.001 79	0.064 94	0.001 08	1 286	11	1 262	9	1 319	22
17	254	166	0.65	0.167 72	0.001 37	10.903 08	0.120 00	0.469 93	0.004 23	0.127 97	0.001 77	2 515	10	2 483	19	2 535	14
18	247	144	0.58	0.169 19	0.001 52	11.462 88	0.133 11	0.489 67	0.004 13	0.136 67	0.001 53	2 562	11	2 569	18	2 550	15
样品GS5-1
1	543	370	0.68	0.057 86	0.000 84	0.677 04	0.012 87	0.084 58	0.001 02	0.025 20	0.000 55	525	8	523	6	524	32
2	301	93	0.31	0.057 30	0.001 40	0.680 71	0.020 71	0.086 18	0.001 57	0.027 25	0.000 79	527	13	533	9	503	54
3	503	307	0.61	0.057 42	0.000 70	0.666 80	0.009 48	0.083 89	0.000 78	0.025 23	0.000 50	519	6	519	5	508	27
4	601	406	0.68	0.057 27	0.000 74	0.675 44	0.010 76	0.085 20	0.000 95	0.025 99	0.000 64	524	7	527	6	502	29
5	233	134	0.57	0.058 86	0.001 02	0.672 62	0.012 06	0.082 80	0.000 78	0.024 44	0.000 78	522	7	513	5	562	38
6	444	250	0.56	0.058 36	0.001 03	0.682 23	0.013 69	0.084 50	0.001 01	0.025 63	0.000 68	528	8	523	6	543	39
7	139	51	0.36	0.058 27	0.001 43	0.671 16	0.016 66	0.083 52	0.000 98	0.026 28	0.001 08	521	10	517	6	540	54
8	667	307	0.46	0.057 84	0.000 82	0.669 81	0.010 54	0.083 87	0.001 03	0.024 57	0.000 90	521	6	519	6	524	31
9	132	45	0.34	0.057 53	0.001 09	0.672 27	0.014 92	0.084 45	0.000 90	0.026 25	0.000 75	522	9	523	5	512	42
10	702	468	0.67	0.057 61	0.000 70	0.670 48	0.009 27	0.084 06	0.000 80	0.025 46	0.000 61	521	6	520	5	515	27
11	274	89	0.33	0.057 26	0.001 14	0.655 31	0.013 28	0.082 94	0.000 79	0.024 93	0.000 99	512	8	514	5	502	44
12	624	396	0.64	0.057 69	0.000 86	0.667 32	0.010 46	0.083 79	0.000 84	0.024 80	0.000 68	519	6	519	5	518	33
13	550	323	0.59	0.058 49	0.000 83	0.677 14	0.010 10	0.083 91	0.000 99	0.025 15	0.000 56	525	6	519	6	548	31

测试点	w_B/10^-6		Th/U	同位素比值及误差								年龄及误差/Ma
测试点	U	Th	Th/U	²⁰⁷Pb/²⁰⁶Pb	1σ	²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ	²⁰⁸Pb/²³²Th	1σ	²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ	²⁰⁷Pb/²⁰⁶Pb	1σ
样品GS3-1
1	679	431	0.63	0.057 64	0.000 79	0.620 80	0.011 25	0.077 75	0.000 72	0.024 92	0.000 63	490	7	483	4	516	30
2	105	40	0.38	0.060 12	0.001 55	0.673 93	0.017 59	0.082 03	0.000 95	0.028 58	0.000 95	523	11	508	6	608	56
3	362	89	0.25	0.058 09	0.000 76	0.685 38	0.009 41	0.085 51	0.000 58	0.026 98	0.000 49	530	6	529	3	533	29
4	202	90	0.45	0.057 91	0.001 00	0.668 52	0.014 11	0.083 78	0.000 98	0.025 58	0.000 62	520	9	519	6	527	38
5	175	50	0.28	0.058 06	0.001 53	0.675 88	0.017 43	0.084 53	0.001 20	0.026 14	0.000 85	524	11	523	7	532	58
6	467	198	0.42	0.058 00	0.001 02	0.676 47	0.013 30	0.084 42	0.001 05	0.026 37	0.000 50	525	8	522	6	530	38
7	163	82	0.51	0.058 48	0.001 15	0.671 38	0.014 55	0.083 24	0.000 89	0.025 07	0.000 69	522	9	516	5	548	43
8	249	116	0.46	0.058 70	0.000 89	0.676 99	0.010 14	0.083 62	0.000 65	0.025 37	0.000 53	525	6	518	4	556	33
9	222	91	0.41	0.058 64	0.001 04	0.672 98	0.012 16	0.083 21	0.000 77	0.025 36	0.000 47	523	7	515	5	554	39
10	117	30	0.25	0.059 16	0.001 38	0.671 80	0.014 77	0.082 99	0.000 73	0.025 06	0.000 85	522	9	514	4	573	51
11	114	36	0.31	0.059 16	0.001 37	0.674 29	0.015 79	0.083 10	0.000 82	0.025 63	0.000 84	523	10	515	5	573	50
12	136	42	0.31	0.059 27	0.002 15	0.673 55	0.022 82	0.082 59	0.001 16	0.024 22	0.001 38	523	14	512	7	577	79
13	475	88	0.19	0.065 93	0.000 79	1.232 79	0.018 71	0.135 43	0.001 45	0.041 78	0.000 79	816	9	819	8	804	25
14	133	79	0.59	0.081 47	0.001 08	2.279 79	0.029 32	0.203 21	0.001 74	0.061 71	0.000 97	1 206	9	1 193	9	1 233	26
15	212	87	0.41	0.085 56	0.001 01	2.508 70	0.043 27	0.211 60	0.001 94	0.065 82	0.001 51	1 275	13	1 237	10	1 328	23
16	135	124	0.92	0.085 16	0.000 97	2.548 69	0.037 48	0.216 32	0.001 79	0.064 94	0.001 08	1 286	11	1 262	9	1 319	22
17	254	166	0.65	0.167 72	0.001 37	10.903 08	0.120 00	0.469 93	0.004 23	0.127 97	0.001 77	2 515	10	2 483	19	2 535	14
18	247	144	0.58	0.169 19	0.001 52	11.462 88	0.133 11	0.489 67	0.004 13	0.136 67	0.001 53	2 562	11	2 569	18	2 550	15
样品GS5-1
1	543	370	0.68	0.057 86	0.000 84	0.677 04	0.012 87	0.084 58	0.001 02	0.025 20	0.000 55	525	8	523	6	524	32
2	301	93	0.31	0.057 30	0.001 40	0.680 71	0.020 71	0.086 18	0.001 57	0.027 25	0.000 79	527	13	533	9	503	54
3	503	307	0.61	0.057 42	0.000 70	0.666 80	0.009 48	0.083 89	0.000 78	0.025 23	0.000 50	519	6	519	5	508	27
4	601	406	0.68	0.057 27	0.000 74	0.675 44	0.010 76	0.085 20	0.000 95	0.025 99	0.000 64	524	7	527	6	502	29
5	233	134	0.57	0.058 86	0.001 02	0.672 62	0.012 06	0.082 80	0.000 78	0.024 44	0.000 78	522	7	513	5	562	38
6	444	250	0.56	0.058 36	0.001 03	0.682 23	0.013 69	0.084 50	0.001 01	0.025 63	0.000 68	528	8	523	6	543	39
7	139	51	0.36	0.058 27	0.001 43	0.671 16	0.016 66	0.083 52	0.000 98	0.026 28	0.001 08	521	10	517	6	540	54
8	667	307	0.46	0.057 84	0.000 82	0.669 81	0.010 54	0.083 87	0.001 03	0.024 57	0.000 90	521	6	519	6	524	31
9	132	45	0.34	0.057 53	0.001 09	0.672 27	0.014 92	0.084 45	0.000 90	0.026 25	0.000 75	522	9	523	5	512	42
10	702	468	0.67	0.057 61	0.000 70	0.670 48	0.009 27	0.084 06	0.000 80	0.025 46	0.000 61	521	6	520	5	515	27
11	274	89	0.33	0.057 26	0.001 14	0.655 31	0.013 28	0.082 94	0.000 79	0.024 93	0.000 99	512	8	514	5	502	44
12	624	396	0.64	0.057 69	0.000 86	0.667 32	0.010 46	0.083 79	0.000 84	0.024 80	0.000 68	519	6	519	5	518	33
13	550	323	0.59	0.058 49	0.000 83	0.677 14	0.010 10	0.083 91	0.000 99	0.025 15	0.000 56	525	6	519	6	548	31

测试点	w_B/10^-6		Th/U	同位素比值及误差								年龄及误差/Ma
测试点	U	Th	Th/U	²⁰⁷Pb/²⁰⁶Pb	1σ	²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ	²⁰⁸Pb/²³²Th	1σ	²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ	²⁰⁷Pb/²⁰⁶Pb	1σ
14	477	288	0.60	0.059 19	0.000 83	0.683 18	0.012 59	0.083 31	0.000 97	0.024 71	0.000 62	529	8	516	6	574	31
15	435	265	0.61	0.057 69	0.000 77	0.662 46	0.010 35	0.083 05	0.000 99	0.024 87	0.000 51	516	6	514	6	518	29
16	356	170	0.48	0.057 70	0.000 72	0.673 32	0.009 62	0.084 37	0.000 82	0.026 92	0.000 44	523	6	522	5	518	27
17	171	70	0.41	0.058 49	0.001 39	0.670 43	0.015 44	0.083 23	0.001 18	0.026 58	0.000 89	521	9	515	7	548	52
18	285	107	0.37	0.059 68	0.000 96	0.685 67	0.012 55	0.083 23	0.001 06	0.027 51	0.000 55	530	8	515	6	592	35
19	159	47	0.30	0.058 30	0.001 67	0.670 37	0.020 40	0.083 42	0.001 14	0.026 01	0.000 75	521	12	517	7	541	63
20	96	26	0.27	0.057 74	0.001 45	0.665 72	0.017 61	0.083 54	0.001 16	0.026 74	0.000 99	518	11	517	7	520	55
21	425	260	0.61	0.058 12	0.000 82	0.670 65	0.011 63	0.083 49	0.001 01	0.025 96	0.000 35	521	7	517	6	534	31
22	406	183	0.45	0.058 60	0.000 74	0.682 96	0.010 45	0.084 25	0.000 84	0.026 96	0.000 41	529	6	521	5	552	28
23	311	127	0.41	0.057 70	0.001 59	0.684 21	0.019 82	0.085 80	0.000 79	0.024 74	0.000 50	529	12	531	5	519	61
样品GLX5-1
1	94	26	0.27	0.057 46	0.001 87	0.633 08	0.021 20	0.080 01	0.001 13	0.029 65	0.001 13	498	13	496	7	509	72
2	191	73	0.38	0.063 50	0.001 32	0.709 84	0.014 62	0.081 22	0.001 27	0.028 59	0.001 01	545	9	503	8	725	44
3	214	80	0.37	0.058 23	0.001 59	0.654 96	0.016 72	0.081 86	0.001 29	0.026 89	0.000 80	512	10	507	8	538	60
4	396	164	0.41	0.057 52	0.000 58	0.651 70	0.010 25	0.081 88	0.000 88	0.026 69	0.000 34	510	6	507	5	512	22
5	143	27	0.19	0.057 88	0.001 33	0.654 40	0.016 20	0.081 92	0.001 01	0.026 87	0.001 24	511	10	508	6	525	51
6	75	21	0.28	0.058 98	0.001 30	0.664 96	0.015 26	0.081 96	0.000 92	0.026 55	0.000 84	518	9	508	6	566	48
7	690	394	0.57	0.058 09	0.000 98	0.656 66	0.013 66	0.081 96	0.001 42	0.028 29	0.000 73	513	8	508	8	533	37
8	69	16	0.23	0.058 90	0.001 81	0.664 73	0.020 86	0.082 54	0.001 47	0.031 08	0.001 48	518	13	511	9	563	67
9	502	252	0.50	0.058 55	0.001 43	0.668 26	0.019 61	0.082 55	0.001 59	0.027 64	0.002 05	520	12	511	9	550	53
10	89	15	0.17	0.057 60	0.001 70	0.655 33	0.019 30	0.083 01	0.001 24	0.026 95	0.001 28	512	12	514	7	514	65
11	591	316	0.53	0.057 88	0.000 65	0.663 34	0.010 56	0.083 04	0.000 96	0.026 91	0.000 28	517	6	514	6	525	25
12	186	55	0.30	0.058 02	0.001 21	0.666 51	0.016 33	0.083 06	0.001 17	0.028 30	0.000 93	519	10	514	7	530	46
13	108	31	0.29	0.058 08	0.001 51	0.661 75	0.015 38	0.083 12	0.001 21	0.030 37	0.001 95	516	9	515	7	533	57
14	537	263	0.49	0.057 23	0.000 61	0.658 57	0.009 23	0.083 28	0.000 80	0.026 83	0.000 31	514	6	516	5	500	23
15	645	465	0.72	0.058 01	0.000 56	0.664 92	0.008 02	0.083 29	0.000 90	0.027 43	0.000 40	518	5	516	5	530	21
16	291	107	0.37	0.057 16	0.001 16	0.659 26	0.012 42	0.083 39	0.001 06	0.026 64	0.000 69	514	8	516	6	498	45
17	64	16	0.26	0.057 79	0.001 33	0.661 51	0.017 08	0.083 47	0.001 22	0.025 08	0.001 43	516	10	517	7	522	50
18	378	136	0.36	0.057 69	0.001 16	0.665 21	0.012 17	0.083 69	0.001 36	0.028 23	0.001 34	518	7	518	8	518	44
19	241	76	0.32	0.058 97	0.000 98	0.682 09	0.010 89	0.083 77	0.000 93	0.026 95	0.000 71	528	7	519	6	566	36
20	279	73	0.26	0.056 90	0.001 20	0.660 22	0.014 89	0.083 95	0.001 25	0.029 20	0.001 26	515	9	520	7	487	47
21	666	475	0.71	0.058 03	0.000 73	0.674 87	0.010 36	0.084 07	0.000 99	0.027 57	0.000 89	524	6	520	6	531	27
22	371	112	0.30	0.057 10	0.000 95	0.674 02	0.012 38	0.085 43	0.001 05	0.027 95	0.001 17	523	8	528	6	495	37
23	106	36	0.34	0.057 43	0.001 46	0.676 11	0.017 68	0.085 63	0.001 04	0.026 69	0.001 70	524	11	530	6	508	56

测试点	w_B/10^-6		Th/U	同位素比值及误差								年龄及误差/Ma
测试点	U	Th	Th/U	²⁰⁷Pb/²⁰⁶Pb	1σ	²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ	²⁰⁸Pb/²³²Th	1σ	²⁰⁷Pb/²³⁵U	1σ	²⁰⁶Pb/²³⁸U	1σ	²⁰⁷Pb/²⁰⁶Pb	1σ
14	477	288	0.60	0.059 19	0.000 83	0.683 18	0.012 59	0.083 31	0.000 97	0.024 71	0.000 62	529	8	516	6	574	31
15	435	265	0.61	0.057 69	0.000 77	0.662 46	0.010 35	0.083 05	0.000 99	0.024 87	0.000 51	516	6	514	6	518	29
16	356	170	0.48	0.057 70	0.000 72	0.673 32	0.009 62	0.084 37	0.000 82	0.026 92	0.000 44	523	6	522	5	518	27
17	171	70	0.41	0.058 49	0.001 39	0.670 43	0.015 44	0.083 23	0.001 18	0.026 58	0.000 89	521	9	515	7	548	52
18	285	107	0.37	0.059 68	0.000 96	0.685 67	0.012 55	0.083 23	0.001 06	0.027 51	0.000 55	530	8	515	6	592	35
19	159	47	0.30	0.058 30	0.001 67	0.670 37	0.020 40	0.083 42	0.001 14	0.026 01	0.000 75	521	12	517	7	541	63
20	96	26	0.27	0.057 74	0.001 45	0.665 72	0.017 61	0.083 54	0.001 16	0.026 74	0.000 99	518	11	517	7	520	55
21	425	260	0.61	0.058 12	0.000 82	0.670 65	0.011 63	0.083 49	0.001 01	0.025 96	0.000 35	521	7	517	6	534	31
22	406	183	0.45	0.058 60	0.000 74	0.682 96	0.010 45	0.084 25	0.000 84	0.026 96	0.000 41	529	6	521	5	552	28
23	311	127	0.41	0.057 70	0.001 59	0.684 21	0.019 82	0.085 80	0.000 79	0.024 74	0.000 50	529	12	531	5	519	61
样品GLX5-1
1	94	26	0.27	0.057 46	0.001 87	0.633 08	0.021 20	0.080 01	0.001 13	0.029 65	0.001 13	498	13	496	7	509	72
2	191	73	0.38	0.063 50	0.001 32	0.709 84	0.014 62	0.081 22	0.001 27	0.028 59	0.001 01	545	9	503	8	725	44
3	214	80	0.37	0.058 23	0.001 59	0.654 96	0.016 72	0.081 86	0.001 29	0.026 89	0.000 80	512	10	507	8	538	60
4	396	164	0.41	0.057 52	0.000 58	0.651 70	0.010 25	0.081 88	0.000 88	0.026 69	0.000 34	510	6	507	5	512	22
5	143	27	0.19	0.057 88	0.001 33	0.654 40	0.016 20	0.081 92	0.001 01	0.026 87	0.001 24	511	10	508	6	525	51
6	75	21	0.28	0.058 98	0.001 30	0.664 96	0.015 26	0.081 96	0.000 92	0.026 55	0.000 84	518	9	508	6	566	48
7	690	394	0.57	0.058 09	0.000 98	0.656 66	0.013 66	0.081 96	0.001 42	0.028 29	0.000 73	513	8	508	8	533	37
8	69	16	0.23	0.058 90	0.001 81	0.664 73	0.020 86	0.082 54	0.001 47	0.031 08	0.001 48	518	13	511	9	563	67
9	502	252	0.50	0.058 55	0.001 43	0.668 26	0.019 61	0.082 55	0.001 59	0.027 64	0.002 05	520	12	511	9	550	53
10	89	15	0.17	0.057 60	0.001 70	0.655 33	0.019 30	0.083 01	0.001 24	0.026 95	0.001 28	512	12	514	7	514	65
11	591	316	0.53	0.057 88	0.000 65	0.663 34	0.010 56	0.083 04	0.000 96	0.026 91	0.000 28	517	6	514	6	525	25
12	186	55	0.30	0.058 02	0.001 21	0.666 51	0.016 33	0.083 06	0.001 17	0.028 30	0.000 93	519	10	514	7	530	46
13	108	31	0.29	0.058 08	0.001 51	0.661 75	0.015 38	0.083 12	0.001 21	0.030 37	0.001 95	516	9	515	7	533	57
14	537	263	0.49	0.057 23	0.000 61	0.658 57	0.009 23	0.083 28	0.000 80	0.026 83	0.000 31	514	6	516	5	500	23
15	645	465	0.72	0.058 01	0.000 56	0.664 92	0.008 02	0.083 29	0.000 90	0.027 43	0.000 40	518	5	516	5	530	21
16	291	107	0.37	0.057 16	0.001 16	0.659 26	0.012 42	0.083 39	0.001 06	0.026 64	0.000 69	514	8	516	6	498	45
17	64	16	0.26	0.057 79	0.001 33	0.661 51	0.017 08	0.083 47	0.001 22	0.025 08	0.001 43	516	10	517	7	522	50
18	378	136	0.36	0.057 69	0.001 16	0.665 21	0.012 17	0.083 69	0.001 36	0.028 23	0.001 34	518	7	518	8	518	44
19	241	76	0.32	0.058 97	0.000 98	0.682 09	0.010 89	0.083 77	0.000 93	0.026 95	0.000 71	528	7	519	6	566	36
20	279	73	0.26	0.056 90	0.001 20	0.660 22	0.014 89	0.083 95	0.001 25	0.029 20	0.001 26	515	9	520	7	487	47
21	666	475	0.71	0.058 03	0.000 73	0.674 87	0.010 36	0.084 07	0.000 99	0.027 57	0.000 89	524	6	520	6	531	27
22	371	112	0.30	0.057 10	0.000 95	0.674 02	0.012 38	0.085 43	0.001 05	0.027 95	0.001 17	523	8	528	6	495	37
23	106	36	0.34	0.057 43	0.001 46	0.676 11	0.017 68	0.085 63	0.001 04	0.026 69	0.001 70	524	11	530	6	508	56

样号	岩性	w_B/%																	Mg^#
样号	岩性	SiO₂			TiO₂			Al₂O₃	TFe₂O₃	MnO	MgO	CaO	Na₂O	K₂O	P₂O₅	Lost	Total	FeO	Mg^#
GS3-1	安山岩	59.29			0.21			10.67	9.15	0.15	11.44	4.09	1.74	0.27	0.03	1.70	99.56		69
GLX2		55.33			0.19			12.86	9.60	0.25	10.74	5.25	3.74	0.19	0.05	1.19	99.39	7.28	67
GLX3		63.99			0.24			12.12	8.20	0.12	7.86	2.62	3.41	0.28	0.04	0.65	99.51	6.64	63
GLX5		54.02			0.19			11.23	11.04	0.20	10.99	6.85	3.58	0.31	0.02	1.35	99.78	7.78	64
GLX5-1	闪长岩	53.62			0.19			10.89	11.63	0.22	11.58	6.99	3.21	0.47	0.04	1.09	99.91	8.23	64
GS5-1		55.07			0.22			11.09	10.55	0.23	10.74	5.95	3.19	0.50	0.02	1.03	99.76		65
GS5-2		55.81			0.25			10.58	10.25	0.23	10.56	6.38	3.10	0.47	0.03	0.98	99.51		65
GS6-1		54.10			0.22			11.36	10.42	0.22	11.28	6.25	3.08	0.56	0.03	1.09	99.78		66
GS6-2		55.03			0.23			11.52	9.86	0.22	10.37	6.39	3.40	0.38	0.03	1.25	99.59		65
样号	岩性	w_B/10^-6
样号	岩性	Sc			Cu			Zn	Rb	Zr	Nb	Hf	Ta	Pb	Th	U	Ba	Cr	Ni
GS3-1	安山岩	29.9			127			71	11.42	29.7	0.88	0.81	0.10	7.79	0.84	0.33	218	614	119
GLX2		35.1			76			69	4.11	61.6	0.79	1.61	0.06	5.32	0.54	0.44	67	668	181
GLX3		26.3			57			64	6.76	72.3	0.97	1.88	0.06	6.91	0.59	0.33	229	268	57
GLX5		47.9			11			78	7.65	23.9	0.72	0.65	0.05	6.87	0.23	0.18	112	580	101
GLX5-1	闪长岩	49.0			10			80	10.70	25.7	0.79	0.67	0.06	5.56	0.22	0.17	122	573	103
GS5-1		42.8			27			86	16.11	23.1	1.07	0.82	0.08	6.51	1.23	0.24	107	615	99
GS5-2		39.5			12			78.3	12.03	23.6	0.98	0.84	0.09	5.56	0.52	0.20	126	616	96
GS6-1		43.9			30			76.5	10.46	23.9	1.12	0.81	0.11	4.50	0.60	0.41	166	616	98
GS6-2		41.5			7			79.5	13.32	23.4	0.95	0.63	0.07	6.82	0.54	0.20	138	528	86
样号	岩性	w_B/10^-6
样号	岩性	Co			Sr			V	La	Ce	Pr	Nd	Sm	Eu	Gd	Tb	Dy	Ho	Er
GS3-1	安山岩	43.3			93			171	2.03	4.46	0.63	2.62	0.72	0.32	0.86	0.16	0.91	0.19	0.52
GLX2		40.6			185			209	3.69	9.47	1.27	5.52	1.41	0.41	1.30	0.20	1.18	0.23	0.74
GLX3		27.8			143			152	4.39	9.40	1.24	5.38	1.38	0.66	1.35	0.23	1.29	0.25	0.74
GLX5		46.7			189			185	1.20	3.22	0.47	2.17	0.77	0.28	0.89	0.14	0.97	0.20	0.62
GLX5-1	闪长岩	49.6			173			185	1.31	3.33	0.48	2.31	0.75	0.30	0.85	0.16	0.96	0.21	0.65
GS5-1		52.6			167			187	1.64	3.90	0.57	2.58	0.79	0.29	0.92	0.16	1.05	0.22	0.60
GS5-2		48.0			177			188	1.70	3.91	0.56	2.53	0.77	0.27	0.93	0.16	0.98	0.20	0.57
GS6-1		47.9			138			180	2.23	4.95	0.70	3.05	0.93	0.33	1.05	0.17	1.08	0.23	0.63
GS6-2		46.4			198			182	2.16	4.33	0.69	3.09	0.89	0.31	0.97	0.17	1.02	0.22	0.60
样号	岩性	w_B/10^-6									(La/ Yb)_N	Y/Yb	δEu	Sr/Y	Nb/Ta	La/Sm	Th/Yb	La/Nb	U/Th
样号	岩性	Tm	Yb	Lu		Y	∑REE				(La/ Yb)_N	Y/Yb	δEu	Sr/Y	Nb/Ta	La/Sm	Th/Yb	La/Nb	U/Th
GS3-1	安山岩	0.08			0.52			0.09	4.41	14.1	2.8	8.42	1.23	21.1	9.18	2.81	0.19	2.30	0.39
GLX2		0.11			0.76			0.12	7.09	26.4	3.5	9.37	0.91	26.0	13.89	2.62	0.08	4.67	0.80
GLX3		0.11			0.74			0.12	7.26	27.3	4.3	9.84	1.47	19.7	15.67	3.19	0.08	4.51	0.55
GLX5		0.09			0.66			0.11	5.45	11.8	1.3	8.22	1.01	34.6	14.89	1.56	0.04	1.66	0.80
GLX5-1	闪长岩	0.09			0.69			0.11	5.77	12.2	1.4	8.30	1.15	30.0	14.17	1.74	0.04	1.65	0.75
GS5-1		0.09			0.61			0.09	5.48	13.5	1.9	9.06	1.02	30.5	12.66	2.08	0.22	1.53	0.19
GS5-2		0.09			0.54			0.09	5.04	13.3	2.3	9.35	0.99	35.2	10.57	2.23	0.10	1.73	0.38
GS6-1		0.09			0.61			0.10	6.35	16.2	2.6	10.40	1.02	21.7	10.20	2.39	0.09	2.00	0.69
GS6-2		0.09			0.60			0.09	5.49	15.2	2.6	9.11	1.00	36.1	14.33	2.45	0.10	2.28	0.36